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  • Springer  (74,709)
  • Wiley-Blackwell  (16,157)
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  • 2005-2009
  • 1980-1984  (53,265)
  • 1955-1959  (36,397)
  • 1925-1929  (6,205)
  • 1980  (53,265)
  • 1959  (19,080)
  • 1958  (17,317)
  • 1925  (6,205)
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  • 2005-2009
  • 1980-1984  (53,265)
  • 1955-1959  (36,397)
  • 1925-1929  (6,205)
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  • 1
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    Bulletin of mathematical biology 20 (1958), S. 71-93 
    ISSN: 1522-9602
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Mathematics
    Notes: Abstract A somewhat different approach to the principle of biotopological mapping, discussed in previous publications, is given. The organism is considered as a set of properties, each of which is in its turn a set of numerous subproperties which are logically included in the corresponding properties. Topology is introduced by an appropriate definition of neighborhoods, and four postulates are stated which concern the mapping of the spaces corresponding to higher organisms on those of lower ones. A number of conclusions are drawn from the postulates. Some of them correspond to well-known facts. For example, in man and some higher organisms appropriate emotional stimuli should produce gastrointestinal or cardiovascular disturbances; or some microorganisms should produce substances harmful to other microorganisms (antibiotics). Some other conclusions are still awaiting verification. One of them is, for example, that there must exist unicellular organisms which produce antibodies to appropriate antigens.
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  • 2
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    Bulletin of mathematical biology 20 (1958), S. 25-32 
    ISSN: 1522-9602
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    Topics: Biology , Mathematics
    Notes: Zusammenfassung Für die Praxis der Pflanzenernährung ist es wichtig, zu wissen, in welcher Weise die Ertragsbildung von der Konzentration eines mineralischen Nährstoffes in der Umgebung der Pflanze abhängt. Da nur diejenigen Nährstoffmengen das physiologische Geschehen in der Pflanze unmittelbar zu beeinflussen vermögen, die sich in der Pflanze befinden, wird angenommen, dass das Wachstum zum Zeitpunktt, d.h. die Geschwindigkeit der Trockensubstanzzunahme zu diesem Zeitpunkt, eine Funktion der zur Zeitt in der Pflanze enthaltenen Nährstoffmenge ist. Diese Nährstoffmenge wird natürlich im Intervall vor dem Zeitpunktt aufgenommen. Deshalb und auch noch aus anderen Gründen hängt das Wachstum zur Zeitt davon ab, wie die in der Umgebung der Pflanze herrschende Konzentration des betrachteten Nährstoffes in demjenigen Zeitintervall verläuft, das sich von der Aussaat bis zum Zeitpunktt erstreckt. Die angegebene Annahme fürhrt zusammen mit einigen weiteren naheliegenden Annahmen zu einem Ansatz, der Ergebnisse liefert, die in verschiedener Hinsicht gut mit der Erfahrung übereinstimmen. Jedoch gibt es auch noch Widersprüche zwischen Theorie und Erfahrung. Durch weitere Ausgestaltung der Theorie lassen sich diese Widersprüche beseitigen. Es wird angeregt, Versuche durchzuführen, deren Resultate Hinweise für die weitere Ausgestaltung der Theorie liefern.
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  • 3
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    Bulletin of mathematical biology 20 (1958), S. 33-70 
    ISSN: 1522-9602
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    Topics: Biology , Mathematics
    Notes: Abstract The dynamics of cell multiplication and differentiation in tissues in asteady state and the kinetics of isotope incorporation into the DNA have been theoretically analyzed. Equations have been derived, with the aid of which thegeneration time, thelife span, and the distribution or rate of death of the cells can be obtained if the tissue is in asteady state, i.e., if the number of cells is maintained constant by constant, equal rates of cell division and cell death and if the mean DNA content per cell is also constant. An equation has also been derived which gives thegeneration time in the case of logarithmic multiplication of cells. Two special cases have been analyzed: InCase 1, the isotope is considered as being introduced into the metabolic system at zero time only; inCase 2, the specific activity of the DNA precursor is considered as being maintained constant. The use of the method has been illustrated by an example in which thegeneration time and themean, themedian, and themode life span, as well as the curve of the rate of death of leukocytes in a patient with chronic leukemic granulocytic leukemia, have been obtained from the rate of P32 incorporation into the DNA. The merits and the limitations of the method are discussed.
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  • 4
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    Bulletin of mathematical biology 20 (1958), S. 95-95 
    ISSN: 1522-9602
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  • 5
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    Bulletin of mathematical biology 21 (1959), S. 1-11 
    ISSN: 1522-9602
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    Topics: Biology , Mathematics
    Notes: Abstract By means of the Laplace transform, the behavior of a simplified model of the cardiovascular system is mathematically formulated. This formulation allows mathematical expression of the periodicity of the cardiac output and the systemic response. With the cardiac output represented as half of a sine function cycle, the systolic aortic pressure becomes the sum of a sine term and exponential terms, while the sum of the exponential terms alone represents the diastolic pressure. The characteristics of the mathematical expressions for systole and diastole are analyzed, and some relationships of potentially practical value are derived. Variation in the parameters of the system yields mathematical results consistent with the expected physical ones.
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    Bulletin of mathematical biology 21 (1959), S. 19-32 
    ISSN: 1522-9602
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    Notes: Abstract A generalization of Landahl's approximation method (H. D. Landahl,Bull. Math. Biophysics,15, 49–61, 1953) for non-linear diffusion problems is suggested. The method is applied to sorption, desorption, and free diffusion problems involving concentration-dependent diffusion coefficients. With some limitations, the results compare favorably with those obtained by numerical methods.
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  • 7
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    Bulletin of mathematical biology 21 (1959), S. 33-60 
    ISSN: 1522-9602
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    Notes: Abstract Recently a theorem for representing current generators in a volume conductor by the superposition of a central dipole, quadrupole, octopole, etc., has been established by G. C. K. Yeh, J. Martinek, and H. de Beaumont (Bull. Math. Biophysics,20, 203–16, 1958). This theorem makes possible the representation of any discrete or line, surface- or volume-distributed current source by a unique model which can be determined for each given case by surface potential measurements and closed form analysis. In this paper the multipole representations of an eccentric dipole and an eccentric double-layer are obtained in terms of the various parameters of the assumed singularities, and the contributions to surface potentials due to each of the multipoles are compared. Certain numerical results corresponding to those of E. Frank (Amer. Heart J.,46, 364–78, 1953) are carried out and compared. Furthermore, the multipole representation of a partially damaged double-layer is also determined and compared with that of an undamaged one. It is concluded that within the range of parameters corresponding to human subjects the higher-order multipoles can contribute significantly to the surface potentials compared with the dipole.
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    Bulletin of mathematical biology 21 (1959), S. 97-100 
    ISSN: 1522-9602
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    Topics: Biology , Mathematics
    Notes: Abstract In line with a recent suggestion by the author (Bull. Math. Biophysics,20, 267–73, September, 1958) that not only does the organism as a whole map on the primordial, but that each organ can also be thus mapped, it is shown that the previously introduced abstract spaces, which represent an organism, contain subspaces which map continuously on the space of the primordial. Several theorems about those subspaces are proven.
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  • 9
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    Bulletin of mathematical biology 21 (1959), S. 71-95 
    ISSN: 1522-9602
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    Notes: Abstract The DNA-protein coding problem is given a general algebraic formulation, the consequences of which are then explored by standard mathematical methods. To keep the treatment self-contained, the mathematical techniques to be used are explained in detail. It is demonstrated that there exista priori a countably infinite number of different abstract DNA-protein codes, thereby showing that inductive attempts to construct such a code will most likely be fruitless. A notion of ergodicity is then introduced, which imposes a number of restrictions on the admissible codes, and, in fact, these considerations enable us toderive a small portion of a code which, if our hypothesis of ergodicity is correct, must occur in nature. Finally, we discuss briefly the problem as to whether there can exist more than one DNA-protein code in nature.
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  • 10
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    Notes: Abstract The present-day practices of electrocardiography and vectorardiography are based upon the theory that the surface potential differences can be assumed to be due to a single dipole inside the body. It is shown in this paper that a dipole cannot account for all the surface potentials due to realistic current generators, and hence the determination of the current generator from surface potential measurements based upon such a theory will lead to inconsistent representations of the heart for one and the same subject. To demonstrate this point two eccentric dipoles of different strengths and locations representing two muscle fibers are taken to be the current generator in a homogeneous spherical conductor. The exact surface potentials are then expressed by means of the “interior sphere theorem” of the authors. With these expressions the magnitude, direction, and location of the resultant dipole are determined by the method of D. Gabor and C. V. Nelson (J. App. Physics,25, 413–16, 1954). The surface potentials due to this resultant dipole are again exactly expressed by means of the “interior sphere theorem” and compared with those due to the eccentric dipoles assumed. It can be seen that the differences can be considerable. It is suggested that the multipole model of the authors (Bull. Math. Biophysics,20, 203–16, 1958) be used as a more accurate and the only unique representation of the heart.
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  • 11
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    Bulletin of mathematical biology 21 (1959), S. 101-106 
    ISSN: 1522-9602
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    Topics: Biology , Mathematics
    Notes: Abstract In a preceding paper (Bull. Math. Biophysics 20, 71–93, 1958) the principle of biotopological mapping was formulated in terms of a continuous mapping of an abstract space, made from the set of biological properties which characterize the organism, by an appropriate definition of neighborhoods. In this paper it is shown that we may consider directly the mappings of the different sets of properties which characterize different organisms without taking recourse to abstract spaces. All the verificable conclusions made in the preceding paper remain valid. A serious difficulty mentioned previously is, however, avoided and the possibility of more general predictions is established.
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  • 12
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    Bulletin of mathematical biology 21 (1959), S. 107-107 
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    Bulletin of mathematical biology 21 (1959), S. 109-128 
    ISSN: 1522-9602
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    Notes: Abstract The general Theory of Categories is applied to the study of the (M, R)-systems previously defined. A set of axioms is provided which characterize “abstract (M, R)-systems”, defined in terms of the Theory of Categories. It is shown that the replication of the repair components of these systems may be accounted for in a natural way within this framework, thereby obviating the need for anad hoc postulation of a replication mechanism. A time-lag structure is introduced into these abstract (M, R)-systems. In order to apply this structure to a discussion of the “morphology” of these systems, it is necessary to make certain assumptions which relate the morphology to the time lags. By so doing, a system of abstract biology is in effect constructed. In particular, a formulation of a general Principle of Optimal Design is proposed for these systems. It is shown under what conditions the repair mechanism of the system will be localized into a spherical region, suggestive of the nuclear arrangements in cells. The possibility of placing an abstract (M, R)-system into optimal form in more than one way is then investigated, and a necessary and sufficient condition for this occurrence is obtained. Some further implications of the above assumptions are then discussed.
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  • 14
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    Bulletin of mathematical biology 21 (1959), S. 141-151 
    ISSN: 1522-9602
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    Topics: Biology , Mathematics
    Notes: Abstract The transient stage of the random dispersal of logistic populations is investigated, using a Sturm-Liouville series leading to an infinite system of non-linear integral equations. These equations are then solved via a successive approximation scheme. R. A. Fisher's (steady-state) velocity of advance paradox is discussed. An illustrative example is worked to the second order of approximation.
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  • 15
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    Bulletin of mathematical biology 21 (1959), S. 153-159 
    ISSN: 1522-9602
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    Notes: Abstract An approximation method using a sine function is used to solve the second degree growth equation for the case in which an organism may simultaneously become dispersed throughout a uniform region. The resulting expression for a special case is compared with the expression obtained by R. Barakat (1959,Bull. Math. Biophysics,21, 141–51), giving the first two terms, by an iterative, procedure. The agreement is satisfactory.
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    Bulletin of mathematical biology 21 (1959), S. 129-140 
    ISSN: 1522-9602
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    Notes: Abstract Diffusion through a flat pore into a large open region is proportional to the linear dimension of the pore and not to its area. This was first explained by Brown and Escombe (1900) for a circular pore and is here generalized, by means of a dimensional argument, to include any type of regular opening. The problem is further generalized to include diffusion through pores of finite thickness, finite distance apart, and into finite regions. Since this problem cannot be solved exactly, an approximation method is introduced. Reasons for the credibility of the approximation are presented. It is then shown, by means of the approximation method, that the diffusive flow through a pore is equal to the total concentration difference divided by the resistance of the system. The resistance, in turn, is the sum of the resistances of all portions of the system, each of which is calculated. The result is compared with results which have been calculated exactly for limiting cases and found to agree very well. The results are then applied to a standard method of computing pore size in membranes, and it is shown that the correction factor is negligible.
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  • 17
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    Bulletin of mathematical biology 21 (1959), S. 161-183 
    ISSN: 1522-9602
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    Topics: Biology , Mathematics
    Notes: Abstract V. S. Ivlev [Experimental Ecology of Nutrition of Fishes, 1955, Moscow (in Russia)] has shown that the food uptake by fishes during a fixed interval of time is an exponential function of the concentration of food. Ivlev's equation is derived here, and it is shown that it can hold only for non-stationary conditions, such as prevailed in Ivlev's experiments. For a stationary state, the rate of food uptake should tend asymptotically to a limiting value as the concentration increases, but the variation is not exponential. Different other aspects of the problem are investigated, and definite new experimental procedures suggested. The implications of Ivlev's findings on the effect of non-uniformity of food distribution upon the rate of food consumption are studied from a mathematical point of view. The conclusion is reached that whereas a fish does not, in the process of eating, move directly to an individual food particle which it perceives, it does move more or less directly to large aggregates of particles, if the latter are distributed nonuniformly.
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    Bulletin of mathematical biology 21 (1959), S. 185-193 
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    Notes: Abstract Some relational aspects of the property of self-reproduction of biological systems are studied. If in addition to the requirement of the property of self-reproduction we add also the requirement of adaptability of the organism to changing environment, this imposes certain conditions on the topology of the graphs which represent such systems. A further study of the relational properties of such systems seems to offer the possibility of deriving the principle of biological mapping from the requirement of self-reproduction and adaptability. An examination of the problem of the original formation of such self-reproducing systems in connection with the established fact of impossibility of spontaneous generation leads to the conclusion that an organism must inhibit such processes which, in the absence of organisms, would lead to spontaneous generation.
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    Bulletin of mathematical biology 21 (1959), S. 195-216 
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    Notes: Abstract In the human, the antagonistic, extensor-flexor system of the leg is an example of a common type of neurophysiological feedback system. After a brief introduction to the neuroanatomy and physiology of this feedback system, the paper formulates transfer functions from temporal response data available in the literature. A feedback stability analysis, based on the extension of Nyquist's stability criteria to multiple-loop systems and utilizing flow-graph techniques, demonstrates the stable behavior of the system. Expressions are given relating the sensitivity of the system to variations in muscle response and Golgi tendon organ (tension receptor) response. By considering the events taking place at synapses and end-plates during “isometric tension-small knee angle excursion” conditions as stationary stochastic processes, an external “noise” input to the system is given, whose spectrum is derived from the statistics of a shot-process representation of these events. The paper concludes with some correlations between the analytical results and clinical syndromes.
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    Bulletin of mathematical biology 21 (1959), S. 217-255 
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    Notes: Abstract In this continuation of a previous report it is shown how the Volterra population dynamics, which underlies the statistical theory, can be based on a variational principle; how the dynamics can be generalized as regards both the behavior of total populations and migration phenomena; and how many directly observable data, such as amplitudes and frequencies of oscillation of a population, fit into the statistical theory and can test it. Such a test is carried out in some detail using the fox-catch data of Elton, with a clear indication that the theory is capable of comprehending the major statistical properties of population-time curves. A final section sketches an extension of the theory to cover secular variations of external conditions such as temperature of the environment.
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  • 21
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    Bulletin of mathematical biology 42 (1980), S. 131-135 
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    Notes: Abstract The theory of complementary variational principles is used to obtain maximum and minimum principles for diffusion problems with Michaelis-Menten kinetics. In an illustrative calculation we obtain an extremely accurate variational solution in good agreement with the numerical solution of McElwain (1978).
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    Bulletin of mathematical biology 42 (1980), S. 137-141 
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    Bulletin of mathematical biology 42 (1980), S. 181-189 
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    Notes: Abstract Necessary and sufficient conditions for primitivity of a product of two Leslie matrices are given. Such a product could be used in modeling the growth of a population governed alternately by two different sets of fertility and survival parameters.
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    Bulletin of mathematical biology 42 (1980), S. 173-180 
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    Notes: Abstract Zadeh's transfer function method for linear time-variable systems is used to apply frequency-domain analysis to a periodically time-varying elastance model of the left ventricle. Left ventricular pressure computed from the system function of the time-varying elastance and the phasors of aortic flow shows a typical waveform of the measured ventricular pressure.
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    Bulletin of mathematical biology 42 (1980), S. 901-901 
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    Bulletin of mathematical biology 42 (1980), S. 147-160 
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    Notes: Abstract A theory of noise fluctuations is developed which is applicable to systems of any size in which unimolecular or bimolecular reactions are occurring. The main difference between small and large reacting systems is that in the former the probability of finding a particle in a particular state does not obey a Gaussian distribution, but satisfies a distribution which reflects the mechanism of the chemical reaction. This difference is reflected in the main result of the theory: an autocorrelation function that is expressible as a sum of exponentials, the amplitudes of which are explicit functions of the moments of the distribution. Thus, by using small systems, the autocorrelation function,in principle, allows the elucidation of reaction mechanisms. Numerical simulations indicate that for reacting systems having ten or fewer particles, the deviation of the autocorrelation function from a single exponential should be easily detectable, and that estimates of the first four moments of the distribution should be possible. Accurate inference of the distribution, however, will require further mathematical and experimental advances.
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    Bulletin of mathematical biology 42 (1980), S. 161-172 
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    Notes: Abstract The recent mathematical formalization of the concepts of matter and extrinsical energy, which are used for the relational representation of biological systems, is employed in the analysis of the important experimental discoveries of Comorosanet al. related to low energy electromagnetic irradiations on enzyme substrates. By means of the present analysis one of the properties inherent to the experimental phenomena is more precisely exposed, and theoretical developments corresponding to “energetical evolutions” in a biological system (Leguizamón, 1976) may now have an experimental basis. Important limitations are introduced for the validity of the commutativity and associativity of cartesian product of sets, when they represent matter and its linked extrinsical energy. In connection with this last aspect, new important knowledge is obtained for the relational mathematical representation of biological systems.
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    Bulletin of mathematical biology 42 (1980), S. 397-429 
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    Notes: Abstract The structure of solutions to a simple spatially dependent population model involving growth and death is investigated. Two forms of motility of the population are considered: (1) random motion only modeled by a Fickian law, and (2) a directed component of motion (chemotaxis), included in addition to the random motion. Under certain growth conditions a traveling wave of constant speed is approached. This speed can be increased by the addition of the chemotaxis with a corresponding increase in the asymptotic population. Development of initial conditions into a wave is illustrated numerically.
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    Bulletin of mathematical biology 42 (1980), S. 365-396 
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    Notes: Abstract This paper describes mechanisms of intracellular and intercellular adaptation that are due to spatial or temporal factors. The spatial mechanisms support self-regulating pattern formation that is capable of directing self-organization in a large class of systems, including examples of directed intercellular growth, transmitter production, and intracellular conductance changes. A balance between intracellular flows and counterflows causes adaptation. This balance can be shifted by environmental inputs. The decrease in Ca2+-modulated outward K+ conductance in certain molluscan nerve cells is a likely example. Examples wherein Ca2+ acts as a second messenger that shunts receptor sensitivity can also be discussed from this perspective. The systems differ in basic ways from recent diffusion models. Chemical transducers driven by membrane-bound intracellular signals can establish long-range intercellular interactions that compensate for variable intercellular distances and are invariant under developmental size changes; diffusional signals do not. The intracellular adaptational mechanisms are formally analogous to intercellular mechanisms that include cellular properties which are omitted in recent reaction-diffusion models of pattern formation. The cellular models use these properties to compute size-invariant properties despite wide variations in their intercellular signals. Mechanisms of temporal adaptation can be derived from the simplest laws of chemical transduction by using a correspondence principle. These mechanisms lead to such properties of intercellular signals as transient overshoot, antagonistic rebound, and an inverted U in sensitivity as intracellular signals or adaptation levels shift. Such effects are implicated in studies of behavioral, reinforcement, motor control, and cognitive coding.
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    Bulletin of mathematical biology 42 (1980), S. 447-459 
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    Notes: Abstract Large radiation doses to the lung can cause early death from cardiopulmonary insufficiency resulting from radiation pneumonitis and pulmonary fibrosis. A model for early death following inhalation of insoluble radioactive particles is propose. The model is based on three assumptions: (1) early death results from damage to a cluster of cells from a large number of cell clusters at risk, (2) the dose that causes early death depends on how the radiation is delivered in time and (3) the cell clusters at risk to damage are equally sensitive ro radiation. Results from asymptotic theory of extreme values, along with biophysical considerations, suggest that the cumultive distribution function for the absorbed radiation dose to the production of pulmonary injury sufficient to cause early death is best estimated by the third asymptotic distribution without a threshold. This distribution function is identical to the Weibull cumulative distribution function. Data for Beagle dogs after inhaling relatively insoluble forms of alpha- or beta-gamma-emitting particles are shown to support the Weibull model.
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    Bulletin of mathematical biology 42 (1980), S. 461-480 
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    Notes: Abstract Models of the human respiratory tract were developed based on detailed morphometric measurements of a silicone rubber cast of the human tracheobronchial airways. Emphasis was placed on the “Typical Path Lung Model” which used one typical pathway to represent a portion of the lung, such as a lobe, or to represent the whole lung. The models contain geometrical parameters, including airway segment diameters, lengths, branching angles and angles of inclination to gravity, which are needed for estimating inhaled particle deposition. Aerosol depositions for various breathing patterns and particle sizes were calculated using these lung models and the modified Findeisen-Landahl computational scheme. The results agree reasonably well with recent experimental data. Regional deposition, including lobar deposition fractions, are also calculated and compared with results based on the ICRP lung deposition model.
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    Bulletin of mathematical biology 42 (1980), S. 481-488 
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    Notes: Abstract The completely symmetrical system is defined as having identical transfer coefficients between pairs of compartments and the same loss coefficient for each compartment. The eigenvalues and eigenvector are explicitly found along with the inverses of the system matrix and the matrix of eigenvectors. Many properties, special instances of more general theorems, can be seen at once from the explicit analytic solution of the initial value, washout and washin problems. The system serves as a known case for testing estimation procedures, algorithms for solutions of linear systems, eigenvalue-eigenvector and inversion routines and is of considerable tutorial value.
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    Bulletin of mathematical biology 42 (1980), S. 431-446 
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    Notes: Abstract The mathematical structures underlying the theories of organismic sets, (M, R)-systems and molecular sets are shown to be transformed naturally within the theory of categories and functors. Their natural transformations allow the comparison of distinct entities, as well as the modelling of dynamics in “organismic” structures.
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    Bulletin of mathematical biology 42 (1980), S. 489-505 
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    Notes: Abstract To explain the sodium conductance change using Wei's dipole model (Wei, 1969), we may expect that during depolarization the dipole's population difference, ΔN, is first reduced and then returns more slowly to its resting value. This paper shows that the experimental results of gating currents support this idea. Such time course of ΔN, however, is not a usual relaxation process. To account for the unusual behavior of ΔN, we propose two additional assumptions: (1) there exists a special coupling system (probably the intramolecular vibrations) whose coupling strength with the dipoles is much stronger than with the thermal bath (intermolecular vibrations), and (2) there also exist “traps” for the dipole's excitation energy so that this energy is transformed into other energy forms at a rate increasing with the increase of depolarization. Experiments suggest that the traps are proteins located at the inner membrane surface.
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    Bulletin of mathematical biology 42 (1980), S. 507-528 
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    Notes: Abstract Current research into the dynamics of iterative ecological and biological models has lead to a number of theorems concerning the existence of various types of iterative dynamical behavior. In particular, much study has been done on the dynamical behavior of the “simplest dynamical system”f b(x)=bx(1−x), which is just the canonical discrete form of logistic growth equations found in ecology, sociobiology, and population biology. In this paper, we make use of some of the techniques and concepts of topological dynamics to construct a number of generalized conjugacy theorems. These theorems are then used to demonstrate that the mappingf b has a number of conjugacy classes in which the dynamics of the iterates is equivalent to within a change of variables. The concepts of fitness and survival in logistic equations are then shown to be independent, if we follow certain intuitive definitions for these concepts. This conclusion follows from a comparison of the conjugacy classes of the functionf b and the extinction sets off b.
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    Notes: Abstract For chemical reactions not at equilibrium but proceeding in the forward direction in the steady state, a result found by a method first introduced by H. G. Britton (1963, 1965) is generalized to prove that if $${{\vec J} \mathord{\left/ {\vphantom {{\vec J} {\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\leftarrow}$}}{J} }}} \right. \kern-\nulldelimiterspace} {\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\leftarrow}$}}{J} }}$$ is the unidirectional flux ratio, $${{\vec J} \mathord{\left/ {\vphantom {{\vec J} {\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\leftarrow}$}}{J} }}} \right. \kern-\nulldelimiterspace} {\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\leftarrow}$}}{J} }}$$ exp (−ΔG/RT). The conditions under which the equality or inequality applies are discussed. If the unidirectional fluxes are not in the steady state, the unidirectional flux ratio is time invariant in certain specific situations. One such important case is for chemical reaction systems with an ordered sequence of reactions. For systems with more than one pathway, $${{\vec J} \mathord{\left/ {\vphantom {{\vec J} {\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\leftarrow}$}}{J} }}} \right. \kern-\nulldelimiterspace} {\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\leftarrow}$}}{J} }}$$ is not constant except for special cases. These results also apply to diffusional and active transport systems.
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    Bulletin of mathematical biology 42 (1980), S. 599-600 
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    Bulletin of mathematical biology 42 (1980), S. 539-549 
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    Bulletin of mathematical biology 42 (1980), S. 551-597 
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    Notes: Abstract The nonlinear second-order difference equationx n+1=axn(1-xn−1), where 0≦x nX≦1 anda ≧1, is examined from varying points of view, analytical, numerical and geometrical. An analytic expression is obtained for an invariant attracting curveC ∞ (a) in phase space, which becomes the central object of study. This basic curve, which replaces the simple parabolic shape typical of many analogous first-order models, may have a complicated geometrical structure. As the parametera increases,C ∞(a) undergoes transformations characterized by the dynamical descriptions: stable node→stable focus→stable limit cycle →chaotic attractor. Although the limited characterization ofchaos by the appearance of nonperiodic solutions and solutions of arbitrarily large period is relied upon, this appears to be only a simplified approximation of the real behavior of solutions. Trajectories (x n, xn+1),n=0,1,…, are calculated using the related nonlinear planar mapT a(x,y)=(y,ay(1−x)), and regions of persistence and escape are described for characteristic values ofa. The study of persistence, of even more fundamental interest than the associated problems of periodicity and stability, receives special attention. We introduce a geometrical model, similar in many respects to that for the well-known analoguex n+1=axn(1−x n), but having several new and important features. It appears that as the parametera increases in the chaotic regime there are infinitely many intermittent bursts of increase in the probability that any initial point (x 0, x1) will persist in the unit square under successive iterations of the mappingT a, an unexpected property that should be of interest for applications. A discussion of the applicability of these results to population dynamics theory is given, and it is suggested that such equations might find useful application to problems in developmental biology as well.
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    Bulletin of mathematical biology 42 (1980), S. 627-645 
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    Notes: Abstract Based on the principle of minimum power, a mathematical model of the functional state of the oxygen transport system is presented. The optimization model minimizes the power expenditure of the heart, bone marrow, lung and other tissues. The model is used to determine the functional parameters of the oxygen transport system in man under both normal and varying barometric pressures. Theoretical results are compared with experimental data.
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    Bulletin of mathematical biology 42 (1980), S. 601-625 
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    Notes: Abstract A quantitative model of ion binding and molecular interactions in the lipid bilayer membrane is proposed and found to be useful in examining the factors underlying such membrane characteristics as shape, sidedness, stability and vesicle size at various cation concentrations. The lipid membrane behaves as a bilayer couple whose preferential radius of curvature depends on the expansion or contraction of one monolayer relative to the other. It is proposed that molecular packing may be altered by electrostatic repulsion of adjacent like-charged phospholipid headgroups, or by bringing two headgroups closer together by divalent cation crossbridging. The surface concentrations of each type of cation-phospholipid complex can be described by simple binding equilibria and the Gouy-Chapman-Stern formulation for the surface potential in a diffuse double layer. The asymmetric distribution of acidic phospholipids in most biological membranes can account for the differential effects of identical ionic environments on either side of the bilayer. The fraction of vesicle material which tends to have a right-side-out orientation may be approximated by a normal distribution about the mean curvature. The theory generates vesicle sidedness distributions that, when fitted to experimental results from human erythrocyte membranes, provide an alternative method of estimating intrinsic cationphospholipid dissociation constants and other molecular parameters of the bilayer. The results also corroborate earlier suggestions that the Gouy-Chapman theory tends to overestimate free counter-ion concentrations at the surface under large surface potentials.
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    Bulletin of mathematical biology 42 (1980), S. 681-689 
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    Notes: Abstract The “yellow strips” on the cuticle of the Oriental Hornet (Vespa orientalis, Hymenoptera, Vespinae), present photoelectric properties. A mathematical model for the relative changes in resistance as a photoconductive process conforms to the general model for a semiconductor with traps.
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    Bulletin of mathematical biology 42 (1980), S. 701-718 
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    Notes: Abstract Damped nonlinear oscillations in biological and biochemical systems are investigated by the extended Krylov-Bogoliubov-Mitropolskii (KBM) method. A review on the extension made by Popov to the KBM method is given and also further improvements are presented. Applications are made to models of oscillating chemical reactions (Lefever and Nicolis, 1971), FitzHugh (1961) equations, and population dynamics (Gatto and Rinaldi, 1977). Comparison to damped oscillating physical and engineering systems is made.
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    Bulletin of mathematical biology 42 (1980), S. 719-728 
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    Notes: Abstract The conditions that will allow the lumping together of several age classes in the Leslie model are investigated. We show that if the lumping is to be valid for all population distributions, then the parameters of the model must be periodic. Lumping is valid when the population is in equilibrium, but equilibrium should be tested before the model is lumped.
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    Bulletin of mathematical biology 42 (1980), S. 647-679 
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    Notes: Abstract Catastrophe theory is a mathematical theory which, allied with a new and controversial methodology, has claimed wide application, particularly in the biological and the social sciences. These claims have recently been heatedly opposed. This article describes the debate and assesses the merits of the different arguments advanced.
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    Bulletin of mathematical biology 42 (1980), S. 765-795 
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    Notes: Abstract Estimates of capillary tracer permeability calculated using multiple indicator data depend upon the particular model adopted to describe blood tissue exchange. The model proposed by Crone (1963) is appropriate when some of the injected tracer diffuses into the tissue but does not return appreciably to the bloodstream before data collection is terminated. Under these conditions extraction of tracer by the tissue depends on a single dimensionless parameter, αcap, defined as the ratio of capillary permeability surface area to water flow. The effects of finite red cell tracer permeability on the Crone model estimate of capillary permeability are examined in the present study. The results indicate that even when back diffusion from the extravascular space is negligible, significant errors in the Crone model estimate can be expected when capillary permeability is relatively high and the ratio of red cell to capillary permeability is less than unity. However, when an aliquot of blood is equilibrated with tracer prior to injection and the dimensionless capillary permeability is relatively low (i.e. αcap ≦ 0.25 for a haematocrit≦50%), the whole blood Crone model estimate of αcap will be within 10% of the actual value, irrespective of red cell permeability. Red cell-plasma exchange for commonly used tracer-organ combinations should not significantly affect Crone estimates of capillary permeability under normal physiological conditions, but may be important in low flow situations.
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    Bulletin of mathematical biology 42 (1980), S. 807-828 
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    Notes: Abstract Assuming truncated ellipsoidal geometry for the right and left ventricles, a model is developed for the myocardium enabling biventricular mechanical behavior to be studied. Employing pressure-volume data taken from normal dog hearts and from hearts in which the pulmonary artery has been banded over periods of 2–40 weeks, it is shown that: (a) right ventricular wall stresses are higher than left ventricular stresses; (b) right ventricular wall stress increases initially to a maximum after 3–4 weeks followed by a decline to normal and even subnormal levels, attaining a minimum value at 32–33 weeks; (c) left ventricular stresses behave in a similar manner, attaining their maximum and minimum levels after 7–8 weeks and 32–33 weeks respectively. These results suggest that surgical or medical therapy in patients with hypertrophied ventricles might be more appropriate during the period of wall stress reduction.
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    Bulletin of mathematical biology 42 (1980), S. 837-845 
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    Notes: Abstract In this paper we describe a mathematical model of the oscillations of the diaphragm which limits the vitreous body from the anterior segment of the human eye after the lens has been removed in a cataract operation. We study the motion of this diaphragm driven by movements of the eye. Firstly, a mathematical statement of the problem is given and then we solve the problem exactly for a given class of eye movements. From the analysis we deduce that significant oscillations of the membrane are driven by saccades and that it is the angular acceleration of the eye which causes these types of oscillations. A numerical example is given.
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    Bulletin of mathematical biology 42 (1980), S. 871-887 
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    Notes: Abstract The Lotka-Volterra system of prey-predator equations is considered with a special type of continuous time delay. In the case of equal diffusion coefficients Hopf’s bifurcation technique is used to show the existence of travelling wave train solutions for the prey-predator system.
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    Bulletin of mathematical biology 42 (1980), S. 861-870 
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    Notes: Abstract A mathematical model of prothrombin activation is being proposed which includes the feedback mechanism of thrombin and the alteration of factor V by thrombin. This model is in good agreement with experimental data for the dependence of the rate of thrombin formation on the concentrations of factors V and X a . In particular, it correctly predicts the existence and location of a maximum in both of these cases.
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    Bulletin of mathematical biology 42 (1980), S. 847-859 
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    Notes: Abstract A new model of the upper tracheobronchial tree is proposed to account for the three-dimensional nature of the airway system. In addition to the tube length, the tube diameter, and the branching angle, the model includes information on the orientation angle of each tube relative to its parent tube. The orientation angle, defined as the angle between two successive bifurcations, is useful for calculating the gravitational inclination of each tube. The information on orientation angle is further used to construct a binary coding system for identifying individual tubes in the airway tree. The proposed model is asymmetrical, but the same principles can be readily used to construct a symmetrical one.
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    Bulletin of mathematical biology 42 (1980), S. 889-897 
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    Notes: Abstract In any control system for which the number of independent controls is smaller than the number of degrees of freedom to be controlled, our choice of control in any state is restricted to a submanifold of smaller dimension than the tangent space. This simple fact has a number of important consequences for questions of biological import; we consider its implications for adaptation, for senescent phenomena and for the determination of tertiary structures of polypeptides through control of certain average properties. We also formulate the Pontryagin Maximum Principle of Optimal control theory in such a way as to inquire whether specific biodynamic systems can be regarded as optimal with respect to rate of accumulation of particular quantities of the system. We find that if this is possible, the quantity in question must play the role of a clock.
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    Bulletin of mathematical biology 42 (1980), S. 899-900 
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    Bulletin of mathematical biology 20 (1958), S. 1-23 
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    Notes: Abstract To account for some of the more important aspects of drug interaction we shall consider a model which can also account for certain general properties of the action of a single drug. A simple model in which there may be enzymatic detoxification of a drug is studied theoretically. The relation between time for appearance of an effect due to the drug and the size of the dose is found to contain the same parameters as the relation between the effectiveness of paired doses and the interval of time between doses. A similar situation holds when the drug is given at a constant rate. When two drugs are administered together, their effect will depend on the manner of interaction, how much of each drug is given, which is given first, and on the interval of time between each administration. A number of plausible types of interaction is considered theoretically in terms of the model, analytical expressions being given for a number of cases. The interaction may be synergistic or antagonistic. In the former case the potentiation may be more than or less than additive depending on the order of delivery and on the time between injections. Methods for the estimation of the parameters from data are discussed.
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    Bulletin of mathematical biology 21 (1959), S. 13-17 
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    Notes: Abstract This paper extends Leslie's vector and matrix treatment of populations. A simple matrix is given for species in which adult mortality and fertility are independent of age, but in which the juvenile mortality rate differs from the adult. The population vector can be changed into a population matrix. This should allow equations using functions of the size of the population to be developed. Genetic variables such as sex or other polymorphisms can be introduced, and the notation allows different systems of selection or non-random mating to be specified.
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    Bulletin of mathematical biology 42 (1980), S. 1-15 
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    Notes: Abstract A computational model to predict deposition of a wide variety of particulate pollutants in several species of mammals is presented. The model incorporates breathing pattern and detailed anatomical models of the respiratory tract based on extensive morphometric measurements of individual airways. The predicted deposition from this general model is in close agreement with observed deposition of monodisperse aerosols in rats. Particle size and density and respiratory breathing patterns are the critical parameters affecting regional deposition.
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    Bulletin of mathematical biology 42 (1980), S. 17-36 
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    Notes: Abstract A theory of antigen-antibody induced particulate aggregation is developed by investigating the stability of model systems of particles. Conditions for the formation of large aggregates are derived by imposing the requirement that at equilibrium a statistically significant number of redundant bonds would occur in a reduced monomer-dimer model system. A relationship is obtained which predicts the fractional agglutination in the reduced dimer system as a function of the antigen, antibody and particulate concentrations: $$\frac{g}{{2f c_0 (1 - g)^{2^ - } }} = \frac{{s_1 }}{r} + \frac{{s_1 s_2 }}{{2!r^2 }} + ... + \frac{{s_1 s_2 ...s_j }}{{j!r^j }},$$ wherec 0 is the initial concentration of monomer,f is a proximity factor,g is the fractional agglutination,s i is the average rate of formation of theith bond from an (i−1)th bound dimer, andr is the average rate of dissociation of a single antibody-antigen bond.
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    Bulletin of mathematical biology 42 (1980), S. 37-56 
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    Notes: Abstract The roles of the concentrations of the three interacting constituents in the aggregation process (antibodies, antigens and particulates) are analyzed in detail. It is shown that the basic equation derived in Part I is consistent over a broad range of conditions with experimental findings previously reported.
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    Bulletin of mathematical biology 42 (1980), S. 57-78 
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    Notes: Abstract A general mathematical model describing the biochemical interactions of the hormones luteinizing hormone releasing hormone (LHRH), luteinizing hormone (LH) and testosterone (T) in the male is presented. The model structure consists of a negative feedback system of three ordinary differential equations, in which the qualitative behavior is either a stable constant equilibrium solution or oscillatory solutions. A specific realization of the model is used to describe the experimental observations of pulsatile hormone release, its experimental suppression, the onset of puberty, the effects of castration, and several other qualitative and quantitative results. This model is presented as a first step in understanding the physicochemical interactions of the hypothalamic-pituitary-gonadal axis.
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    Bulletin of mathematical biology 42 (1980), S. 79-94 
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    Notes: Abstract Based upon the transition rate equation of dipoles in the membrane, we deal with two important aspects of interaction of nerve signals: (1) conditions for nerve excitation and (2) frequency spectrum analysis of nerve impulse. Interrelations between signal amplitudes and frequencies are formulated in detail. There are several important conclusions which can be drawn from our calculations. First, toexcite the nerve, low frequencies are generally more effective than high frequencies. Second, tosedate the nerve (i.e. to suppress undesired activities), high frequencies would suit better. Third, harmonics produced through interactions of nerve signals are not necessarily weaker than the fundamental frequencies. The great significance of our theory is that it indicates in principle the feasibility to alter or rewrite the information contents of a nerve message in our body by applying stimulations of appropriate strengths and frequencies. Thus, the theory provides a physical basis and hence some understanding for a new branch of medicine—neuro therapy such as Nogier's auriculotherapy, Lamy's phonophoresis, Voll's electroacupuncture and the fast rising TENS (transcutaneous electro-neuro stimulation).
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    Bulletin of mathematical biology 42 (1980), S. 107-117 
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    Notes: Abstract A new physical property, called resonance of the B-type is hypothetically attached to the λ =546 nm irradiated crystalline (small) molecules. In this respect an up or down configuration is assumed for those states obtained through irradiation times that are multiples of 5 sec. With these assumptions, the cellular receptors that may detect these states appear to belong to three classes: the up, down and alternatively mixed up-down. Using the classic formalism of eigenvectors and eigenvalues, a simple spectroscopic type of formula is derived, through which all the possible states of the above characteristic may be obtained.
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    Bulletin of mathematical biology 42 (1980), S. 119-130 
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    Notes: Abstract A model of ecosystems with migration is proposed from the viewpoint of flow. This model explains the following two points: (1) How the density-dependent terms in population dynamics arise as a consequence of migration. (2) How the ecosystem exhibits a hierarchy in energy per unit biomass.
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    Bulletin of mathematical biology 42 (1980), S. 143-145 
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    Bulletin of mathematical biology 42 (1980), S. 95-106 
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    Notes: Abstract For precise boundary conditions of biological relevance, it is proved that the steadily propagating plane-wave solution to the Fisher equation requires the unique (eigenvalue) velocity of advance 2(Df)1/2, whereD is the diffusivity of the mutant species andf is the frequency of selection in favor of the mutant. This rigorous result shows that a so-called “wrong equation”, i.e. one which differs from Fisher's by a term that is seemingly inconsequential for certain initial conditions, cannot be employed readily to obtain approximate solutions to Fisher's, for the two equations will often have qualitatively different manifolds of exact solutions. It is noted that the Fisher equation itself may be inappropriate in certain biological contexts owing to the manifest instability of the lowerconcentration uniform equilibrium state (UES). Depicting the persistence of a mutantdeficient spatial pocket, an exact steady-state solution to the Fisher equation is presented. As an alternative and perhaps more faithful model equation for the propagation of certain species properties through a homogeneous population, we consider a reaction-diffusion equation that features a cubic-polynomial rate expression in the species concentration, with two stable UES and one intermediate unstable UES. This equation admits a remarkably simple exact analytical solution to the steadily propagating plane-wave eigenvalue problem. In the latter solution, the sign of the eigenvelocity is such that the wave propagates to yield the “preferred” stable UES (namely, the one further removed from the unstable intermediate UES) at all spatial points ast→∞. The cubic-polynomial equation also admits an exact steady-state solution for a mutant-deficient or mutant-isolated spatial pocket. Finally, the perpetuating growth of a mutant population from an arbitrary localized initial distribution, a mathematical problem analogous to that for ignition in laminar flame theory, is studied by applying differential inequality analysis, and rigorous sufficient conditions for extinction are derived here.
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    Bulletin of mathematical biology 42 (1980), S. 191-220 
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    Notes: Abstract The binding of mono-, di- and trivalent cations to negatively charged surfaces is studied within the framework of a modified Gouy-Chapman equation. For any given combination of ions of the above valences, the existence and uniqueness of the solution for the surface potential is shown. The treatment provides the surface potential and charge density. For a system containing only monovalent and divalent ions, analytical solutions are given. When trivalent ions are also present, a procedure based on numerical integration is described. The distance dependence of the electrostatic potential for planar surfaces is given. The calculations provide the amount of cations tightly bound and the amount trapped in the double layer region. The competition between cations for binding to surfaces is elucidated.
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    Bulletin of mathematical biology 42 (1980), S. 221-238 
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    Notes: Abstract This paper deals with a model describing the behavior of barium-treatedApalysia neurons. The model is represented by a dynamical system, so-called “complete system”, defined in R4 and depending on a small parameter. The study of this system under zero membrane current conditions was performed with the use of the qualitative theory of singular perturbations. We show that this system has a stable periodic solution of the discontinuous type when the small parameter tends to 0+. A reduced system defined in R3, associated to the complete system was also studied: it corresponds to a constant activation of the inward current. We demonstrate that the corresponding hypothetical cell remains silent under zero current conditions.
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    Notes: Abstract In the study of chemical modification of enzymes and other biologically active proteins, plots of fractional residual activity as a function of number of groups modified per enzyme molecule are often used to establish a correlation between the chemical modification and enzyme inactivation reactions and to determine the stoichiometry of the modification reaction. This paper presents a critical examination of the underlying theoretical framework of such graphs. Whereas these plots are usually presented as linear functions, it is shown here that the general equation describing the relationship between inactivation and modification contains an exponential term; therefore, in the general case, the plot is actually a curve. It is suggested that caution be exercised in the interpretation of such plots and that equations such as those derived in the text be used to fit theoretical curves to the data, in order to maximize the information gained from chemical modification experiments.
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    Bulletin of mathematical biology 42 (1980), S. 257-265 
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    Notes: Abstract This communiction argues that so-called “hermaphroditic” tracer systems, which are neither open nor closed, do not exist physically. The argument is based on the assumption that any observable (possibly nonhomogeneous) macroscopic compartment can be approximated by a compartmentC with a finite number of entry points for the tracer, each associated with an abstract subcompartment ofC. It is shown that the “hermaphroditic” property requires that the mean waiting time be infinite in at least one of the subcompartments, or in a subcompartment elsewhere in the system. A subcompartment with infinite mean waiting time must have some sort of memory, of infinite duration, which knows how long a given particle has been retained, however long that is, and thereby determines its probability of departure. Assuming, as seems likely, that no physical basis exists for such an infinite memory, it follows that “hermaphroditic” systems do not exist.
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    Bulletin of mathematical biology 42 (1980), S. 273-274 
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    Bulletin of mathematical biology 42 (1980), S. 275-275 
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    Bulletin of mathematical biology 42 (1980), S. 277-281 
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    Bulletin of mathematical biology 42 (1980), S. 267-272 
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    Notes: Abstract The implication of state space structure on the existence of a repeatable experimentE designed to determine if a states∈L has propertyP or notP is investigated. It is shown that if a state spaceL is connected, then no experimentE is repeatable. This formalism is used to demonstrate that if a propertyP has an associated set of points inL which is dense with dense complement inL, then there exists no repeatable experimentE which can be used to test whethers has propertyP or notP. Other consequences of this formalization are discussed.
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    Bulletin of mathematical biology 42 (1980), S. 282-282 
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    Bulletin of mathematical biology 42 (1980), S. 283-294 
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    Notes: Abstract It has been shown that the resistance of flow and the wall shear increase with the size of the stenosis but these increases are comparatively small due to non-Newtonian behaviour of the blood indicating the usefulness of its rheological character in the functioning of the diseased arterial circulation.
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    Bulletin of mathematical biology 42 (1980), S. 327-337 
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    Notes: Abstract The modern theory of generalized Hamiltonian systems is used to construct a unified canonical description of the linear Lagrangian biodynamics introduced by Kerner.
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    Bulletin of mathematical biology 42 (1980), S. 305-325 
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    Notes: Abstract The purpose of this paper is to justify an asymptotic method developed for the study of peristaltic transport in a tube of arbitrary cross section. Within the framework of long wave approximation, the three-dimensional nonlinear Navier-Stokes equations are reduced to a sequence of two-dimensional linear boundary value problems of Laplace and biharmonic operators. It is shown that, if a Reynolds number is less than some constant, the solution of the approximate equations is indeed an asymptotic approximation to the exact solution of the problem as the ratio of the maximum radius of the tube to the wave length of the peristaltic motion of the wall tends to zero, and the error estimates are expressed inL 2 norms. Furthermore, under the same condition the exact solution is shown to be unique and stable under arbitrary perturbation of spatially periodic disturbance. Application of the stability condition to peristaltic transport in a tube of circular cross section is given.
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    Bulletin of mathematical biology 42 (1980), S. 295-304 
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    Notes: Abstract A mathematical analysis, including existence and uniqueness, is given for some boundary value problems which model the flow of a fluid-solute mixture in a tube which is placed in an interstitium. The model permits an interchange of fluid and solute across the tube walls.
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    Bulletin of mathematical biology 42 (1980), S. 339-364 
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    Notes: Abstract The vertebrate nervous system has topographic interconnections in many parts, known for example as retinotopy, somatotopy, etc. It is plausible that modifiable synapses play an important role in forming and refining these connections together with the sensory experiences. To elucidate the mechanism of topographic organization, we propose a simple model consisting of two nerve fields connected by modifiable excitatory synapses. The model also includes modifiable inhibitory synapses. The behavior of the model is described by a set of simultaneous non-linear integro-differential equations. By analyzing the equations, we obtain the equilibrium solution of topographic connections. It is also proved that a part of the presynaptic field which is frequently stimulated comes to be mapped on a large area of the postsynaptic field so that it has a good resolution.
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    Bulletin of mathematical biology 42 (1980), S. 691-700 
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    Notes: Abstract The steady-state solution of the equations governing substrate exchange between vascular and extravascular compartments separated by a membrane with finite, symmetrical substrate permeability is presented. Substrate removal from the extravascular compartment by Michaelis-Menten saturation type kinetics with negligible diffusion in the axial and instantaneous diffusion in the transverse directions in both compartments are assumed. It is shown that the solution degenerates into known expressions for special linearized and asymptotic cases. The method of solution is also applied to an extension of the original model incorporating autoregulatory feedback effects upon the process responsible for substrate removal.
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    Bulletin of mathematical biology 42 (1980), S. 729-737 
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    Notes: Abstract Global asymptotic stability and equilibrium coexistence is established in two species Lotka-Volterra-type competition when there are time delays in interspecific interaction terms and the intraspecies competition is stronger than the interspecies competition.
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    Bulletin of mathematical biology 42 (1980), S. 739-746 
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    Notes: Abstract The realized (observed) value of Landau’s dominance hierarchy index is examined. Under a model of constant pairwise dominance probabilities, the observed index is shown to be a strongly consistent estimator of the underlying (true) index. However, a large number of encounters between animals is shown to be required in order to reduce bias and variance to practical levels except when the pairwise dominance probabilities are near one.
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    Bulletin of mathematical biology 42 (1980), S. 747-748 
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    Bulletin of mathematical biology 42 (1980), S. 749-749 
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    Bulletin of mathematical biology 42 (1980), S. 751-763 
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    Notes: Abstract The steady state potassium conductance as a function of measured membrane potential difference (p.d.) ϕ of the squid giant axon is corrected for the effect of accumulation of potassium in the periaxonal space. This correction is made on the assumption that several mathematical models of the axon are valid. These are (i) the McIlroy (1975), McIlroy-Hahn (1978) model of membrane conductanceg i(i=K, Na) which is a detailed model of passive transport of ions across the axonal membrane with the aid of mobile, negatively-charged carriers, (ii) the Adelmanet al. (1973) compartmental model of the periaxonal and external bathing-solution spaces, (iii) the enzymatic theory of nervous conduction due to McIlroy (1970 a, b, c), (iv) the Wien dissociative effect of the axolemmic electric field on the weak membrane buffer proposed by Bass and Moore (1968) as a trigger mechanism in nervous excitation and (v) the model (McIlroy, 1979) of the interfacial double-layer p.d.s. which are assumed to exist at the membrane’s surfaces because of the presence of a fixed surface charge. From the correctedg k (ϕ) curves the values of the double-layer p.d.s. of model (v) are deduced and these are shown to lead to a consistent, physically reasonable solution for the distance (approx. 6.8Å) between the fixed surface charges and for the dissociation constants of these sites in their interactions with the ions of the extra-membrane electrolytes. Assuming that the selectivity coefficint of the potassium conducting system for the squid giant axon is approx. 52 it is deduced that the potassium permeability,P ks , of the periaxonal barrier ≈1.37(±0.5)×10−4 cm sec−1 and the thickness of the periaxonal space ≈451±159Å.
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    Bulletin of mathematical biology 42 (1980), S. 797-805 
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    Notes: Abstract The effects of peripheral layer viscosity on physiological characteristics of blood flow through the artery with mild stenosis have been studied. It has been shown that the resistance to flow and the wall shear decrease as the peripheral layer viscosity decreases.
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    Bulletin of mathematical biology 42 (1980), S. 829-836 
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    Notes: Abstract A study was made of Higgins’ model of glycolysis incorporating molecular diffusion of intermediates, utilizing an earlier conjecture due to Landau. Conditions for the existence of asymptotically stable spatio-temporal periodic solutions are obtained.
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    European journal of wildlife research 26 (1980), S. 1-11 
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary At 3-weekly intervals over a period of 13 months, blood samples were taken from the jugular vein of 8 male and 8 female roe deer kept in research enclosures, so that the total of thyroxin (T4 D), T3 U and ureal nitrogen could be established. Once a week the level of activity of the metatarsal glands was recorded by observation. The thyroid gland hormone levels were not dependent upon sex but were higher in the second and third years than in calves (9–17 months). Seasonal differences were observed in the form of higher proportions of T4 in winter, April/May and July. The index free thyroid gland hormone showed no significant seasonal alterations. There is no obvious daily rhythm. No clear relationship between thyroxin content in the blood and activity of the metatarsal glands was discovered. Two-fold high doses of thyroxin did not stimulate production of pheromon noticeably. The level of urea in the blood is somewhat higher in young roe deer than in adults. The level falls in winter and reaches a maximum in summer after the rut. The urea content of blood is inversely correlated to the concentration of thyroxin — it falls as the thyroxin content of the blood rises.
    Abstract: Resumé Afin de déterminer le taux de Thyroxine totale (T4 D), de T3 U et d'Urée, des prélèvements sanguins ont été exécutés, de trois en trois semaines et pendant une période de 12 mois, au niveau de la veine jugulaire de 8 chevreuils mâles et de 8 chevreuils femelles maintenus en enclos. Chaque semaine, le stade d'activité des glandes métatarsales fut noté. La teneur du sang en hormone thyroîdienne était indépendante du sexe de l'animal et était plus élevée du cours de la 2éme et de la 3éme années que chez les chevrillards (9 à 17 mois). Des variations saisonnières de la teneur en T4 dans le sang se manisfestèrent sous forme de pics en hiver, en avril-mai et en juillet. L'indice de l'hormone libre de la glande thyroîde ne présenta aucune variation saisonnière significative. Un rythme quotidien caractérisé n'existe pas. Une relation claire entre la teneur de Thyroxine dans le sang et l'activité des glandes métatarsales n'est pas apparue. La double injection de doses élevées de Thyroxine n'a pas stimulé sensiblement la production de phéromones. Le taux d'Urée sanguine est plus élevé chez les jeunes chevreuils que chez les sujets adultes; on observe en outre une chute au cours de l'hiver et des pointes au cours de l'été aprés le rut. La corrélation entre les taux d'Urée et la concentration de Thyroxine est négative.
    Notes: Zusammenfassung Von 8 männlichen und 8 weiblichen im Versuchsgehege gehaltenen Rehen wurden in 3wöchigem Abstand über einen Zeitraum von 12 Monaten Blutproben aus der Vena jugularis entnommen und damit das Gesamtthyroxin (T4D), das T3U und der Harnstoffstickstoff bestimmt. Wöchentlich einmal wurde durch Beobachtung der Aktivitätsstatus der Metatarsaldrüsen festgehalten. Der Schilddrüsenhormonspiegel war geschlechtsunabhängig, er war im zweiten und dritten Lebensjahr höher als bei den Kitzen (9–17 Monate). Jahreszeitliche Schwankungen wurden bei T4-Blutspiegeln in Form von erhöhten Werten im Winter, April/Mai und Juli beobachtet. Der Index des freien Schilddrüsenhormons wies keine signifikanten saisonalen Veränderungen auf. Eine deutliche Tagesrhythmik besteht nicht. Ein deutlicher Zusammenhang zwischen Thyroxinblutspiegel und Metatarsaldrüsenaktivität war nicht gegeben. Zweimalige hohe Gaben von Thyroxin regten die Pheromonproduktion nicht merklich an. Der Harnstoffblutspiegel ist bei jungen Rehen etwas höher als bei erwachsenen Rehen, er fällt im Winter ab und weist Spitzenwerte im Sommer nach der Brunft auf. Der Harnstoffblutspiegel korreliert mit der Thyroxinkonzentration invers, er fällt mit steigendem Thyroxinblutspiegel.
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    European journal of wildlife research 26 (1980), S. 11-22 
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary 1. Inquiries made in Lower Austria during two consecutive breeding periods and on two fixed days between (November, January) provided data about disperion pattern and breeding success of the Common Buzzard in different landscapes on a basis of average (1977) and high (1978) density of the Common Vole. 2. During all seasons the local population density is determined by the distribution of woods and open countryside and by the density of the Common Vole. In sparesly wooded areas woods can be densely populated by relatively many breeding-pairs, but their number is limited by the prevailing density of the Common Vole which has an influence on the extent of the Buzzard's individual cruising radius. In woodland habitats the presence of the Common Buzzard depends on the availability of suitably large open areas sufficiently rich in prey. During winter, the snow cover can cause the population to fluctuate, although the influence of the habitat on the local population density continues even during these periods. 3. The siting of eyries affects the difficulty of procuring prey. A poor supply of prey necessitates the eyrie being built near the edge of the woodland. 4. Eyries near the edge of the woodland and eyries in deciduous trees seem to be unfavourable for buzzards breeding early in the year. Microclimatic circumstances could play a role in this. 5. Breeding succes is determined by the efficiency of procuring food and the place of the eyrie with regard to the cruising radius. 6. The population of Common Buzzard which was studied is functioning successfully as regards self-regulation.
    Abstract: Resumé 1. Des enquêtes réalisées en Basse-Autriche au cours de deux périodes successives de couvaison et de deux journées intermédaires (novembre, janvier) ont permis de recueillir des données sur le mode de dispersion et sur les succès de l'élevage chez la Buse variable (Buteo buteo) dans différents sites et lors d'années avec densités moyennes de souris (1977) et fortes densités de souris (1978). 2. En toutes saisons les densités locales sont déterminées par la répartition „forêt-paysage ouvert“ et par l'abondance des souris. Dans des régions à faible taux de boisement la densité des couples nicheurs peut être relativement élevée, leur nombre étant cependant limité par le rayon d'action individuel, lequel est déterminé par l'abondance des souris. Dans les régions forestières, la densité de la Buse dépend de la présence de surfaces dégagées plus étendues et également plus riches en proies. Au cours de la mauvaise saison, l'enneigement peut déterminer des variations d'effectifs mais l'influence de la configuration du paysage sur les densités de population locales ne disparait pas pour autant. 3. La situation des aires de nidification est une question d'efficacité de la prédation. Une efficacité prédatrice moindre amène les oiseaux à installer leurs aires en bordure de la forêt. 4. Des aires installées en bordure de la forêt ou encore dans des feuillus constituent de toute évidence des situations défavorables pour la Buse, dont la période de nidification est précoce. A cet égard, des facteurs de micro-climat pouraient jouer un rôle. 5. Le succès de l'élevage des jeunes est déterminé par l'efficacité de l'approvisionnement alimentaire et par la situation de l'aire en relation avec le rayon d'action. 6. La population des buses étudiée ici se trouve dans une phase d'auto-régulation effective.
    Notes: Zusammenfassung 1. In Niederösterreich durchgeführte Erhebungen in zwei aufeinanderfolgenden Brutperioden und an zwei dazwischenliegenden Stichtagen (November, Januar) haben Unterlagen über Dispersionsmuster und Aufzuchterfolge beim Mäusebussard(Buteo buteo) in verschiedenen Landschaftssituationen bei durchschnittlichen (1977) und hohen (1978) Feldmausdichten erbracht. 2. Zu allen Jahreszeiten sind die lokalen Siedlungsdichten durch die Verteilung von Wald und offener Landschaft und durch das herrschende Feldmausangebot bestimmt. In waldarmen Gebieten können Waldflächen von relativ vielen Brutpaaren besiedelt werden, ihre Zahl ist aber durch die von der herrschenden Feldmausdichte beeinflußte Ausdehnung der individuellen Aktionsräume limitiert. In Waldlandschaften ist das Vorkommen von Mäusebussarden vom Vorhandensein entsprechend großer und ausreichend beutereicher offener Flächen abhängig. Im Winterhalbjahr kann Schneebedeckung Bestandsverschiebungen bedingen, der Einfluß der Landschaftssituation auf die lokalen Siedlungsdichten bleibt aber auch in diesen Perioden erhalten. 3. Die Lage der Horststandorte ist eine Frage der Effizienz der Beutebeschaffung. Geringe Fangeffizienzen erzwingen waldrandnahe Horststandorte. 4. Waldrandnahe Horststandorte und Horste in Laubbäumen sind für den jahreszeitlich früh brütenden Mäusebussard offensichtlich ungünstig. Mikroklimatische Faktoren können dabei eine Rolle spielen. 5. Der Aufzuchterfolg wird durch die Effizienz der Nahrungsbeschaffung und durch die Situation des Horststandortes in bezug zum Aktionsraum bestimmt. 6. Die untersuchte Population des Mäusebussards befindet sich im Stadium einer funktionierenden Selbstregulation.
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    European journal of wildlife research 26 (1980), S. 41-44 
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary A six-years-old asparagus bed was partially cleared of weeds and the development of the yield in the following year was traced. Even the highest level of damage (cutting back 40 cm each week) brought about no loss in comparison with the control (weeds up to 230 cm high). More stems were formed, with a lower individual weight.
    Abstract: Resumé Dans une culture d'asperges âgée de 6 ans, l'effet de l'élimination partielle de la végétation adventice sur l'évolution de la production au cours de l'année suivante a été observé. Même le traitement le plus énergique — recoupe hebdomadaire jusqu'à 40 cm — n'entraîna aucune perte par rapport à la parcelletémoin où la végétation adventice atteignait jusqu'à 2.30 m de hauteur. Un nombre accru de tiges fut obtenu, dont le poids individuel était cependant plus faible.
    Notes: Zusammenfassung In einer sechsjährigen Spargelanlage wurde das Kraut teilweise entfernt und die Ertragsentwicklung im Folgejahr verfolgt. Selbst die stärkste Schädigungsstufe (jede Woche Rückschnitt auf 40 cm) brachte im Vergleich zur Kontrolle (Kraut bis 230 cm hoch) keine Verluste. Es wurden mehr Stangen ausgebildet, die ein geringeres Einzelgewicht hatten.
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    European journal of wildlife research 26 (1980), S. 45-47 
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    Description / Table of Contents: Summary The skull of a one-year-old knobber with a short jaw was compared with a normal skull. Thereby it was found that the bones of the front skull (os lacrimale, os incisivum, os nasale and os maxillare) were much too small. The brain-case had roughly the normal dimensions.
    Abstract: Resumé On compare un crâne brachygnathe d'un brocard d'un an avec un crâne normal: les os de la face — en particulier ceux du larmier, de l'intermaxillaire, du nez et des maxillaires supérieurs — apparaissent sensiblement trop petits. Les os des capsules crâniennes présentaient une conformation nornale.
    Notes: Zusammenfassung Ein Schädel mit Kurzkiefrigkeit eines einjährigen Knopfbockes wird einem Normalschädel gegenübergestellt. Dabei erwiesen sich die Knochen im Gesichtsschädel — vor allem das Tränen-, Zwischenkiefer-, Nasen- und Oberkieferbein — als wesentlich zu klein. Die Knochen der Gehirnkapsel hatten etwa die normalen Größenverhältnisse.
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    European journal of wildlife research 26 (1980), S. 54-60 
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    European journal of wildlife research 26 (1980), S. 61-66 
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary From 1976 to 1979, 150 stomach/intestinal tracts and 250 faeces of raccoon (Procyon lotor [L.]) from North-Hessen and adjoining areas of North-Rhine Westphalia were examined on the basis of their food content. In each case, approximately one third of the food components were vertebrates, invertebrates and plants. Seasonal differences in the prey material can be detected.
    Abstract: Résumé De 1976 à 1979, le contenu alimentaire de 150 tractus digestifs et de 250 échantillons de matière fécale de ratons laveurs (Procyon lotor [L.]) récoltés dans le Nord de la Hesse et dans les régions limitrophes de Rhénanie-Westphalie a été analysé. Les Vértébrés, les Invertébrés et les végétaux se partagent chaque fois approximativement le tiers du contenu stomacal. Des variations saisonnières des quantités de proies sont décelables.
    Notes: Zusammenfassung Von 1976 bis 1979 wurden 150 Magen-Darm-Trakte und 250 Losungen des Waschbären (Procyon lotor [L.]) aus Nordhessen und angrenzenden Teilen von Nordrhein-Westfalen auf ihren Nahrungsinhalt untersucht. Annähernd jeweils ein Drittel der Nahrungsanteile entfallen auf Wirbeltiere, Wirbellose und Pflanzen. Jahreszeitlich bedingte Schwankungen der Beuteanteile sind naclizuweisen.
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    European journal of wildlife research 26 (1980), S. 72-75 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary The author describes a set of elk antlers unearthed in 1928 5 km north-west of Trzemeszno within the boundary of the village of Łukaszewko in Poland. According to the formula of the International Hunting Council for Game Preservation (Conseil International de la Chasse), 478.3 points should be awarded: according to that of the Boone and Crockett Club, 217 2/8 points. The head is compared with the best trophies from European, Asian and American elk.
    Abstract: Résumé Description est donnée d'un bois d'Elan retrouvé lors de fouilles en 1928 à 5 km au Nord-Ouest de Trzemeszno dans le canton du village de Lukazewsko en Pologne. Ce bois ateint, selon la formule du Conseil International de la Chasse, une cote de 478,3 points, et, selon la formule du Boone et Crockett-Club, une cote de 217 points 2/8. Ces bois sont comparés avec les trophées-records des différentes aires de dispersion de l'Elan en Europe, en Asie et en Amérique.
    Notes: Zusammenfassung Beschrieben wird ein 1928 5 km nordwestlich von Trzemeszno in der Gemarkung des Dorfes Łukaszewko in Polen ausgegrabenes Elchgeweih, für das nach der Formel des Internationalen Jagdrates zur Erhaltung des Wildes 478,3 Punkte, nach der Formel des Boone und Crockett Clubs 217 2/8 Punkte errechnet wurden. Verglichen wird das Geweih mit den Spitzentrophäen aus europäischen, asiatischen und amerikanischen Elchvorkommen.
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    European journal of wildlife research 26 (1980), S. 95-97 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary The paper describes a roe buck (Capreolus capreolus L.) with “peruque” antlers of unusual dimensions. The skull with antlers weighed 6,070 gr. in the natural state and 2,020 gr. after drying.
    Abstract: Resumé Description est faite d'un Chevreuil (Capreolus capreolus L.) dont les bois, en perruque, présentent un développement exceptionnel. A l'état naturel, le poids du crâne surmonté des bois en perruque atteint 6070 gr., après séchage, 2020 gr.
    Notes: Zusammenfassung Beschrieben wird ein Rehbock (Capreolus capreolus L.) mit einem Perückengehörn von außerordentlichen Abmessungen. Das Gewicht des Schädels mit der Perücke betrug im natürlichen Zustand 6070 g, nach dem Austrocknen 2020 g.
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  • 95
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    European journal of wildlife research 26 (1980), S. 75-84 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Experiments were made to study the age determination in wildlife, particularly in the roe(Capreolus capreolus L.) with the aid of experimental gerontology methods. The results obtained were correlated with those achieved by conventional age determination (external marks of the teeth, serial layers of cementum of the teeth and dry-weight of the eye lens). The results of most experiments reflect changes in the stabilisation of collagen fibres and collagen cross linking. The following tissues were studied: ear cartilage, ear skin and flexor tendon. Alteration of the solubility of collagen in neutral salt and citrate buffer: Solubility was studied with collagen from skin and cartilage. The decrease corresponded well with the different ages of donor animals. Differential thermal analysis was done with skin and cartilage: Denaturing temperature increased by 9–10° Kelvin with increasing age for skin and cartilage. Test of the tensile strenghth with flexor tendon revealed significant differences between tendons derived from animals with different ages. It increased constantly with age.
    Abstract: Résumé Tant sur le plan écologique que sur le plan économique la faune sauvage suscite un intérêt croissant. Dès lors, la détermination de l'âge revêt de plus en plus d'importance, non seulement chez les espèces domestiques et de laboratoire mais aussi chez les espèces d'animaux sauvages. En appliquant des méthodes de gérontologie expérimentale on a tenté d'indiquer de nouvelles voies qui pourraient s'avérer profitables pour l'étude des phénomènes de vieillissement chez les animaux sauvages. Chez le Chevreuil (Capreolus capreolus L.) on a examiné les modifications, en fonction de l'âge, du tissu conjonctif de la peau de l'oreille, du cartilage de l'oreille et dans le tendon fléchisseur. Afin de subdiviser le matériel expérimental en classes d'âge, une détermination de l'âge a été effectuée sur base de caractères externes de la dentition, de la stratification cémentologique des molaires et du poids sec des cristallins oculaires. L'aspect de plus en plus réticulé du collagène a pu être mis en évidence de façon particulièrement claire par la diminution progressive de la solubilité du collagène dans les fractions solubles dans un sel neutre et dans le citrate de la peau et du cartilage de l'oreille. En outre, une thermoanalyse différentielle, effectuée sur la peau et le cartilage de l'oreille, a montré que l'augmentation, en fonction de l'âge, de la température de dénaturation de ces deux tissus, déterminait une stabilisation croissante du collagène. Un test de résistance à la traction des tendons de l'extrémité antérieure montre des différences significatives en fonction de l'âge.
    Notes: Zusammenfassung In ökologischen und wirtschaftlichen Bereichen erhalten Wildtiere eine immer größer werdende Bedeutung. Daher erscheint auch die Alterskenntnis und Altersbestimmung nicht nur bei Haus- und Laboratoriumstieren, sondern auch bei Wildtieren von großer Wichtigkeit. Es wurde versucht, durch die Anwendung von Methoden der experimentellen Gerontologie neue Wege für die Alterskenntnis in der Wildtierforschung aufzuzeigen. Vom Reh (Capreolus capreolus L.) wurden altersabhängige Bindegewebsprozesse in der Ohrhaut, im Ohrknorpel und in der Beugersehne untersucht. Um das Untersuchungsmaterial in Altersgruppen einteilen zu können, wurde eine Altersbestimmung nach äußeren Merkmalen des Gebisses, der schichtweisen Anlagerung des Zahnzements und nach dem Trockengewicht der Augenlinsen durchgeführt. Die zunehmende Quervernetzung des Kollagens konnte besonders deutlich im kontinuierlichen Verlauf der abnehmenden Löslichkeit des Kollagens in den neutralsalzlöslichen und zitratlöslichen Fraktionen der Ohrhaut und des Ohrknorpels aufgezeigt werden. Weiters wurde bei der Ohrhaut und beim Ohrknorpel eine Differential-Thermoanalyse vorgenommen. Auch hier konnte durch die Erhöhung der Denaturierungstemperatur mit zunehmendem Alter in diesen beiden Geweben eine zunehmende Stabilisierung des Kollagens aufgezeigt werden. An Beugersehnen der Vorderextremität wurde ein Sehnenreißtest durchgeführt. Die Reißzeit zeigt mit zunehmendem Alter signifikante Unterschiede.
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    European journal of wildlife research 26 (1980), S. 126-132 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary In a wild boar enclosure in Austria, one individual several years old was observed smell marking and defending food. Apples were smell marked with urine and saliva. Young animals did not eat this food after having tested it by sniffing, although the marking ♂ did. The wild boar defended his feeding ground against men. In the process, he showed in a weaker or ritualised form behavioural patterns from the innate characteristics of parading, threatening and fighting. In addition, there is a report of an old boar in which acoustic impulses (the noises of a food container being used by another boar) triggered off a demonstration of rank and appropriation at the feeding ground. This trigger was more forceful than „avoidance of the enemy“. Mention is made of a case of imitation and learning in the overcoming of an obstacle.
    Abstract: Résumé Dans un parc à sangliers situé en Autriche un sanglier mâle adulte a été observé lorsqu'il procédait à des marquages olfactifs et lorsqu'il défendait sa nourriture. Des pommes furent marquées olfactivement au moyen d'urine et de salive. Contrairement au mâle en question, des sujets juvéniles n'ont pas absorbé cette nourriture apreast en avoir goûté par voie olfactive. Le verrat défendit son lieu de nourrissage contre les humains. A cette occasion il manifesta, sous une forme atténuée ou ritualisée, un comportement spécifique de défi, de menace et de combat. On fait également état d'une démonstration de rang social et d'appropriation sur une aire de nourrissage par un sanglier mâle âgé déclenchée par des stimuli acoustiques simulant le bruit provoqué par l'utilisation de mangeoires par d'autres sangliers. Ce déclencheur était plus puissant que l'„évitement d'un ennemi“. On signale un cas d'imitation et d'apprentissage lors du franchissement d'un obstacle.
    Notes: Zusammenfassung In einem österreichischen Wildschweingatter wurde ein mehrjähriger Keiler beim Duftmarkieren und Verteidigen von Futter beobachtet. Mit Harn und Speichel wurden Äpfel geruchlich markiert. Jungtiere haben dieses Futter nicht verzehrt, nachdem sie es olfaktorisch geprüft hatten, wohl aber das markierende ♂. Gegenüber Menschen verteidigte der Keiler seinen Futterplatz. Dabei zeigte er in abgeschwächter od. ritualisierter Form Verhaltensweisen aus dem innerartlichen Imponier-, Droh- und Kampfverhalten. Es wird ferner berichtet über einen alten Keiler, bei dem akustische Reize, die Geräusche eines von anderen Wildschweinen benutzten Futterbehälters, eine Rang- und Inbesitznahmedemonstration am Futterplatz auslösten. Dieser Auslöser war stärker als die „Feindvermeidung“. Ein Fall von Nachahmung und Lernen bei der Überwindung eines Hindernisses wird erwähnt.
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    European journal of wildlife research 26 (1980), S. 159-161 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Pathological-anatomical examination of dead new-born seals in the Elbe estuary established that the seal foetus swallows some of the embryonic hair (Lanugo) disposed of within the uterus before birth. These swallowed hairs contribute to the first faeces or meconium. In this connection, the causes of intestinal blockade are discussed with regard to environmental disturbances in the seal nurseries.
    Abstract: Résumé Lors de l'examen pathologique des morts-nés du Phoque de l'estuaire de l'Elbe, il a pu être montré que le foetus de Phoque avale, avant la mise-bas, des parties du pelage laineux embryonnaire (lanugo) abandonné dans l'espace intrautérin. Ces poils digérés constituent un des éléments du méconium. Dans ce contexte sont discutées les causes d'un comportement de ce méconium eu égard aux modifications de milieu observées près des bancs de sable fréquenté par le Phoque.
    Notes: Zusammenfassung Bei der pathologisch-anatomischen Untersuchung von verendeten neugeborenen Seehunden aus dem Elbeästuar konnte nachgewiesen werden, daß der Seehundfetus Teile der intrauterin abgestoßenen Embryonalbehaarung (Lanugo) vor der Geburt abschluckt. Diese abgeschluckten Haare werden zum Bestandteil des Darmpechs oder Mekoniums. Es werden in diesem Zusammenhang die Ursachen für eine Darmpechverhaltung unter Berücksichtigung von Umweltstörungen im Bereich der Seehundbänke diskutiert.
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    European journal of wildlife research 26 (1980), S. 153-158 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary From a fallow enclosure of over 20 hectares stocked with 40 animals (bucks, adult and 2-year-old does, fawns), 10 were to be removed either for transfer to other enclosures or for sale. The escape distance of the animals was so great that the task in hand could not be achieved by means of an airgun or compressed air rifle (reliable ranges 15 and 30 m respectively). With the administering of Diazepam by mouth, the escape distance could be reduced to 10 – 20 m, and sometimes less, so that a Xylazin-Ketamin mixture designed to immobilise could be used without difficulty. The general difficulties of oral medication and its effects were described in detail as well as unforeseen incidents. It was established that a dose of 30 – 40 mg Diazepam per kg of live-weight was sufficient for the required sedation.
    Abstract: Résumé Dans le but d'un transfert dans un autre enclos et pour les besoins d'une vente un prélèvement de 10 animaux — parmi les 40 que comptait un enclos à daims de plus de 20 ha — a été organisé. La distance de fuite des animaux était tellement grande que ce projet ne put être réalisé au moyen d'une sarbacane (dont la portée efficace se situe entre 15 et 30 m). Par administration orale de Diazepam la distance de fuite a put être ramenée à 10 à 20 m — voire parfois à une moindre distance encore — de telle sorte qu'un composé de Xylazine — Cétamine put être administré sans difficultés. Les difficultés générales de la médication orale de même que les effets et incidents probables sont décrits de façon détaillée. Il fut constaté qu'une dose de 30 à 40 mg de Diazepam par kg de poids du corps suffisait pour obtenir la sédation nécessaire.
    Notes: Zusammenfassung Aus einem über 20 ha großen Damwildgatter, besetzt mit 40 Tieren (Hirsche, Alt- und Schmaltiere, Kälber) sollten zwecks Umsetzung in andere Gatter sowie zum Verkauf 10 Tiere entnommen werden. Die Fluchtdistanz des Wildes war so groß, daß mittels Blasrohr bzw. Blastrohrgewehr (sichere Reichweiten 15 bzw. 30 m) die gestellte Aufgabe nicht zu erfüllen war. Durch peroralen Einsatz von Diazepam war die Fluchtdistanz der Stücke auf eine Entfernung von 10 bis 20 m, z. T. darunter, zu reduzieren, so daß ein Xylazin-Ketamin-Gemisch zur Immobilisierung ohne Schwierigkeiten zu applizieren war. Die generellen Schwierigkeiten der peroralen Medikation sowie Wirkungen und Zwischenfälle wurden eingehend beschrieben. Es wurde festgestellt, daß eine Menge von 30 bis 40 mg Diazepam kg/Kgw zur notwendigen Sedierung ausreicht.
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    European journal of wildlife research 4 (1958), S. 48-56 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
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    European journal of wildlife research 4 (1958), S. 93-99 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary The fortunate circumstance that the world of ancient Mesopotamia from the third up to the first millenium b. C. has preserved not only proofs of plastic art and reliefs, but also thousands of seal pictures, which often show animals, enables us to study the fauna of the ancient Orient much better than that of many other periods and territories. Especially about 2800, 2300, and 1300 b. C. people were very diligent with animal portraits, and naturally they chose in the first place to illustrate chase or chaseable animals. Starting with the lion the bear, wild oxen, wild sheep and goat, the oriental kinds of antelopes and stags up to the ostrich and the wild boar we find here almost complete documentary evidence of the animals to be hunted, which will be continued once more in the later Assyrian reliefs — here not treated. These testimonies are the more valuable because they are generally very animated and prove a surprising capacity of observation of these creatures.
    Abstract: Résumé C'est un fait heureux que du monde de l'ancienne Mésopotamie du troisième jusqu'au premier millénaire a. J.-C. nous sommes remis à coté des pièces justificatives de l'art plastique et de l'art du relief aussi des images de sceaux présentant très souvent des animaux, ce que nous donne la possibilité d'étudier de beaucoup mieux la faune de l'ancien Orient que celle de beaucoup d'autres époques et régions. C'est surtout vers le temps de 2800, 2300 et 1300 a. J.-C. qu'on soignait très bien le portrait d'animaux et ce n'est que trôp compréhensible que se sont surrout les représentations de chasse ou au moins des bêtes bonne à chasser qui y sont en vedette. Commancé par le lion en passant par l'ours au boeuf sauvage, le mouton et la chèvre sauvage, les espèces d'antilopes se trouvant en Asie antérieur, jusqu'au cerf, l'autruche et le sanglier; on y trouve une documentation presque complète sur tous les bêtes bonne à chasser; documentation qui sera encore continuée dans les reliefs de l'ancien Assyrie, quoique ces derniers ne soient pas traités dans cet ouvrage. Ces témoignages sont d'autant plus précieux, qu'ils font le plus souvent épreuve d'une grande vivacité et qu'ils accusent un talent d'observations étonnant chez leurs créateurs.
    Notes: Zusammenfassung Der glückliche Umstand, daß die Welt Altmesopotamiens vom 3. bis zum 1. Jahrtausend v. Chr. uns neben Belegen der Vollplastik und Reliefkunst Tausende von Siegelbildern aufbewahrt hat und auf diesen häufig Tiere abgebildet sind, ermöglicht es uns, die Fauna des Alten Orients weit besser studieren zu können als die vieler anderer Zeiten und Gebiete. Besonders um 2800, um 2300 und um 1300 v. Chr. hat man sich um Tierporträts sehr bemüht, und hierbei steht verständlicherweise das Jagdbild oder zum mindesten das jagdbare Wild im Vordergrund. Vom Löwen angefangen über Bär, Wildrind, Wildschaf und-ziege, die vorderasiatischen Antilopenarten und den Hirsch bis hin zum Strauß und das Wildschwein wird hier eine nahezu vollständige Beurkundung der jagdbaren Tiere geboten, die dann in den — hier nicht behandelten —spätassyrischen Reliefs noch einmal fortgesetzt wird. Diese Zeugnisse sind um so kostbarer, als sie meist von großer Lebendigkeit sind und eine erstaunliche Beobachtungsgabe ihrer Schöpfer beweisen.
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