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  • Springer  (92,149)
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  • 1980-1984  (138,949)
  • 1925-1929  (8,986)
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  • 101
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    Bulletin of mathematical biology 42 (1980), S. 282-282 
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  • 102
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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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  • 103
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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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  • 104
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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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  • 105
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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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  • 106
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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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  • 107
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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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  • 108
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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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  • 109
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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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  • 110
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    Bulletin of mathematical biology 42 (1980), S. 747-748 
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  • 111
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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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  • 114
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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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  • 115
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    Bulletin of mathematical biology 45 (1983), S. 11-20 
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    Notes: Abstract This paper is concerned with a generalization of the simple epidemic model in which the infective population is partitioned intom classes, each of specific infectiousness. Attention is restricted, however, to the case where all the meeting rates between two individuals are equal to each other. Both deterministic and stochastic versions are examined. In either case the development in time of the epidemic process is investigated by exploiting a connection with the standard simple epidemic model. Finally, it is shown that the technique used also applies to a similar model for the spread of information.
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  • 116
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    Bulletin of mathematical biology 45 (1983), S. 33-40 
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    Notes: Abstract For each rooted binary tree witht labeled terminal vertices (leaves) a natural number can be assigned uniquely. Unrooted trees witht labeled terminal vertices andt-2 unlabeled internal vertices of degree 3 can also be numbered uniquely using the same convention. Rooted trees in which the hights of the internal vertices are rank ordered are also considered. Applications to problems in taxonomy are discussed.
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  • 117
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    Bulletin of mathematical biology 45 (1983), S. 41-50 
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    Notes: Abstract Expressions and numerical values for hematocrit reduction are calculated as blood flows from a cylindrical feeding tube into a cylindrical capillary at a right-angle branch. Blood is considered to consist of two Newtonian fluids, plasma and red cell suspension, which have equal densities but different viscosities. The concentration profile of the red cells is concluded to depend on the size of the feeding tube. An estimate for the thickness of the plasma layer adjacent to the wall is obtained.
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  • 118
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    Bulletin of mathematical biology 45 (1983), S. 51-67 
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    Notes: Abstract Asimple model system of two self-reproducing objects is considered. A set of equations, similar to Eigen's equation, describing competition of these objects is derived and analyzed under the effect of an ‘ecological constraint’. The relation with other constraints used in the literature is discussed.
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  • 119
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    Bulletin of mathematical biology 45 (1983), S. 69-90 
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    Notes: Abstract A membrane with an arbitrary distribution of fixed charges inside and on its surfaces is considered. A procedure for calculating the local electrostatic potential at an arbitrary point of the system is described and its validity discussed. This procedure is based on the linearization of the 3-dimensional Poisson-Boltzmann equation around an exact 1-dimensional solution.
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    Bulletin of mathematical biology 45 (1983), S. 103-116 
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    Notes: Abstract In this, the first of a series of papers on stochastic and deterministic non-linear allometric growth models, a deterministic model is proposed which generalizes the widely applicable classical linear model of Huxley and Needham. There aren types of producers, each type depositing a product which accumulates monotonically in the environment. Producers interact via a mass action law satisfying an optimality condition. Coefficients may be interpreted as competition between the various producer types in the usual Volterra sense. An ideal coral reef is studied in which then species of coral polyps lay down aragonite calcium carbonate in building the reef framework. This deterministic model predicts that younger reefs are strongly unstable relative to initial species abundance, while older reefs grow in the classical sense of Huxley and Needham, asymptotically, as time goes to infinity.
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    Bulletin of mathematical biology 45 (1983), S. 151-153 
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    Notes: Abstract First-order spatial gradients are reliquished in the Schrödinger-Bloch equation for bacterial chemotaxis if and only if the flux coefficient-motility ratio equals 2, the precise value measured in recent experiments onEscherichia coli attracted by oxygen. Moreover, for δ/μ=2 the Schrödinger-Bloch function Ψ is simply equal to the number of bacteria cells per unit volume divided by the chemoattractant concentration.
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    Bulletin of mathematical biology 45 (1983), S. 169-192 
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    Notes: Abstract A mathematical formulation useful in characterizing the effects of light on the pupal eclosion rhythm of the fruit flyDrosophila pseudoobscura is presented. It is based upon the premise that the underlying pacemaker oscillator behaves in a manner analogous to a customized version of a phase-locked loop circuit. Theoretical analyses supplemented with numerical simulations reveal that this phase-locked loop approach yields a concise mathematical characterization which is quite comprehensive in its scope, yet surprisingly accurate in the detail with which it can be used to successfully predict observed experimental results.
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    Bulletin of mathematical biology 45 (1983), S. 155-168 
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    Notes: Abstract Pointwise upper and lower bounds for the solution of a class of nonlinear problems arising in the steady-state finite cable model of cell membranes are presented. Simple analytical bounding curves are obtained for an illustrative example in the theory of nerve membranes.
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    Bulletin of mathematical biology 45 (1983), S. 209-227 
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    Notes: Abstract Single-species reaction-diffusion models are analyzed to determine the effect of various diffusion mechanisms on species persistence or extinction.
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    Bulletin of mathematical biology 45 (1983), S. 401-408 
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    Notes: Abstract A restriction is imposed on the number of particles that can possibly move at any time from a compartment, so that any other particles present in the compartment must wait until such particles have moved out. The equations for such a system are formulated and the solution is given for a single compartment system; increased variability of the compartmental particle count is one effect of this restriction.
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    Bulletin of mathematical biology 45 (1983), S. 323-345 
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    Notes: Abstract Two classes of dose-effect models for cell killing (additive damage and independent effects) are developed under alternative hypotheses about the damage that leads to cell death. Generalized models, along with specific models for cell killing after exposure to a specific cytotoxicant, are used to make predictions about the effects of sequential or simultaneous exposure to different cytotoxicants. It is demonstrated that with the additive damage models developed one can adequately account for the combined effects of the cytotoxicants considered. Theoretical results are presented which suggest that after simultaneous exposure of cells to low total doses (〈0.1 Gy) of different ionizing radiations, use of the conventional relative biological effectiveness approach to predict cell killing risks is unnecessary; cell killing risks can adequately be determined by assuming the effects of the different radiations to be independent. Also, for simultaneous exposure of cells to total doses of different radiations much larger than 0.1 Gy, use of the conventional RBE approach to arrive at cell killing risk could lead to overestimation of the risk.
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    Bulletin of mathematical biology 45 (1983), S. 347-400 
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    Notes: Abstract A predator which is preying on a model-mimic system can choose either the single-trial strategy or a multi-trial strategy as its behavior in learning to prudently harvest such a prey system. In this learning behavior, an important and often-posed problem is to determine which among these two strategies is better suited for the predator and why one is preferable over the other. We present in this article, using Markov chain methods, an extensive analysis of these strategies (and also of eat-everything, strategy). We conclude that the multi-trial strategy is the one that the predator should adopt (but we will also describe the situations when the single-trial strategy seems to be better). Our conclusions are based on the comparisons of quantities such as the mean benefit to the predator, energy derived by a predator from the model-mimic system and (a newly introduced notion of) contagion in eating mimics and models (these quantities are computed for different strategies). The first two quantities are functions of the abundancep and noxiousnessb of models. The contagion is a function of onlyp; and, though independent ofb, it is also in support of multi-trial, strategy. We introduce, in the present context, a biological analog of the d'Alembert principle and also derive functions describing the influences of eating a specified type of prey at a given time on eating any type of prey at a later time. Various results of Estabrook-Jespersen (single-trial strategy) and Bobisud-Potratz (multi-trial strategy) are re-derived as special cases of our more general results. A central limit theorem under the eat-everything strategy is given.
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    Bulletin of mathematical biology 45 (1983), S. 431-435 
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    Bulletin of mathematical biology 45 (1983), S. 425-430 
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    Notes: Abstract We consider the one-dimension (one-compartment) exponential model using a diffusion process approach. In particular, we summarize the known results in the case where the stochastic component of the model is a Gaussian white noise process with mean zero and variance σ2. Finally, we briefly illustrate a number of cases where similar forms of model arise.
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    Bulletin of mathematical biology 45 (1983), S. 467-482 
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    Notes: Abstract The surfaces of many cells are viscous fluids; consequently, most membrane proteins are able to diffuse laterally, in a more or less random fashion, with diffusion coefficients typically of order 10−10 cm2/sec. If a molecule (ligand) in solution outside the cell and a protein molecule on the surface (receptor) each have two or more sites at which they can interact with one another, large, branched receptor-ligand networks can form on the cell surface by virtue of the chemical interactions that surface fluidity permits. Evidence from a variety of systems indicates that such receptor clustering plays a role in the sequence of events leading to cellular activity. This paper describes a number of mathematical problems that arise in the analysis of experiments in which clustering occurs. I begin by reviewing methods for finding the time evolution of the cluster size distribution function in terms of reaction rate constants. The methods solve an essentially infinite system of coupled nonlinear differential equations. Next, the rate constants are analyzed, the Brownian motion problems that arise in attempting to understand ligand recognition are described and relevant experimental systems are discussed. Finally the notion of ligand as a signal amplifier is introduced—an idea that emerges naturally from the requirement that receptors be clustered for a finite amount of time before a signal can be transmitted.
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    Bulletin of mathematical biology 45 (1983), S. 555-569 
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    Notes: Abstract The covariances among the populations of distinct compartments are studied for the multi-compartmental birthless death-migration-immigration process. The important role played by the transition matrix of the deterministic process is underlined. Several examples are discussed.
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    Bulletin of mathematical biology 45 (1983), S. 483-506 
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    Notes: Abstract Qualitative theory for multidimensional stochastic dynamical models $$\dot x = f(x, \xi )$$ is presented where the random influences ξ may be white or colored, i.e. a (possibly bounded) diffusion process. We concentrate on transience, stationary solutions and boundary behavior and discuss a set-up for reliable simulations. The method consists in associating a deterministic control system where the (approximate) controllability properties determine the qualitative behavior of the stochastic system. Applications to some biological systems indicate the usefulness of qualitative theory in life sciences.
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    Bulletin of mathematical biology 45 (1983), S. 599-603 
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    Notes: Abstract We study some linear stochastic differential equations in Hilbert spaces.
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    Bulletin of mathematical biology 45 (1983), S. 591-597 
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    Notes: Abstract In this article we show how linearity with respect to the output of a stochastic dynamic model can be exploited in order to simplify the computation of moments or conditional moments. The results are presented for two examples, one of which includes delays. This feature is often encountered in biological models.
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    Bulletin of mathematical biology 45 (1983), S. 873-874 
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    Bulletin of mathematical biology 45 (1983), S. 869-872 
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    Notes: Abstract In the derivation of the biomass distribution function for an ecological population critical use is made of an energetic constraint on the maximization of biomass diversity. The nature of this constraint is explored in detail using Kleiber's relation σ(m)=cm γ between animal metabolic rate σ(m) and body weightm in conjuction with the Prigogine-Wiame thermodynamic paradigm for specific entropy production in biological stationary states. These two inputs fix the energetic constraint on the maximization of biomass diversity to be the constancy of the mean metabolic rate of the ecosystem. The resulting biomass distribution function is tested against observational data.
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    Bulletin of mathematical biology 45 (1983), S. 875-875 
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    Bulletin of mathematical biology 45 (1983), S. 901-915 
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    Notes: Abstract A system of mixed integrodifferential and partial differential equations for an agestructured predator-prey system is studied here. The predator eats all ages of prey, but more of the very young and very old than of the intermediate ages. The existence of periodic solutions corresponding to stable coexistence is proved for a suitable range of parameters by bifurcation theory.
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    Bulletin of mathematical biology 45 (1983), S. 877-900 
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    Notes: Abstract In this paper, stability of two-prey, one-predator communities is investigated by Lyapunov's direct method and Hopf's bifurcation theory. Three patterns of three-species coexistence are possible. A globally stable non-negative equilibrium exists for the system even if two competing prey species without a predator cannot coexist. The stable equilibrium bifurcates to a periodic motion with a small amplitude when the predation rate increases. It is also shown that a chaotic motion emerges from the periodic motion when one of two prey has greater competitive abilities than the other. This predator-mediated coexistence can be realized by the intimate relationship between preferences of a predator and competitive abilities of two prey.
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    Bulletin of mathematical biology 45 (1983), S. 917-930 
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    Notes: Abstract A non-linear stability analysis using a multi-scale perturbation procedure is carried out on the practical Thomas reaction-diffusion mechanism which exhibits bifurcation to non-uniform states. The analytical results compare favourably with the numerical solutions. The sequential patterns generated by this model by variations in a parameter related to the reaction-diffusion domain indicate its capacity to represent certain key morphogenetic features required in a recent model by Kauffman for pattern formation in theDrosophila embryo.
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    Circuits, systems and signal processing 2 (1983), S. 341-360 
    ISSN: 1531-5878
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    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract This paper presents a new method for estimating the coefficients of autoregressive moving-average parameters of stationary time series. The method is based on computing the sample autocorrelations of the given time series and fitting an ARMA model so as to approximate the partial autocorrelations in a least-squares sense. When the given time series are characterized by spectral zeroes near the unit circle, they tend to have relatively long sequences of nonzero partial autocorrelations; hence the new method is especially effective in such cases. This paper contains a derivation of all necessary mathematical details, as well as several numerical examples illustrating the performance.
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    Circuits, systems and signal processing 2 (1983), S. 3-34 
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    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Summary of Part I The present article represents a survey of a new frequency domain approach to the feedback system design problem. Although the theory applies to the general multivariate case and, in fact, much of the theory can be extended to a general ring theoretic setting for the purpose of the present exposition we will restrict ourselves to the single-variate case wherein the simple algebraic nature of the new theory is most readily apparent. In Part I1 we introduced the concept of a stable rational fractional representation for a feedback system and derived an asymptotic design theory therefrom. This included a complete parameterization for the set of compensators which stabilize the system under appropriate tracking and/or disturbance rejection constraints. Moreover, expressions for the feedback system gains of the resulting system which are linear (actually affine) in the underlying design parameter are obtained. As such, the process of choosing a specific design within this set to meet additional specifications is greatly simplified. In Part II we investigate a number of these constraints. These include the robust design problem, transfer function design, the pole placement problem, the simultaneous design problem, and the problem of designing a stable stabilizing compensator.
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    Circuits, systems and signal processing 2 (1983), S. 99-117 
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    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract The anti-sidetone telephone circuit is a frequency-independent passive reciprocal 3-port whose scattering matrix between three prescribed resistive terminations (transmitter, receiver, line) meets a certain specification. In their 1920 paper, Campbell and Foster (CF) showed that the prescribed 3-port can be realized as a lossless 4-port consisting in two 3-winding transformers closed on one resistance (the balancing network). If one (two) relations are imposed between the terminating resistances of the 4-port, realizations involving a single 3-winding (2-winding) transformer are available, and the resulting 136 (38) distinct realizations have been listed by CF. In this paper, we reestablish the CF-results (which were stated almost without proof in their paper and have never been rediscussed in the literature) and present a genetic classification of their 136 + 38 circuits. Recently, a realization of the anti-sidetone 3-port containing more than one internal resistance (in addition to the balancing network, a light-emitting diode serves to illuminate the dial) has been described by D. R. Means; in this paper, we present a complete characterization of that wider class of circuits.
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    Circuits, systems and signal processing 2 (1983), S. 155-160 
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    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract A differential operational amplifier with reverse switched and fixed capacitors produces a semi-nonsingular sampled data system which leads to a delayed sample and hold signal. Such a device can be suitably applied to a compensating resonant low-pass filter which is derived within theclass of Rader-Gold transforms. The resonant low-pass filter application demonstrates that analog transfer functions with bounded spectrums can be converted to accurate digital spectrum counterparts without pole-zero decompositions.
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    Circuits, systems and signal processing 2 (1983), S. 239-253 
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    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract Multivariable positive real functions whose polynomial derivatives are reactance functions — a characteristic not possible in the case of single-variable positive real functions — are discussed. It is shown that the input impedances of certain cascaded multivariable networks belong to this class. Necessary and sufficient conditions for a multivariable positive real function with unity degree in each variable to be the input impedance of a resistively-terminated cascade of two lossless two-ports in mutually exclusive variables and separated by a series inductor or a shunt capacitor in another variable are discussed.
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    Circuits, systems and signal processing 2 (1983), S. 311-326 
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    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract One form of the singular systemAx′+Bx=f is considered. The analytic solution, perturbation, and numerical solution of this form are examined. A class of systems which may be transformed into this form without altering these properties is characterized.
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    Circuits, systems and signal processing 2 (1983), S. 391-420 
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    Notes: Abstract The least-squares lattice filter is used to implement an infinite-impulse-response adaptive filter for the enhancement of narrowband signals in the presence of white or finitely correlated noise. The advantages of infinite impulse response filters for adaptive line enhancement are discussed. The performance of the proposed technique is illustrated by simulation results.
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    Circuits, systems and signal processing 2 (1983), S. 469-485 
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    Notes: Abstract This paper describes a new design method of inductance simulation for switched-capacitor (SC) filters based on the VIS-SC concept. The resulting circuits have not only the excellent sensitivity behavior of VIS-SC filters, but also the low sensitivity to the main parasitics occuring in the MOS integrated circuit, i.e., the parasitic capacitances between the bottom plates of the implemented capacitors and substrate. As examples, a sixth-order band-pass and a sixth-order band-stop elliptic filter transformed from a third-order low-pass are given. Experimental results agree very well with theory. A brief analysis is given of certain parasitic effects in band-stop filters at the Nyquist frequency.
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    Circuits, systems and signal processing 2 (1983), S. 1-2 
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    Circuits, systems and signal processing 2 (1983), S. 89-98 
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    Notes: Abstract An upper bound on the order of complexity of a solvable RLC-nullor network is found.
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    Circuits, systems and signal processing 2 (1983), S. 131-154 
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    Notes: Abstract In an envelope-constrained filtering problem with uncertain input the set of possible input waveforms and the set of permissible output waveforms are each defined by envelope constraints (time domain inequalities). The object is to find the optimal (minimal norm) inpulse response for which every waveform in the input envelope evokes a response in the output envelope. The problem is solved by extending earlier results for a single specified input. The solution is further extended to allow for unknown-but-bounded errors in the filter realization.
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    Circuits, systems and signal processing 2 (1983), S. 193-201 
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    Notes: Abstract After selecting the most suitable model for the class of two-dimensional quarter-plane-causal, recursive, and separable in denominator (CRSD) filters, a procedure for realizing a cascade system of such filters is developed. The realization utilizes the individual CRSD models constituting the cascade system. An example is given to further illustrate the technique.
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    Circuits, systems and signal processing 2 (1983), S. 269-276 
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    Notes: Abstract In this paper we present an approach for improving the output signal-to-noise power ratio of a discrete-time matched filter by employing a continuous-time filter, even though the continuous-time signal input is imperfectly known. It is shown that is it possible to design a continuous-time filter which is robust to inexact knowledge of the signal input; moreover, the robustness property does not severely compromise performance. In fact, it is shown that the resulting filter possesses an output signal-to-noise power ratio which upper bounds that of the discrete-time filter.
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    Circuits, systems and signal processing 2 (1983), S. 285-309 
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    Notes: Abstract The practical issue addressed in this paper is the automated design of FIR multiband digital filters. The specific theoretical filter-design problem addressed is what to do over the transition regions if a min-max design criterion is adopted. The technique suggested consists of formulating the design over the entire band [0,π]. Advantages and disadvantages of this approach versus the use of “don't care” bands are examined. Specific comparisons pertaining to FIR multiband design are presented. The specific contribution of the paper is twofold: (i) A suggestion for the type of functions to use as an objective over the transition regions if a full band [0,π] min-max formulation is to be used. (ii) A design technique for multiband FIR which appears useful in a CAD context. This technique gives results comparable to those obtained with the “don't care” band approach. However, the new procedure requires less user interaction and is thus much easier to automate.
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    Circuits, systems and signal processing 2 (1983), S. 361-386 
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    Notes: Abstract A theorem is introduced which is useful in deriving equivalent multirate filter structures. Frequency responses of multistage multirate filters are derived and defined by deriving their equivalent one-stage filters. A design principle is proposed to reduce filtering requirements at each stage and move the filter operations to low-sampling-rate stages and thus result in a lower arithmetic rate. Optimum FIR and IIR multistage multirate filter designs are developed based on this principle. The new design has a one-point passband specification for each decimator and/or interpolator stage resulting in a wider transition region and lower filter order. Examples are given to explain the design procedure, and comparisons are made to show the superiority of the new filters.
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    Circuits, systems and signal processing 2 (1983), S. 487-516 
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    Notes: Abstract A system concept expected to improve sonar multiple target detection and classification performance in severe directional interference environments is presented. Adaptive nulling of undesired strong interference sources and detection of desired weak sources are achieved by utilizing constrained adaptive processing techniquestogether with conventional processing techniques. The adaptive processing functions are incorporated in the overall system architecture in a manner which maintains the computational complexity and storage requirementslinearly proportional to the product of the number of interference sources and the number of adaptive weights per interference source. In addition, a detailed discussion is provided concerning the importance of certaina priori assumptions on constrained adaptive algorithm performance.
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    Bulletin of mathematical biology 45 (1983), S. 1-9 
    ISSN: 1522-9602
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    Topics: Biology , Mathematics
    Notes: Abstract The urn model discussed in part is generalized so that the random depletion of balls from the urn in any cycle is not necessarily the same as the reinforcement in that cycle. This model is applied to an urn containing balls of three colors (white, red, black) for which the black balls always receive reinforcements, whereas there is only one cycle in which red balls are added. Experimental data are considered in which red balls correspond to radioactive iodine atoms, black balls to stable iodine atoms and white balls to empty space, all relating to the thyroid gland. Half-life periods for the radioactive iodine in relation to the time of uptake (ten years, fifteen years, etc.) are considered.
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    Bulletin of mathematical biology 45 (1983), S. 21-31 
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    Notes: Abstract Kinetic equations for the action of a reagent on a population which is increasing by Gompertzian growth are solved by a combination of analytical and numerical methods for both dilute distributions and cellular aggregates. For the aggregates an empirical function controlling extent of diffusion is used with external reagent concentration held constant, and the effective diminution of reagent activity caused by aggregation is related to the extent of penetration by diffusion. Diffusion from the centre is considered. Solutions with time-dependent reagent concentration are obtained for a distribution, and the effect of successive inputs of reagent studied.
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    Notes: Abstract Bilayer lipid membranes consist of an inner hydrocarbon tail region with the hydrophilic polar heads on either side. The order-disorder transition in the hydrocarbon tail reigon, from liquid crystalline (fluid) to gel state, is characterised in terms of a Landau-de Gennes description, in which the effect of an external electric field is incorporated through its description, in which the effect of an external electric field is incorporated through its interaction with the surface charges on the bilayer (placed as it is in an ionic medium) or with the polar heads. Biological implications of such a phase transition, for excitable membranes, resides in a model wherein ion channels (taken to be composed of protein bundles) are postulated to be surrounded by lipid molecules in the fluid phase when the membrane is in its resting state, while surface charges and/or the polar heads of the lipid molecules responding to an electric stimulus, if of adequate magnitude, induces a transition in the hydrocarbon tail region of the (boundary) lipid surrounding the ion channels from the liquid crystalline (fluid) to the crystalline (gel) phase which, in turn, through coupling with the relevant modes of the protein bundles, results in the opening of the ion channels, provinding thereby a mechanism for the desired response.
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    Bulletin of mathematical biology 45 (1983), S. 117-138 
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    Topics: Biology , Mathematics
    Notes: Abstract Concepts of the uniqueness of the amino acid sequences of proteins were defined in a prior report (Saroff, H. A. and F. A. Kutyna. 1981. “The Uniqueness of Protein Sequences: A Monte Carlo Analysis.”Bull. math. Biol. 43, 619–639), which presented a detailed discussion ofi-uniqueness, i.e. the tendency of small peptides to be repeated within an amino acid sequence of a protein. We now report on the quantitative analysis ofo-uniqueness, which evaluates the tendency of small peptides to be repeated amongst different proteins, usually of a single species. A detailed analysis of theo-uniqueness of several proteins is presented to illustrate the method and the range of values encountered. Uniqueness data on sequences of human proteins in a data bank of sequences containing about 32,500 amino acids are made available in the form of a microfiche. Analysis of biologically active subsequences such as the angiotensins and the enkephalins suggest a tendency of the subsequences contributing to the property ofo-uniqueness to cluster in portions of the parent protein sequence which are biologically active. This property may provide a general method for predicting biologically active areas of proteins. Current data may already be adequate to permit useful predictions, and the rapidly accumulating and interrelated new data on nucleic acid and protein sequences will further enhance the power ofo-uniqueness analysis.
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    Bulletin of mathematical biology 45 (1983), S. 143-149 
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    Notes: Abstract In this note we examine Eigen's nonlinear rate equations for the relation of coupled biomacromolecules. We obtain an exact solution to the equations for constant overall population densities and constant rate parameters. We conclude that there is only one stationary solution where all molecular species coexist when they are coupled by mutation.
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    Bulletin of mathematical biology 45 (1983), S. 229-237 
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    Notes: Abstract Previously developed light absorption models have treated the effective quantity of light-absorbing material within the experimental environment as a constant, i.e. a parameter. These models are, however, probabilistic in nature and are properly applied and interpreted only in a statistical sense. Thus, it is clearly logical to regard the effective quantity of light-absorbing material to be a random variable. In this paper an asymptotic distribution is derived for this random quantity, and it is shown how this distribution may be incorporated into present models. These results may be applied to light absorption by plant and crop canopies as well as to liquid or solid media. Furthermore, previous models are based upon the assumption that light is parallel, or effectively so, as for solar light. Such models may be inadequate for an artificial (laboratory) environment which utilizes point source light. Present models for estimating light interception and radiation intensity are modified so as to accommodate a proximate point source of light. Numerical examples are included to illustrate the theory.
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    Bulletin of mathematical biology 45 (1983), S. 239-257 
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    Notes: Abstract This paper presents an exact analysis of a mutually coupled relay oscillator based on a method orignated by Tsypkin. Limit-cycle frequencies and phases can be determined exactly using this method, unlike other approximate methods based on describing functions and harmonic balance techniques. A new method of exact determination of limit-cycle stability is also shown to give excellent agreement with simulation studies. Different types of intercoupling are shown to give different stability conditions, and these are discussed in relation to gastrointestinal (GI) smooth muscle modelling. GI tract electrical activity has previously been modelled using bidirectionally coupled nonlinear oscillators, and the results of the present analysis of relay oscillators is compared with other studies using van der Pol dynamics.
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    Bulletin of mathematical biology 45 (1983), S. 269-285 
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    Notes: Abstract Information about the way of branching of dendritic arborizations may be obtained by comparing the frequency distributions of observed branching patterns with theoretical distributions based on well-defined growth models. Two models usually get much attention in geomorphological and (neuro)biological studies, viz. terminal growth and segmental growth. Formulae to construct the exact probability distributions for both growth models are presented. It is shown that ranking and lumping of the individual branching patterns enable the analysis of very large arborizations with relatively few data. The application of the Kolmogorov goodness-of-fit test for discrete distributions to the analysis is discussed.
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    Bulletin of mathematical biology 45 (1983), S. 295-309 
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    Notes: Abstract An autonomous system of two differential equations with an asymptotically stable steady state is considered. It is shown that there exists a class of time delays which preserves the stability of such a steady state. The charactristic return time (or decay rate) for the solutions to approach the steady state is estimated using the variational system for the perturbations.
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    Circuits, systems and signal processing 2 (1983), S. 77-87 
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    Notes: Abstract In this paper we generalize recent theorems concerning the existence (and algorithms for obtaining) a power-series-type expansion for a nonlinear system's outputs in terms of its inputs. The results given here are directly applicable to a much larger class of systems.
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    Circuits, systems and signal processing 2 (1983), S. 119-128 
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    Notes: Abstract Explicit conditions required to be satisfied by the numerator and denominator polynomial coefficients of a magnitude-squared rational response function, ¦S21(jωi, jω2) ¦2, so that it might approximate an ideal low-pass characteristic along any straight line in the plane through (0,0) in a maximally flat manner, are obtained. The condition for attenuation along all radial directions through (0,0) is expressed in terms of the positivity of a form in two variables. The technique is easily extended to the multidimensional case and can be used to design filters other than those of the low-pass type. The theory could be used to design lumped-distributed and variable-parameter filters.
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    Circuits, systems and signal processing 2 (1983), S. 179-192 
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    Notes: Abstract Results are given concerning the existence and other properties of Volterralike input-output expansions for discrete-time systems whose inputs and outputs are defined on the time set {0,1,2,}. The results, which establish the existence of (and show how to obtain) a locally convergent input-output expansion for a very large class of systems, are along the lines of those reported recently by this writer for continuous-time systems. With regard to one of the theorems given here, new ground is broken in that the theorem directly addresses the case where the nonlinear part of the system need not be assumed to be memoryless. Systems of the kind considered arise, for example, in the area of communication channel modeling for digital data transmission.
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    Circuits, systems and signal processing 2 (1983), S. 259-268 
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    Notes: Abstract Using fixed-point arguments, existence and uniqueness results are obtained for the joint resistance of infinite positive operator networks with noncommuting operators in the branches. Explicit representations for the joint resistance are given using the geometric mean of positive operators.
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    Circuits, systems and signal processing 2 (1983), S. 277-284 
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    Notes: Abstract Convenient matrix formulas for calculating the sensitivities of multiplier coefficients of the impulse and step responses of arbitrary digital network configurations, as given by their flow graphs, are presented.
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    Circuits, systems and signal processing 2 (1983), S. 327-339 
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    Notes: Abstract This paper presents new results for predictive compression of signal samples, based upon spectral observation. The formulation emphasizes the inherent presence of a deterministic signal model and will accommodate time-varying models and time- and signal-dependent error bounds. Transmission of predictive error residuals instead of the samples themselves is shown to be identical in structure to linear predictive coding; although additionally applicable where available stochastic signal models may be inadequate. Sample deletion, when prediction error is within a chosen bound, offers a real time compression method of particular importance to measurement and control applications.
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    Circuits, systems and signal processing 2 (1983), S. 445-467 
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    Notes: Abstract This paper considers certain useful approximations which can be obtained by doubly terminated two-variable cascade-separable networks. Since such networks can be transformed into 2-D wave digital filters, these approximations provide useful magnitude responses in the 2-D digital domain, also. Two approximation methods are discussed, and these can produce near quadrantal symmetry.
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    European journal of wildlife research 26 (1980), S. 1-11 
    ISSN: 1439-0574
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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 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    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 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    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 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    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 
    ISSN: 1439-0574
    Source: Springer Online Journal Archives 1860-2000
    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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    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 29 (1983), S. 48-54 
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    Description / Table of Contents: Summary A full translation of Y Naw Helwriaeth is presented for the first time in German, and the contents, sources and significance of this old Welsh hunting code are discussed in detail. Y Naw Helwriaeth is a unique conflation of old Welsh, Anglo-Norman and Middle English sources, which was compiled in the mid sixteenth century byGruffudd Hiraethog.
    Abstract: Résumé Une traduction complète et fidèle en allemand du »Y Naw Helwriaeth« est présentée pour la première fois et le contenu, les sources et la signification de cet ancien code de chasse du Pays de Galles font l'objet d'une discussion approfondie. »Y Naw Helwriaeth« constitue une compilation unique d'éléments provenant de sources galloises anciennes, anglo-normandes et moyen-anglaises rassemblés au 17ème siècle parGruffudd Hiraethog.
    Notes: Zusammenfassung Eine vollständige und getreue Übersetzung von Y Naw Helwriaeth wird zum ersten Mal auf Deutsch vorgestellt, und der Inhalt, die Quellen und die Bedeutung dieses alten walisischen Jagdkodexes werden eingehend diskutiert. Y Naw Helwriaeth sind eine einzigartige Kompilation aus alten walisischen, anglo-normannischen und mittelenglischen Quellen, die mitten im 16. Jahrhundert vonGruffudd Hiraethog zusammengestellt wurde.
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    European journal of wildlife research 29 (1983), S. 62-62 
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    European journal of wildlife research 29 (1983), S. 95-110 
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Rye, barley, potatoes, turnips and maize were cut back with scissors, by one-third and two-third to simulate browsing by game; in each case all plants in a plot were cut back by 30 % and 60 % respectively. In addition, the pulling-out of the plants by game was simulated, at rates of 80 %, 40 % and 20 %. Generally, in all cultivated plants, there were significant reductions of yield, almost exclusively in those plots in which 80 % of the plants had been removed. An influence on the ability of the plants to recover is exercised by the weather of the year and the timing of the damage. Analyses of the structure of the cereal crops showed that the influence on the stand density of the crop is greater than on the number of the heads per are or on the weight of 1000 heads.
    Abstract: Résumé Pour les besoins d'une simulation, du seigle, de l'orge, des plants de pommes de terre, des betteraves et du maïs furent recoupés aux 1/3 et aux 2/3 à raison de 30, 60 et 100 % des plantes d'une parcelle. En outre, on simula l'arrachage de plantes par le gibier à raison de 20, 40 et 80 %. Des pertes significatives furent généralement enregistrées parmi toutes les cultures dans les seules parcelles où 80 % des plantes avaient été écartées. La faculté de régénération des plantes est influencée par les conditions climatiques ayant prévalu au cours de l'année ainsi que par l'époque à laquelle les dégâts se sont situés. Des analyses de la récolte des céréales montrent que l'influence sur la densité des brinsest plus importante que sur le nombre de grains par are et par poids de mille grains.
    Notes: Zusammenfassung Roggen, Gerste, Kartoffeln, Rüben und Mais wurden zur Simulation des Wildverbisses mit Scheren um 1/3 und 2/3 zurückgeschnitten; jeweils alle Pflanzen, 60 % und 30 % der Pflanzen einer Parzelle. Zusätzlich wurde das Herausziehen der Pflanzen durch Wild simuliert, und zwar in den Stufen 80 %, 40 % und 20 %. Durchgehend in allen Kulturpflanzen zeigten sich signifikante Ertragsverluste fast ausschließlich in den Parzellen, in denen 80 % der Pflanzen entfernt worden waren. Einen Einfluß auf die Regenerationsfähigkeit der Pflanzen haben die Jahreswitterung und der Zeitpunkt des Schadens. Ertragsstrukturanalysen in Getreide zeigten, daß der Einfluß auf die Bestandesdichte größer ist als auf Kornzahl je Ähre und Tausendkorngewicht.
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    European journal of wildlife research 29 (1983), S. 120-122 
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary A report is given on the occurrence of feral farm minks escaped from farms in Schleswig-Holstein. 230 captures, killings and sightings have been recorded since 1950. It is uncertain if there are already existing self-sustaining populations.
    Abstract: Résumé Des visons échappés d'élevages s'observent en parcours libre dans le Schleswig-Holstein depuis 1950. 230 captures, tirs ou observations ont été enregistrés jusqu'a présent. Il n'est pas établi clairement s'il existe pour autant des populations stables et autonomes.
    Notes: Zusammenfassung Entwichene Farmnerze kommen in Schleswig-Holstein seit 1950 im Freiland vor. 230 Fänge, Erlegungen und Beobachtungen wurden bisher registriert. Es ist unklar, ob bereits stabile, sich selbst erhaltende Populationen bestehen.
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    European journal of wildlife research 29 (1983), S. 111-119 
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary Court hunting in the Dukedom of Westfalia in the time of the Electors of the House of Wittelsbach (1583–1761) required a large number of dogs talented and well-trained in many respects. Insofar as these were controlled by the staff of the Westfalian hunting office, the Electoral Oberkellner office in Arnsberg covered the maintenance of the pack. The costs amounted to around 3000 Reichstaler per year. In the course of the development of full state sovereignty, “dog-service” was introduced, involving around 90 farms, each of which either had to take and care for one of the Elector's dogs without payment or otherwise had to pay “dog-money” of 1 Reichstaler a year. Apart from farmers, the executioners and the bailiffs and several monasteries were also obliged to do “dog-service”, which in general was fulfilled by cash payments. The executioners paid 64 Reichstaler and the monasteries 252 Reichstaler a year. A particular form of “dog-service” was the dog-loan. Farmers and burghers were arbitrarily forced under threat of penalties to lend their dogs, insofar as they were suitable, to the hunts organized by the Elector or by the hunting office, without payment. Sporadic opposition to the “dog-service” had no success. It was only lifted, with all the other hunting burdens by a law, the Prussian Diocharge Act (Ablösungsgesetz) in 1850.
    Abstract: Résumé La chasse courtoise dans le Duché de Westphalie à l'époque des princes-électeurs de la Maison des Wittelsbach (1583–1761) exigeait un grand nombre de chiens aux dispositions variées et dressés de façon polyvalente. Dans la mesure où la conduite en était assurée par le personnel de chasse de Westphalie, l'entretien de ces chiens était pris en charge par l'intendance du prince-électeur d'Arnsberg. Les frais s'élevaient à quelque 3000 «Reichstaler» par an. Lors de l'instauration de la pleine souveraineté, 90 fermes furent tenues d'héberger chacune un chien seigneurial à titre gratuit ou sinon de s'acquitter d'une redevance annuelle d'1 «Reichstaler». En dehors des fermiers, le bourreau et son valet de même qu'une série de couvents étaient appelés à assurer une pension aux chiens, laquelle était le plus souvent monnayée: les bourreaux payaient 64 «Reichstaler», les couvents 252 «Reichtstaler» par an. Une servitude cynégétique particulière était constituée par le prêt de chiens. Fermiers et bourgeois étaient arbitrairement contraints sous la menace de sanctions, de mettre leurs chiens, à titre gratuit et pour autant qu'ils conviennent à cet usage, à la disposition de chasses organisées par le prince-électeur ou par ses services. Les protestations qui s'élevèrent de-ci de-là contre cette servitude restèrent sans effet. Ce n'est que lors de la promulgation de la loi prussienne de remplacement de 1850 que cette servitude ainsi que toutes les autres charges liées à la chasse furent abolies.
    Notes: Zusammenfassung Die höfische Jagd im Herzogtum Westfalen in der Zeit der Kurfürsten aus dem Hause Wittelsbach (1583–1761) erforderte eine große Zahl vielseitig veranlagter und ausgebildeter Hunde. Soweit diese durch das Personal des westfälischen Jagdamtes geführt wurden, bestritt die kurfürstliche Oberkellnerei in Arnsberg ihren Unterhalt. Die Kosten beliefen sich auf etwa 3000 Rtlr (Reichstaler) im Jahr. Im Zuge der Ausbildung der vollen Landeshoheit wurde die Hundelege eingeführt, von der etwa 90 Bauernhöfe betroffen waren, die entweder je einen kurfürstlichen Herrenhund unentgeltlich aufzunehmen und zu versorgen oder statt dessen ein Hundegeld von 1 Rtlr im Jahr zu zahlen hatten. Außer Bauern waren auch die Scharfrichter und Büttel sowie eine Reihe von Klöstern zum Hundedienst verpflichtet, der freilich im allgemeinen durch Geldzahlungen abgelöst wurde. Die Scharfrichter zahlten 64 Rtlr, die Klöster 252 Rtlr im Jahr. Eine besondere Form des Hundedienstes war die Hundeleihe. Bauern und Bürger wurden willkürlich unter Androhung von Strafen gezwungen, ihre Hunde, sofern sie dazu geeignet waren, zu den vom Kurfürsten oder vom Jagdamt abgehaltenen Jagden unentgeltlich herzuleihen. Vereinzelt sich regender Widerstand gegen den Hundedienst führte zu keinem Erfolg. Er wurde erst zusammen mit allen übrigen Jagdlasten durch das preußische Ablösungsgesetz von 1850 aufgehoben.
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    European journal of wildlife research 29 (1983), S. 130-130 
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    European journal of wildlife research 29 (1983), S. 131-136 
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    European journal of wildlife research 29 (1983), S. 137-142 
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary The report deals with experiments on the beginning of reproductive capability of individually marked male and female fallow deer juveniles during the period 1979 to 1982. The animals lived as a juvenile group without any adults being present. The study revealed under the conditions of the experiment: 1.) male and female yearlings are as a general rule capable of reproduction at the age of 17 to 20 months; 2.) female yearlings who do not come into heat are weak individuals who are last in the line of priority, which is not pronounced in fallow deer; 3.) the reproduction activity takes place in the juvenile group without any obvious species-typical rutting behaviour; 4.) in 1 1/2 #x2013;2 1/2 year-old females, the reproductive period begins at the end of the 2nd third of November and lasts, as far as is known to date, until the end of the 2nd third of February. In a fallow deer group without adults there is no sharply limited rutting period: the reproductive period lasts at least 3 months; 5.) the late births to be seen again and again lie with the young females; 6.) 2–2 1/4 year-old females calving late require 2 further reproductive cycles until the calving time evens out at June; 7.) contrary to red deer, late calving fallow deer mothers can rear their calves successfully.
    Abstract: Résumé Sont présentées des recherches sur les débuts de l'activité de reproduction chez de jeunes daims mâles et femelles, marqués individuellement, au cours de la période 1979–1982. Les jeunes animaux vivaient entre eux en l'absence de sujets adultes. Dans les conditions de l'étude, les affirmations suivantes peuvent être avancées: 1. les yearlings mâles et femelles sont en état de se reproduire à partir de l'âge de 17 à 20 mois; 2. lorsque des yearlings femelles ne présentent pas d'oestrus, il s'agit de sujets faibles qui, dans la hiérarchie sociale — par ailleurs peu marquée chez le Daim-, occupent la dernière place; 3. l'activité génésique se déroule chez le groupe de juvéniles sans qu'apparaissent des comportements spécifiques du rut; 4. chez les femelles d'1 an 1/2 et de 2 ans 1/2, la période de reproduction débute à la fin de la 2ème décade de novembre et se poursuit, à notre connaissance, jusqu'à la fin de la 2ème décade de février; dans un groupe de daims sans sujets adultes il ne se présente pas de période de rut bien délimitée et la période de reproduction se prolonge pendant au moins 3 mois; 5. les mises bas tardives observées régulièrement chez le Daim sont à mettre au compte des femelles sub-adultes; 6. les femelles de 2 ans à 2 ans 1/4 aux mises bas tardives nécessitent 2 autres cycles de reproduction afin d'amener la période de mise bas à s'articuler autour du début juin; 7. contrairement au Cerf, les femelles du Daim dont la mise bas a été tardive sont à même d'élever leurs jeunes avec succès.
    Notes: Zusammenfassung Dargestellt werden Untersuchungen zum Beginn der Fortpflanzungsfähigkeit von individuell gekennzeichnetem jungem männlichem und weiblichem Damwild im Zeitraum von 1979 bis 1982. Die Tiere lebten als Jugendgruppe ohne Anwesenheit adulter Artgenossen. Die Studie ergab unter den Bedingungen des Versuches: 1.) weibliche und männliche Jährlinge sind im Alter von 17 bis 20 Monaten in der Regel fortpflanzungsfähig; 2.) wenn Jährlingsweibchen nicht in den Östrus kommen, handelt es sich um schwache Individuen, die in der beim Damwild an sich schwach ausgeprägten Rangordnung an letzter Stelle stehen; 3.) die Fortpflanzungsaktivität verläuft in der Jugendgruppe ohne deutlich erkennbare arttypische Brunftverhaltensweisen; 4.) bei 1 1/2- und 2 1/2 jährigen weiblichen Stücken beginnt die Fortpflanzungszeit am Ende des 2. Novemberdrittels und dauert, soweit bis jetzt bekannt, bis zum Ende des 2. Februardrittels. In einer Damwildgruppe ohne adulte Individuen gibt es keine zeitlich eng begrenzte Brunftperiode, die Fortpflanzungszeit dauert mindestens 3 Monate; 5.) die beim Damwild immer wieder beobachtbaren Spätgeburten gehen à conto der jungen weiblichen Stücke; 6.) spät setzende 2- bis 2 1/4 jährige Weibchen brauchen 2 weitere Fortpflanzungszyklen, bis die Setzzeit sich auf Juni eingependelt hat; 7.) im Gegensatz zu Rotwild können spätgebärende Damwildmütter ihre Kälber erfolgreich aufziehen.
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    Description / Table of Contents: Summary This paper deals with the occurrence of five species of the genus Anser on Helgoland in the years 1962 to 1982. The actual status of each species is determined and observations from former years are added. In general, observations of geese on Helgoland have been increasing during recent years. Taking together all observations of the species, Geese are more common in autumn than in spring. Most observations date from October. The numbers of Bean Geese(Anser fabalis) on passage have been increasing since 1970, the yearly totals fluctuating considerably. Migration time lasts from the end of September to mid March. The numbers of resting individuals have been increasing likewise. The Pink-footed Goose(Anser brachyrhynchus) has not been recorded every year. Increasing numbers of single individuals can be seen resting on Helgoland. The White-fronted Goose(Anser albifrons) is a scarce species on Helgoland, nevertheless appearing in increasing numbers both on passage and as a resting species. The Grey-lag Goose(Anser anser) is the most common species of the genus Anser. Since 1972 the species has been increasing considerably, nowadays being recorded annually on passage. Grey-lag Geese can be observed every month. A peak of migration occurs in September/October and February/March. In general, the flight distance of resting Grey-lag Geese is decreasing. The Snow-Goose(Anser caerulescens) has been recorded only once on Helgoland.
    Abstract: Résumé Cette contribution est consacrée à la dispersion de 5 espèces d'Anséridés sur l'île d'Helgoland de 1962 à 1982. En complément du statut d'une espèce d'oie on fait état des observations recueillies au cours d'années antérieures. Dans l'ensemble, les observations d'oies sur Helgoland ont augmenté au cours des dernières années. Les totaux révèlent cependant des observations plus massives lors de la migration d'automne, c'est-à-dire en octobre. L'oie des moissons(Anser fabalis) présente une fréquence d'observation croissante depuis 1970 tout en manifestant de fortes variations numériques. Cette oie est observée de fin septembre jusqu'à mi-mars. Le stationnement de cette espèce sur Helgoland est également en augmentation depuis les dernières années. L'oie à bec court(Anser brachyrhynchus) n'est pas observée chaque année. Des individus isolés sont cependant observés de plus en plus fréquemment sur Helgoland. L'oie rieuse(Anser albifrons) s'observe rarement sur Helgoland. Toutefois, tant le passage migratoire que le stationnement de l'espèce montre une tendance à l'accroissement au cours des dernières années. L'oie cendrée(Anser anser) est l'espèce la plus fréquemment observée. Depuis 1972, l'accroissement de l'espèce est net et son passage migratoire s'observe tout au long de l'année avec une pointe en septembre-octobre et en février-mars. D'une façon générale, la distance de fuite des oies qui stationnent sur Helgoland diminue. L'oie des neiges(Anser caerulescens) n'a pu être observée qu'une seule fois sur l'île.
    Notes: Zusammenfassung In dieser Arbeit wird das Vorkommen von fünf Anser-Arten auf Helgoland von 1962–1982 beschrieben. Ergänzend zur Festlegung des Status einer Gänseart werden Beobachtungen früherer Jahre erwähnt. Allgemein haben die Gänsebeobachtungen auf Helgoland in den letzten Jahren zugenommen. In der Gesamtsumme aller Gänsebeobachtungen tritt der Herbstzug deutlicher in Erscheinung als der Frühjahrszug. Die meisten Gänsebeobachtungen fallen in den Oktober. Die Saatgans wird seit 1970 zunehmend beobachtet, schwankt aber stark in ihrem Vorkommen. Saatgänse werden von Ende September bis Mitte März auf Helgoland festgestellt. Das Rastvorkommen der Saatgans auf Helgoland steigt ebenfalls in den letzten Jahren. Die Kurzschnabelgans wird nicht alljährlich beobachtet. Einzeltiere werden zunehmend rastend auf Helgoland angetroffen. Die Bläßgans ist auf Helgoland selten. Sowohl das Zug- als auch das Rastvorkommen zeigt in den letzten Jahren allerdings eine zunehmende Tendenz. Die Graugans ist die am häufigsten beobachtete Anser-Art. Ab 1972 nimmt die Art deutlich zu. Die Graugans ist heute alljährlicher Durchzügler. Ihr Vorkommen verteilt sich über das ganze Jahr. Ein Zugmaximum liegt im September/Oktober und Februar/März.
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    European journal of wildlife research 29 (1983), S. 197-213 
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    European journal of wildlife research 29 (1983), S. 244-247 
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary On individually marked fallow dear stags (Dama dama L.), the activity of the alkaline phosphatase (AP) in the serum was examined from throwing of the spikes over 2½ years with 3 another cycles. It was thereby demonstrated that 1) the activity of the AP shows an obvious course over the periods of the year, 2) the peaks of activity over the periods of the year are clearly correlated with the 3 phases of antler formation, and 3) the level of maximum activity is related to the throwing weight of the antlers.
    Abstract: Résumé L'activité dans le sérum de la phosphatase alcaline (AP) depuis le rejet des dagues et tout au long des 2,5 années qui y ont fait suite (recouvrant 3 cycles de développement des bois) a été étudiée sur des daims (Dama dama L.) marqués individuellement. Il apparaît que (1) l'activité de l'AP présente un déroulement circannien caractérisé, (2) que les maxima annuels d'activité sont en corrélation avec les trois périodes de refait des bois et (3) que l'amplitude des variations est liée aux poids des mues.
    Notes: Zusammenfassung An individuell gekennzeichneten Damhirschen (Dama dama L.) wurde die Aktivität der Alkalischen Phosphatase (AP) im Serum vom Abwerfen der Spieße an über 2,5 Jahre hinweg mit 3 Geweihzyklen untersucht. Dabei zeigte sich, daß 1. die Aktivität der AP einen ausgeprägten jahresperiodischen Verlauf aufweist, 2. die jahresperiodischen Gipfel ihrer Aktivität deutlich mit den 3 Geweihbildungsphasen korrelieren und 3. die Höhe der Aktivitätsmaxima in Beziehung steht zum Abwurfgewicht der Geweihe.
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    European journal of wildlife research 29 (1983), S. 235-243 
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    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary This report from the Forest Office Brilon, formerly Forest Office Bredelar, in the Sauerland, describes experiments on the effect of intense side-shoot gnawing in spruce on the growth of the spruce. The study covered the period 1968 to 1976. Six experiments were set up. In fenced enclosures of in each case roughly 450 m2 (fig. 1), measurements were made annually of the height of up to 16 plants. By way of comparison, up to 32 plants with intense gnawing of side shoots were measured (fig. 2). The results of the height measurements are shown in tables 1 to 6. The extent of the side-shoot gnawing in each case recorded. In all cases there was for at least 1 and for up to 8 years a significant difference between the length of growth on the plants inside the fence and outside the fence. It must therefore be drawn from this that intense gnawing of side-shoots, as was present in the research plot', leads to a reduction of growth. No answer can be given to the question of whether the reduction in growth balances out in later years. The superior growth on the shoots outside the fence for the experiments shown in tables 1 and 2 indicates that such a balancing is possible. The burdens which emerged during the experiment as a result of side-shoot gnawing are an indication of the fact that the roe-deer population was too high, i.e. that it was not supportable.
    Abstract: Résumé Il est rendu compte de recherches exécutées dans l'ancien cantonnement forestier de Brilon, dans le Sauerland (Rhénanie-Westphalie), sur les effets d'un abroutissement intense des pousses latérales sur la croissance en hauteur de l'Epicéa. Les observations se déroulèrent entre 1968 et 1976. Six dispositifs ont été installés. Dans une clôture mesurant chaque fois quelque 450 m2 de superficie (Fig. 1) la longueur des pousses terminales a été mesurée sur pas moins de 16 plants et, à titre comparatif, des mesures furent effectuées sur 32 plants qui subissaient des abroutissements prononcés des pousses latérales. Le résultat de ces mesures est présenté dans les Tableaux 1 à 6. L'intensité de l'abroutissement des pousses latérales est mentionnée à chaque reprise. Dans tous les dispositifs apparaît une différence significative — pendant une à huit années au moins — entre la hauteur des pousses terminales des plants situés sous et hors-clôture. Il en résulte qu'un abroutissement des pousses latérales, tel qu'il a été provoqué dans le cadre de ces essais, entraîne une diminution de la croissance en hauteur. La question de savoir si ce retard de croissance est récupéré par la suite reste ouverte. L'accroissement supérieur des pousses terminales à l'extérieur de la clôture pour les essais renseignés dans les Tableaux 1 et 2 semble indiquer qu'un tel rattrapage est possible. Les charges qui se sont manifestées au cours des essais par suite de l'abroutissement latéral constituent un indice comme quoi la densité de population de chevreuils était excessive et donc intolérable.
    Notes: Zusammenfassung Aus dem ehemaligen Forstamt Bredelar, heute Forstamt Brilon, im Sauerland in Nordrhein-Westfalen werden Versuche zur Auswirkung eines starken Seitentriebverbisses an Fichte auf das Höhenwachstum der Fichte dargestellt. Die Beobachtungen erstreckten sich über den Zeitraum von 1968 bis 1976. Sechs Versuche wurden angelegt. In einem Gatter von jeweils rund 450 m2 Größe (Abb. 1) erfolgten jährlich Messungen der Höhentriebe an bis zu 16 Pflanzen, zum Vergleich wurden bis zu 32 Pflanzen, die starken Seitentriebverbiß aufwiesen, vermessen (Abb. 2). Das Ergebnis der Höhentriebmessungen ist in den Tabellen 1 bis 6 dargestellt. Der Umfang des Seitentriebverbisses wird jeweils vermerkt. In allen Fällen trat für mindestens 1 und bis zu 8 Jahre ein signifikanter Unterschied der Länge der Höhentriebe für die Pflanzen im Gatter und außerhalb des Gatters auf. Gefolgert werden muß, daß starker Seitentriebverbiß, wie er bei der Versuchsanlage vorhanden war, zu einer Minderung des Höhenwachstums führt. Nicht beantwortet werden kann die Frage, ob die aufgetretene Verminderung des Höhenwachstums in späteren Jahren ausgeglichen wird. Das überlegene Wachstum der Höhentriebe außerhalb des Gatters für die in den Tabellen 1 und 2 nachgewiesenen Versuche spricht dafür, daß ein derartiger Ausgleich möglich ist. Die während des Versuches eingetretenen Belastungen durch Seitentriebverbiß sind ein Weiser dafür, daß der Rehwildbestand überhöht, d. h. auch nicht tragbar war.
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    Mathematical programming 19 (1980), S. 300-312 
    ISSN: 1436-4646
    Keywords: Equilibrium Prices ; Nonconvex Mathematical Programming ; Shadow Prices
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract In this paper a definition is proposed for the concept of shadow prices in nonconvex programming. For a nonlinear program with equality and inequality constraints, existence of these prices and bounds for their possible values are obtained under the Mangasarian—Fromowitz regularity condition. Their exact values and some continuity properties are obtained under the more restrictive linear independence regularity condition. A definition of equilibrium prices is also proposed. Under convexity assumptions, all definitions and results coincide with those already known on this subject in convex programming.
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  • 198
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    Mathematical programming 19 (1980), S. 313-327 
    ISSN: 1436-4646
    Keywords: Retrogressing Paths ; Homotopy Method ; Fixed-point Algorithm
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract For certain functionsf fromR n toR n , the Eaves—Saigal algorithm computes a path inR n × (0, 1] which converges to a zero off. In this case, it is shown that even whenf is of classC ∞ and has a unique zero, the converging path may retrogress infinitely many times.
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  • 199
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    Mathematical programming 18 (1980), S. 186-196 
    ISSN: 1436-4646
    Keywords: Weber's Problem ; Weiszfeld's Method ; Optimal Location
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract For solving the Euclidean distance Weber problem Weiszfeld proposed an iterative method. This method can also be applied to generalized Weber problems in Banach spaces. Examples for generalized Weber problems are: minimal surfaces with obstacles, Fermat's principle in geometrical optics and brachistochrones with obstacles.
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  • 200
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    Mathematical programming 18 (1980), S. 84-88 
    ISSN: 1436-4646
    Keywords: Complementary Pivot Algorithms ; Triangulations ; Vector Labels ; Borsuk's Theorem on Antipodal Points
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract In this short note a simple and constructive proof is given for Borsuk's theorem on antipodal points. This is done through a special application of the complementary pivoting algorithm.
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