ALBERT

Notizen: Abstract In the theory of organismic sets (Bull. Math. Biophysics,31, 159–198, 1969) we considered organisms as sets endowed with certain “activities,” the latter’s resulting in a set of “products.” Those products may be of a material nature, like a hormone secreted by a cell, or of a non-material nature, like a feeling or an attitude. In the present paper aggressiveness and submissiveness are considered as such non-material products of the activities of the brain cells. A general description of aggressiveness and submissiveness is given in terms of organismic sets. Cycles in “peck order” are thus naturally explained.

Notizen: Abstract In line with previous studies on organismic sets, the division of all organismic sets intogeneral autotrophic and heterotrophic is introduced. The first produce their food themselves from some external source of energy, which in general may be an energy of any kind. The others use other organismic sets as the source of their food and energy. On earth we know only one kind of generalgeneral autotrophic organismic sets, namely, the autotrophic plants which use solar radiation as their source of energy and for production of their own food. It is shown why autotrophic animals do not exist on earth except as microorganisms like, e.g.,Euglena. A rigorous proof of the previously derived theorem that in an organismic set of ordern〉1 no element can be completely specialized is given. It requires the introduction of new postulates. Finally, in considering the organic world as a whole, the notion of organismic sets ofmixed order is introduced.

Notizen: Abstract It appears to be axiomatic that termolecular and higher order reactions occur relatively rarely. The basis for this judgment seems to lie in the supposition that successful 3-Body collisions of 3 interactive species of molecules cannot occur frequently enought to account for chemical or biochemical transformation. In order to provide a more complete mathematical framework than now exists for examining this hypothesis the probability of effective termolecular “δ-collisions” as a function of time is derived. This amounts to adding to the class of reactions for which stochastic models are now available the termolecular reaction. In common with the unimolecular and bimolecular cases this process is seen to satisfy the criterion of consistency-in-the-mean with respect to deterministic formulations. It is planned next to use the termolecular process and the lower order processes in computer-assistedin numero experimental studies aimed at comparing alternative mechanisms of reaction.

Notizen: Abstract Small sample properties of the maximum likelihood estimator for the rate constant of a stochastic first order reaction are investigated. The approximate bias and variance of the maximum likelihood estimator are derived and tabulated. If observations of the system are made at timesiτ,i=1, 2, ...,N; τ〉0, the observational spacing τ which minimizes the approximate variance of the maximum likelihood estimator is found. The non-applicability of large sample theory to confidence interval derivation is demonstrated by examination of the relative likelihood. Bartlett’s method is employed to derive approximate confidence limits, and is illustrated by using simulated kinetic runs.

Notizen: Abstract The representation of biological systems by means of organismic supercategories, developed in previous papers (Bull. Math. Biophysics,30, 625–636;31, 59–71;32, 539–561), is further discussed. The different approaches to relational biology, developed by Rashevsky, Rosen and by Băianu and Marinescu, are compared with Qualitative Dynamics of Systems which was initiated by Henri Poincaré (1881). On the basis of this comparison some concrete result concerning dynamics of genetic system, development, fertilization, regeneration, analogies, and oncogenesis are derived.

Notizen: Abstract Some years ago (Rosen 1958a, b; 1959) we described a class of metaphorical, relational paradigms for cellular activity which we termed (M, R)-systems. A sizable amount of subsequent work, to be itemized below, has been devoted to an exploration of some of the properties of these systems. The main purpose of the present paper is to put this class of paradigms into a general system-theoretic perspective, with a particular view to appraising the relation between the type of system description embodied in the (M, R)-system and other kinds of physical and mathematical descriptions of cellular systems. Thus, the principal aim is to establish the relationships and connections between the global relational formalism embodied in the (M, R)-systems and the empirical descriptions which still represent the bulk of our biological knowledge.

Notizen: Abstract After giving a brief review of the theory of organismic sets (Bull. Math. Biophysics,29, 139–152, 1967;31, 159–198, 1969), in which the concept of relational forces, introduced earlier (Bull. Math. Biophysics,28, 283–308, 1966a) plays a fundamental role, the author discusses examples of possible different structures produced by relational forces. For biological organisms the different structures found theoretically are in general agreement with observation. For societies, which are also organismic sets as discussed in the above references, the structures can be described only in an abstract space, the nature of which is discussed. Different isomorphisms between anatomical structures, as described in ordinary Euclidean space, and the sociological structures described in an abstract space are noted, as should be expected from the theory of organismic sets.

Notizen: Abstract Current psychological research into the inference (diagnostic) process is briefly reviewed, using as a vehicle an investigation of the prediction of the probability of success of hypothetical applicants to a graduate program in biology. Brunswik’s lens model and multiple regression analysis are used, as is a Bayesian approach. Four judges’ (biologists’) predictions are analyzed. Some general conclusions about inference, drawn from the current data in psychology, are presented.

Notizen: Abstract A mathematical model has been developed to simulate the glucose-insulin interaction following a glucose load such as occurs in an IVGTT. This model differs from earlier models in that the insulin response to glucose loading is a recurring all or none threshold response. The model has been simulated on a digital computer using the digital analog simulation language CSMP.

Notizen: Abstract The composite nature of bone dictates the use of a model for bone which is transversely isotropic. We solve the associated sets of partial differential equations governing the dynamic elastic behavoor of a two-layered cylindrical-shaped bone. The solution is analyzed for long, short, and intermediate length waves. The special case of compact bone is treated for long and short wave lengths and a numerical example is worked out to determine the wave speeds (for short wave lengths) given a set of elastic constants, determined by ultrasonic methods, and the bone density, wave frequency, and radius.

Notizen: Abstract A stochastic model is developed for an enzyme reaction in an open linear system. The proposed model assumes that the open system maintains the concentration of substrate and inhibitor at constant levels and that the product molecules are removed from the system by a first order reaction. Stochastic models for several enzyme reactions occurring in this open system are shown to correspond to special cases of theGI/M/∞ queue. Takács’ (1958) results for this queueing system are used to obtain the stochastic properties of the enzyme systems. A specific model we studied assumed completely competitive inhibition in an open system. The stationary distribution for the number of product molecules in the system is obtained. The enzyme reaction which incorporated the “intermediate chain hypothesis” can also be investigated by the queueing theory approach. It is shown that for this open system, if the model which incorporated the intermediate chain hypothesis has the same deterministic properties as the Michaelis-Menten model, then the latter has greater stochastic variation than the former.

Notizen: Abstract The existing methods to solve the problems of pulsatile flow in the cardiovascular system are based on either linear axisymmetric equations or non-linear one-dimensional equations. The solutions thus obtained give only a mediocre comparison with measurements. In this paper, a non-linear axisymmetric theory is proposed. The starting point of the present theory is a third degree polynomial representation of the velocity profile. Integral methods are then applied to obtain the governing equations. To ascertain the accuracy of the theory proposed above, the calculations for a simple case involving pulsatile flow in a long rigid tube were performed. The results are: (a) the average velocities compare very well with exact solutions and (b) the velocity profiles for a given frequency agree very well with exact solutions for flow in small tubes, but tend to differ as tube size is increased.

Notizen: Résumé Le but de ce travail est la mise en évidence d’éventuels “patterns” temporels privilégiés de potentiels d’action neuronaux masqués par la superposition d’une activité aléatoire. Dans la première partie, on propose un modèle susceptible de rendre compte de cette activité aléatoire. Dans la seconde, on expose une méthode d’extraction des patterns privilégiés, compatible avec les paramètres du modèle neuronal proposé. Son algorithme fait notamment intervenir l’estimation de la fonction d’expectation. Cette méthode peut, en fait, ment intervenir l’estimation de la fonction d’expectation. Cette méthode peut, en fait, être appliquée à l’étude de séries temporelles d’événements dans des domaines très divers.

Notizen: Abstract An effort is made to begin widening the scope of kinetics by merging the concepts and point of view of molecular set theory with the stochastic approach to kinetics, beginning with the simplest unimolecular molecular set transformation. In this spirit the new concept ofmolecular set variable is introduced as the basic unit of kinetics as opposed to simply the traditionalconcentration (or cardinality) unit, connoting that the composition as well as the size of a molecular set are significant dynamic features of a system. The changes in state (or “value”) of the molecular set variable are characterized by a Markovian stochastic process and the relationship between this process and the corresponding unimolecular process for the concentration variable introduced earlier is discussed. The possible role of molecular set theory in terms of the underlying biomathematical structure of relational biology is also considered.

Notizen: Abstract The problem of the forms of plants and models of branching are discussed using experimental data on the mistletoe. The number of branches by division, the distribution of divisions with regard to the number of branches per division and to the level of division, the geometrical characters of branches according to the level of division and the host, the stability of model are studied. One gives an interpretation of the model of branching as a model of growth.

Notizen: Abstract A quantum model for the general enzymic reaction,E+S ⇌ ES → P, is presented, starting with the assumptions that any chemical substanceS, which may be a substrate for a particularE (S)-enzyme is a microphysical system and any enzymeE-molecule, capable of interacting with anS-substrate is a “measuring system” which will “measure” one or more of theS-observables. According to the above assumptions a stochastic model of the reaction is constructed and a computer simulation of the steady state performed. The results thus obtained predicted fluctuations in the enzymic reaction rate, function of the substrate “perturbation”. On an experimental basis it is demonstrated that the irradiation of an enzymic substrate with low energies results in the inducement of a dose-dependent oscillatory behavior in the corresponding enzymic reaction rate. In the reaction type, the oscillations thus induced in theE-activity by the corresponding substrates are out-of-phase, realizing a biochemical discriminating net. Likewise, in an $$S_1 \xleftarrow{{E_1 }}S\xrightarrow{{E_2 }}S_2$$ reaction type, the oscillations induced by the irradiatedS-substrate in the activities of the respective enzyme, realize a biochemical switching net.

Notizen: Abstract This paper is the second of a pair dealing with some mathematical properties of metabolic steady state. An investigator wishing to compute the rate of appearance and/or disappearance of a metabolite in steady state within an intact biological system will usually appeal to a method involving radioactive tracers. It is shown that while the investigator’s choice of the mode of tracer administration (constant infusion or single injection) is largely arbitrary, the mathematical interpretation of the results may depend upon the presence or absence of gradients in certain of the variables of the system. The latter will be the case if the system is sampled at a point within the distribution space of the metabolite which is not a source point but is otherwise arbitrary. In order to deduce a formula which gives the required rate, he must have knowledge of the gradient of concentration of the traced substance, and sometimes of the gradient of specific activity.

Notizen: Abstract Making a medical diagnosis consists of correlating knownpatterns of disease with the various classes of clinical data elicited from the history, physical examination, and batteries of tests relative to the diagnostic dynamics symbolized by atree branching into the various possible diagnostic decisions. In this paper a relational mathematical model of the reasoning aspects of the conventional medical diagnostic process is suggested as a way of extracting a general, formal concept of medical diagnosis. Computer implementation of the model is discussed briefly.

Notizen: Abstract Biomedical data in the form of series of observations made on a single process at regular intervals constitute a discrete time series and are eligible for time series methods of analysis. The models yielded by this analysis provide the framework within which exponential smoothing methods may operate on the data to provide recurrent forecasts of future states of the process. Because the forecasts may be made on an individual basis and are sensitive to the past behavior of the individual process, the methods are presented as being potentially of great utility in the management of chronic and progressive illnesses. When incorporated into automated testing and diagnostic systems, the forecasting method will provide the capability of making prognoses for large numbers of individuals, quickly, routinely and reproducibly.

Notizen: Abstract Chorioretinal temperature increases produced by solar observations are computed digitally. The spectral characteristics of solar radiation and the spectral transmittances of the atmosphere, atmospheric water vapor and ocular media are considered. Image spread is employed in all calculations. The calculations are executed for a variety of observation angles, and the effects of pupil diameter, fixed filters and optical instruments are predicted. Temperature increases are also computed for solar eclipse observations by the appropriate superposition of unobscured solar disk solutions.

Notizen: Abstract The diffusion equation according to Fick’s law is solved for a spherical cell, surrounded by an infinite medium with different diffusion properties. The method of Laplace transform is used to obtain the formal solution, however, no inversion can be found for all times and an expansion suitable for small times is performed. The final expression found is expanded further to be more suited for the determination of the diffusion coefficient from an experimental curve. Application to a biological problem is dissussed.

Notizen: Abstract A simple mathematical model of first and second degree heart block is developed on the assumption that eachR wave, with its associated ventricular contraction, results in the release of a substance which raises the excitation threshold of the conducting tissue lying between theS-A andA-V nodes. The conduction pathway is represented by a chain of excitatory elements, the first member of which is acted upon by a regularly occurringP wave. The rate constant of the removal of this inhibitory substance, i.e., recovery rate, is the only constant necessary to be varied in order to pass from normal to first degree block to second degree. In this latter case one can predict the progressive increase inP-R interval until anR wave is missed, as occurs in the Wenckebach phenomenon. The model indicates that an increasedP wave frequency which would have little effect on theP-R inerval for a normal individual with rapid recovery, could produce a Wenckebach pattern in an individual with even a mild first degree block.

Notizen: Abstract The temperature dependence of the Elovich equation, which is−dx/dt=m exp (nx) (wherex is concentration of substrate or ion,t is time, andm andn are coefficients dependent upon temperature), has been derived from the hypothesis of electron or ion conduction across an activation energy barrier at the surface of a biological particle or membrane, driven by a difference in redox or ion potentials. Using the additional hypothesis of reversible, temperature-dependent, inactivation of sites of reduction or complexing, the theory predicts that both coefficientsm andn have linear Arrhenius plots, in agreement with experimental data for gas adsorption on inorganic solid surfaces, and with two studies of muscle spindle adaptation.

Notizen: Abstract The discussion will center mainly on some work on two solution concepts: the core for gaines without side payments and the nucleolus for games with side payments (characteristic funtion games). The core has become an important equilibrium concept in mathematical economics. The nucleolus is related to the theory of bargaining sets.

Notizen: Abstract We consider a quadratic program equivalent to the general problem of minimizing a convex quadratic function of many variables subject to linear inequality constraints. In previous work [12], one of us presented an algorithm related to such problems, and classified them under “combinatorial equivalence”. The classification contained linear programs at one end (where the function has zero quadratic part) and least-distance programs at the other. A least-distance program is a problem of finding a point of a convex polyhedron which is at least distance from a given point; such programs have been studied by one of us [15, 17] and were shown to correspond to that case of the general problem where the function has positive definite quadratic part. We now extend the work on least-distance programs to those programs intermediate between linear and least-distance (called “essentially bisymmetric” in [12]), and show that such programs are really “hybrids”, with traits inherited from both parent programs: linear and leastdistance.

Notizen: Abstract An algorithm is given for solving the optimum potential problem, which is the dual of the classical “out-of-kilter” algorithm for flow problems. Moreover, a new proof of finiteness is provided, which holds even for non-rational data; it applies to all the algorithms of network theory which include a labeling process.

Notizen: Abstract Using a fixed point theorem of Browder, the basic existence theorem of Lemke in linear complementarity theory is generalized to the nonlinear case.

Notizen: Abstract Linear-algebra rank is the solution to an especially tractable optimization problem. This tractability is viewed abstractly, and extended to certain more general optimization problems which are linear programs relative to certain derived polyhedra.

Notizen: Abstract The relative merits of using sequential unconstrained methods for solving: minimizef(x) subject tog i (x) ⩾ 0, i = 1, ⋯, m, h j (x) = 0, j = 1, ⋯, p versus methods which handle the constraints directly are explored. Nonlinearly constrained problems are emphasized. Both classes of methods are analyzed as to parameter selection requirements, convergence to first and second-order Kuhn-Tucker Points, rate of convergence, matrix conditioning problems and computations required.

Notizen: Abstract Consider the problem of finding the minimum value of a scalar objective function whose arguments are theN components of 2 N vector elements partially ordered as a Boolean lattice. If the function is strictly decreasing along any shortest path from the minimum point to its logical complement, then the minimum can be located precisely after sequential measurement of the objective function atN + 1 points. This result suggests a new line of research on discrete optimization problems.

Notizen: Zusammenfassung In der vorliegenden Arbeit werden Lösungen der DifferentialgleichungF (z,z *)w zz *−n(n+1)w=0 mit $$F(z,z * ) = \frac{{[\varphi (z) + \psi (z * )]^2 }}{{\psi '(z)\psi '(z * )}}$$ mit Hilfe von Integraloperatoren betrachtet. Durch geeignete Wahl der Erzeugenden (Kern des Integraloperators) können die dadurch gewonnenen Lösungen integralfrei dargestellt werden. Damit werden auch die Zusammenhänge zu der vonK. W. Bauer in [1] und [2] verwendeten Darstellung der Lösungen mittels Differentialoperatoren aufgezeigt.

Notizen: Summary Nine healthy young volunteers received diets furnishing from 5 to 10 eggs (1.03–2.06g egg cholesterol) per day through two consecutive periods of 3 weeks. The amounts of proteins and fat per 100 calories were the same in all the diets. Immediately before, and 3 and 6 weeks after beginning of the egg regimen, samples of duodenal bile were collected, after injection of cholecystokinin, and analyzed with respect to pH, dry matter, cholesterol, lipid-soluble phosphorus, glycocholic acid, glycochenodeoxycholic acid, glycodeoxycholid acid, taurocholic acid and taurochenodeoxycholic plus taurodeoxycholic acids. Simultaneously with the collection of bile, blood samples were taken for determination of serum total cholesterol. The main results were as follows: Serum total cholesterol increased during the egg regimen. In the bile no great changes occurred in the distribution of the different bile acids in the total bile acids. The predominant change of the ratios between total bile acids and cholesterol and between lipid-soluble phosphorus and cholesterol was a slight to moderate increase. Thus, the results did not provide evidence for a lessening of the solubility of cholesterol in the bile in spite of the fact that serum cholesterol increased.

Notizen: Summary With the further purpose of studying the influence of diet and pharmaca on human bile, the composition of duodenal bile from 42 healthy young volunteers (group V, 7 men, 35 women) was compared with the composition of bladder bile from 27 peptic ulcer patients without diseases of the biliary tract and liver (group A, 17 men, 10 women), and with the composition of bladder bile from 26 patients having uncomplicated gallstone disease and functioning gall bladder (group B, 4 men, 22 women). Generally, the duodenal biles had lower concentrations of the components determined (dry matter, cholesterol, lipid-soluble phosphorus and bile acids) than had the bladder biles, especially those in group A. The mean value of the molar ratio between glycine-conjugation and taurine-conjugation was somewhat lower in group V than in groups A and B. The mean value of the ratio between total bile acids and lipid-soluble phosphorus was almost the same in groups V and A, and higher than in group B. Comparison of the individual values of the ratio between lipid-soluble phosphorus and cholesterol with yet unpublished studies of the solubility of cholesterol in aqueous solutions of lecithins and bile salts suggests that roughly half of the biles in all three groups would be supersaturated with respect to cholesterol if the solubility of cholesterol in bile depends only on the components determined in the present study. The fatty acid composition of bile lecithin was determined in 23 cases from group V, 16 cases from group A and 13 cases from group B. The distribution of the fatty acids was almost the same in groups A and B as in 17 cases in group V, in which less than 10% lysolecithin was formed during collection of the bile samples.

Notizen: Summary Seven healthy young volunteers received daily doses of cholestyramine (ca. 0.4 g „Cuemid“ per kg body weight) through two consecutive periods of 3 weeks. Duodenal bile was collected, after injection of cholecystokinin, twice before and 3 and 6 weeks after beginning of the treatment. The bile samples were analyzed with respect to pH, dry matter, cholesterol, lipid-soluble phosphorus, glycocholic acid, glycochenodeoxycholic acid, glycodeoxycholic acid, taurocholic acid and taurochenodeoxycholic plus taurodeoxycholic acids. Simultaneously with the collection of bile, blood samples were taken for determination of serum total cholesterol. Compared with the respective mean values before beginning of the treatment, the predominant changes were as follows: Serum total cholesterol decreased. In the bile, the molar ratio between dihydroxycholanoic acids, and trihydroxycholanoic acids decreased markedly, and the molar ratio between glycine-conjugation and taurine-conjugation increased. These changes were due to drastic increase of the molar percentage of glycocholic acid and more or less pronounced decreases of the molar percentages of the other bile acids in the total bile acids. The mean values of the molar ratios between total bile acids and cholesterol and between lipid-soluble phosphorus and cholesterol were slightly to moderately decreased. Thus, the results have not provided evidence for an increased solubility of cholesterol in the bile as a consequence of cholestyramine treatment, but rather point in the opposite direction, although further data are necessary before a decisive conclusion can be reached.

Notizen: Summary Recently,Weihofen andPringle compared, by means of „Z-scores“, the heights and weights of 36 children with cystic fibrosis with the heights and weights of 30 „normal“ children, finding that indeed the sick children were both significantly shorter and significantly lighter than healthy ones. However, it would be expected that this be the case, and for that reason, we ask and answer, by means of multivariate statistical theory, whether the height-weight growth in normal children has been not just retarded, but distorted. That is, if growth has been retarded, as could be the case with any ill child regardless of the illness, he could possibly recover what he has lost more readily if his growth is uniformly retarded, as a prematurely born infant can reach full height-weight proportions. Of course, we define mathematically exactly what we mean by the term „distortion“. Next, we correct several calculation errors ofWeihofen andPringle and point out the necessity of publishing the raw data. That is, we wrote Mrs.Weihofen for the original data for normal children and were told that she „must have discarded“ it. Since not all data is available, it cannot be reviewed for accuracy, and we must make an approximation, which we explain, in order to apply our multivariate statistical procedure. However, we do not feel that the approximation will seriously affect the results, and, in any case, it affords an opportunity to demonstrate the method.

Notizen: Zusammenfassung Eine Analyse des Zuckerverbrauchs in der BRD und der CSSR zeigt, daß der Unterschied im Verbrauch von etwa 6 kg je Kopf und Jahr auf den Verbrauch in Haushalten — Zuckereinkauf — zurückzuführen ist. Das geht aus Versorgungsangaben und Daten der Wirtschaftsrechnungen hervor. An zuckerreichen Erzeugnissen wird in der BRD nur ein höherer Verbrauch an Schokolade und Süßwaren festgestellt. Der ernährungsphysiologische Aspekt ist für die Beurteilung des Verbrauchs konsequent zu verfolgen. Ein hoher Zuckerverbrauch hat eine negative Auswirkung auf die gegenwärtig erwünschte Ernährung. Sie zeigt sich besonders in dem als Folge eines höheren Zuckerverbrauchs bedingten reduzierten Verbrauch an biologisch wertvolleren Lebensmitteln. Die Preise von Zucker und zuckerreichen Erzeugnissen sind in der BRD niedriger und können nicht eine Hemmung der Steigerung des Zuckerverbrauchs bedeuten, ebenso wie die relativ, im Vergleich mit anderen Positionen des Nahrungsmittelverbrauchs, langsame Erhöhung des Zuckerpreises. Demgegenüber kann die Preisentwicklung in der CSSR als einer der Faktoren des steigenden Zuckerverbrauchs bezeichnet werden. Beschriebene Unterschiede im Verbrauch finden einen Rückschlag im Nährwertgehalt des Lebensmittelverbrauchs, in seiner Zusammensetzung sowie in den Nahrungsmittelausgaben. Die Erzeugungsverhältnisse zeigen in der BRD einen dem Verbrauch in etwa angepaßten Zuckerrübenanbau, in der CSSR aber eine weniger intensive Übererzeugung, welche fast zur Hälfte für die Ausfuhr bestimmt ist. In beiden Ländern erhöht sich die Zuckererzeugung, in der CSSR ein wenig schneller, ebenfalls die Erzeugung an zuckerreichen Erzeugnissen. Was den Zuckergehalt in den Erzeugnissen betrifft, scheint dieser in der BRD außer in Getränken prinzipiell höher zu sein. An weiteren, den Zuckerverbrauch beeinflussenden Faktoren sind bisher weniger bekannte oder beachtete Ernährungsgewohnheiten zu erwähnen, die aber von der Volkswirtschaft unmittelbar oder mittelbar beeinflußt werden. In der ernährungsphysiologischen Beurteilung positive Tätigkeiten von Gesellschaften und Institutionen in bezug auf Aufklärung, wirtschaftspolitische Maßnahmen, können in dem Zusammenhang ebenfalls genannt werden. Die Situation des Zuckerverbrauchs in beiden Ländern läßt sich dahingehend charakterisieren, daß die Trends des Verbrauchs und der Erzeugung steigend sind, die jedoch zugleich eine Tendenz zu einer gewissen Verschlechterung der gesamten Ernährungssituation bedeuten. Unsere Analyse sucht Begründungen für die Unterschiede der Verbrauchshöhen beider Länder. In der BRD wurden keine Ursachen außer dem des Verbraucherverhalten gefunden. In der CSSR lassen sich dagegen einige Momente in der Wirtschaftspolitik zeigen, die für die Steigerung des Zuckerverbrauchs eine günstige Ausgangsposition bildeten. Trotz der Unterschiede sind in beiden Ländern Überlegungen zur weiteren Entwicklung aktuell, wozu diese Studie Unterlagen bringen kann. In der BRD kann die volle Aufmerksamkeit der industriellen Verarbeitung gewidmet werden, wo Möglichkeiten zur Beschränkung des Zuckeranteils zu suchen sind. In der CSSR liegt der Schwerpunkt in den Privathaushalten, also im Wirken auf die Verbraucher und in der Getränkeherstellung.

Notizen: Zusammenfassung Die Versuche ergaben, daß die Verfütterung erhitzter Öle an Wistar-Ratten keinen Einfluß auf die Fortpflanzung der Versuchstiere und die Aufzucht von deren Jungen hat. Junge Weibchen zeigten sich signifikant paarungsfreudiger als ältere.

Notizen: Summary The solubility of cholesterol in aqueous solutions of bile salts and lecithin with N/10 phosphate buffer, pH 7.3 has been examined. For the sodium salts of the six bile acids used in the study, the capacity for dissolving cholesterol was found to decrease in the following order: Glycodeoxycholate, Taurodeoxycholate, Glycochenodeoxycholate, Taurochenodeoxycholate, Glycocholate, Taurocholate. The differences with respect to cholesterol dissolving capacity were greatest when no lecithin was present, and decreased as the amount of lecithin increased. Graphical representations (molar ratio bile salt to cholesterol as abscissa, molar ratio lecithin to cholesterol as ordinate) of the limits for solubility of cholesterol in 100 millimolar solutions of each of the six bile salts to which purified egg lecithin is added in amounts varying from zero to approximately 80 millimoles per 100 millimoles bile salt, had the shape of curved lines tending to converge against a point, approximately 3.5, on the vertical axis but without reaching it. (Fig. 1). The starting points of the curves on the horizontal axis (millimoles bile salt required to dissolve 1 millimole of cholesterol in the absence of lecithin) were: for Glycodeoxycholate 19, for Taurodeoxycholate 30, for Glycochenodeoxycholate 34, for Taurochenodeoxycholate 47, for Glycocholate 52, for Taurocholate 62. The graphical representation, as above, of the limit for solubility of cholesterol in a 100 millimolar solution of a mixture of the six bile salts in relative amounts as in human bile, to which lecithin from human bile is added was practically identical to the corresponding curve for a 100 millimolar solution of glycochenodeoxycholate with additions of purified egg lecithin (Fig. 2.). The starting point on the horizontal axis for the curve representing mixed bile salts could be calculated — with fair approximation — from the cholesterol dissolving capacities of the individual bile salts in the mixture. The graphical representations of the limits for solubility of cholesterol in 50 millimolar, 100 millimolar and 200 millimolar aqueous solutions of sodium taurodeoxycholate to which purified egg lecithin was added in varying amounts did not show any certain differences from each other. Two purified egg lecithins of greatly different fatty acid pattern (Table 1) isolated from eggs of hens fed linoleic acid deficient diets and linoleic acid rich diets respectively, did not show any certain difference from each other with respect to cholesterol dissolving capacity when added in varying amounts to a 100 millimolar solution of sodium taurodeoxycholate.

Notizen: Zusammenfassung Durch eine quantitative radiale Immunodiffusion und Elektrophorese in albuminhaltigem Agar-Agarose-Gel wurden die Verschiebungen in den Serum-Lipoproteinen in der Fetalperiode der Neugeborenen verfolgt. Bei der Geburt konnte ein Übergewicht (relativ) von einer Fraktion mit Mobilität wie Prä-Beta-Lipoprotein und ein niedriges Alpha- und Beta-Lipoprotein nachgewiesen werden. Letztes stieg in der ersten Woche nach der Geburt fast linear mit dem Alter in Tagen, erreichte aber nicht den Serum-Lipoproteinwert der Mutter. Beim Vergleich der Konzentration von Serum-Beta-Lipoprotein bei Neugeborenen mit Geburtsgewicht und Kost, konnte der niedrigste tägliche Zuwachs bei Neugeborenen mit Geburtsgewicht unter 2500 g gefunden werden. Bei Kindern (Geburtsgewicht über 2500g) mit Muttermilch unter Zugabe von „half skimmed milk“ (E) ernährt, ergab sich der höchste tägliche Zuwachs von Beta-Lipoprotein. Die Ergebnisse wurden auf Grundlage der vorliegenden Literatur über die Physiologie der Lipid Metabolisme der Geburtsperiode besprochen.

Notizen: Zusammenfassung In Rattenversuchen wurden die biologischen Funktionen der noch nicht identifizierten Nahrungsfaktoren weiter präzisiert. Die von der Darm-Mikroflora synthetisierten Faktoren üben im höheren Tierorganismus ausschließlich Wachstumsfunktionen aus, wogegen die nur in höheren Pflanzen enthaltenen Faktoren außerdem auch für die Fortpflanzung sowie für die Entwicklung und Funktionstüchtigkeit mehrerer Organe notwendig sind.

Notizen: Zusammenfassung Die Fettsäureverteilung und der Gesamtgehalt an Fettsäuren und E-Vitamin im Serum wurde in den Tagen nach der Geburt der Neugeborenen verfolgt und mit den Werten der Mutter und teils mit den Werten der der Kinder angebotenen Nahrung verglichen. Beim Vergleich der polyungesättigten Fettsäuren mit dem E-Vitamingehalt in der Babykost konnte festgestellt werden, daß mit der Ernährung durch eine europäische Kost kein Risiko für einen relativen E-Vitaminmangel vorliegt und damit normalerweise kein nahrungsbestimmtes Risiko für eine peroxidative Hemolyse vorhanden ist. Andererseits sind Befunde über einen niedrigen E-Vitamingehalt bei Geburt von Kindern mit Geburtsgewicht unter 2500 g, jedoch ein normaler Gehalt bei Kindern mit Geburtsgewicht über 2500 g festgestellt worden. Das erste Verhältnis muß durch einen herabgesetzten Transport des E-Vitamines durch die Placenta erklärt werden. Der Fettsäuregehalt im Serum in der Geburtsperiode konnte beträchtliche Änderungen aufweisen. So ist der Gesamtgehalt an Fettsäuren im Geburtsaugenblick mehr wie zweimal so niedrig wie der der Mutter. Der Arachidonsäuregehalt ist höher, während der Linolsäuregehalt niedriger ist als der der Mutter. Innerhalb der ersten Tage nach der Geburt sank der Linolsäuregehalt relativ im Serum, während der Gehalt an Palmitinsäure stieg. In den folgenden vier Tagen stieg die Linolsäuremenge, während die Palmitinsäuremenge sank. Die Ölsäure stieg relativ während der ganzen Periode hindurch, während Stearinsäure und Arachidonsäure absanken. Obenerwähnte Änderungen in der Fettsäureverteilung wurden durch eine Regressionsanalyse statistisch behandelt und in Beziehung zu Kost, und Geburtsgewicht gesetzt. Zum Schluß wurden die Ergebnisse auf Grundlage der vorliegenden Literatur über die Physiologie der Geburtsperiode besprochen.

Notizen: Zusammenfassung Für die etwa 5500 einbezogenen Haushalte wird der Verbrauch an Lebensmitteln, die Zufuhr an Calorien und Nährstoffen sowie die Höhe der Bedarfsdeckung an wichtigen Nährstoffen nach Bundesland, Betriebsgröße, AK-Besatz, Erzeugungsrichtung dargestellt. Im Mittel wird die wünschenswerte Höhe der Nährstoffzufuhr nach allen Kriterien erreicht. Einzelwerte geben jedoch unzureichende Zufuhren, im wesentlichen an Protein, Calcium, Thiamin, andererseits aber auch überreichliche Zufuhren, vornehmlich an Reinfett, Protein tierischer Herkunft, Niacin zu erkennen.

Notizen: Summary Groups of young female hamsters were reared for 56 to 64 days on the following diets: 1. A basal diet having rice starch as the carbohydrate component and containing no added fat. 2. The basal diet modified by incorporation of 10% hydrogenated palm oil at the expense of the same weight of rice starch. 3. The basal diet modified by incorporation of 10% of a mixture of 4 parts of hydrogenated palm oil and 6 parts of sunflower seed oil at the expense of the same weight of rice starch. At the end of the feeding period the molar ratio between lipid-soluble phosphorus and cholesterol in the bladder bile was lowest with diet no. 1, slightly but not significantly higher with diet no. 2, and considerably and significantly higher with diet no. 3. The gain in weight of the animals was almost the same with diet no. 2 as with diet no. 3, and significantly greater than with diet no. 1.

Notizen: Zusammenfassung Es werden allgemeine Faktoren für die Berechnung des Caloriengehaltes gemischter Nahrung aus dem Gehalt an Fett, Protein und Kohlenhydraten aufgestellt. Die Grundlage bilden die speziellen Faktoren nach demAtwater-System und die gegenwärtige Zusammensetzung der Nährstoffversorgung in der Bunderepublik Deutschland. Die Voraussetzungen für eine sachgemäße Anwendung dieser Faktoren werden dargestellt.

Notizen: Zusammenfassung 80 männliche Sprague-Dawley-Ratten erhielten über 4 Wochen eine Diät mit 20% Rotbarschöl. In der 5. Woche wurde anstelle des Rotbarchöles eine Diät mit 10% Cocosfett und von der 6. Woche an mit 20% Cocosfett bis zur 27. Woche gegeben. Die Kontrollgruppe erhielt eine Diät mit 4% Fett (Altromin). Nach 4 Wochen Rotbarschöl entfielen in den Nierenlipiden 2,4% der Gesamtfettsäuren auf Docosahexaensäure, 8,2% auf Pentaensäuren, 9,8% auf Tetraensäuren und 8,3% auf Diensäuren. Nach Umstellung der Diät von Rotbarschöl auf Cocosfett vermehrte sich die Linolsäure von 6,7 auf 13,5% nach einer Woche Cocosfett, stieg auf 14,4% nach 11 Wochen Cocosfett und sank schließlich auf 5,8–7,8% bei Versuchsende. Die Arachidonsäure stieg von 9,3 auf 11,1% nach 1 Woche Cocosfett und erhöhte sich auf 18–20,9% am Ende der Cocosperiode. Die Halbwertszeit der Docosahexaensäure beträgt im Nierengewebe etwa 10 Wochen. Die beiden Docosapentaensäuren Ω 3 und Ω 6 fielen von 0,3 bzw. 0,8% bis zum Versuchsende auf 0,1% ab. Ihre Halbwertszeiten betrugen 22 Wochen (Ω 6) und 6 Wochen (Ω 3). Die Halbwertszeit Eicosapentaensäure Ω 6 betrug 1 1/2 Wochen und die der isomeren Ω 3-Säure 4 1/2 Wochen. Die ölsäure vermehrte sich von 23,7 auf 30,1–32,9% bei Versuchsende. Laurin- und Myristinsäure stiegen leicht an, Palmitin- und Stearinsäure verminderten sich im Laufe des Versuches.

Notizen: Zusammenfassung 80 männliche Sprague-Dawley-Ratten erhielten über 4 Wochen eine Diät mit 20% Rotbarschöl. In der 5. Woche wurde anstelle des Rotbarschöles 10% Cocosfett und von der 6. Woche bis zur 27. Woche 20% Cocosfett gegeben. Die Kontrollgruppe erhielt eine Standarddiät mit 4% Fett (Altromin). Nach 4 Wochen Rotbarschöl entfielen in den Herzmuskellipiden 7,9% der Gesamtfettsäuren auf Docosahexaensäure, 3,9% auf Pentaensäuren, 7,65% auf Tetraensäuren und 6,7% auf Diensäuren. Nach Umstellung der Diät von Rotbarschöl auf Cocosfett stieg die Linolsäure von 6,4% bis auf 24,3% nach 4 Wochen Cocosfett an. Bis zur 11. Woche Cocosfett blieb der Linolsäuregehalt des Myokards bei 19% und sank bis zum Versuchsende auf 9,4–12,6% ab. Gleichzeitig vermehrte sich Arachidonsäure von 7,6 auf 14,3%. Die Halbwertszeit der Docosahexaensäure beträgt 6–7 Wochen. Die Docosapentaensäure Ω 3 stieg auf 1,6% (C 2, C 3) an und sank bis Versuchende auf 0,4% ab. Ihre Halbwertszeit betrug 7 Wochen. Die Docosapentaensäure Ω 6 stieg von 0,1% (R 4) bis auf 1,4% bei Versuchsende. Die Halbwertszeiten der Eicosapentaensäuren waren bei unserer Versuchsanordnung nicht exakt bestimmbar. Die gesättigten Fettsäuren vermehrten sich im Myokard nicht wesentlich. Entsprechend der Abnahme der Polyenfettsäuren stiegen unter Cocosfütterung Palmitoleinr und Olsäure an.

Notizen: Zusammenfassung Bei männlichen Jugendlichen zwischen 6–16 Lebensjahren, die sportlich tätig waren, wurden mittels der anthropometrischen Methode, die Hautfaltengrößenbestimmung, nach der Methode der WHO (J. B.Jeliffe), der Röntgenhistometrie und mit dem Ultraschallecholotverfahren vergleichend der Fettgehalt und das Magergewicht — welches mit der Muskulatur in engem Zusammenhange steht — bestimmt. Die verschiedenen Methoden können zur gegenseitigen Kontrolle der Ergebnisse verwendet werden.