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The CO binding properties of monomeric (Hb III and IV), dimeric, and tetrameric Chironomus haemoglobins as well as of the monomer-analogue valence hybrid (α2Mmet βmet βdeoxy) of Hb M Iwate were studied and compared with the respective O2 binding properties. All these haemoglobins show hyperbolic O2 binding curves and a Bohr effect. The amplitudes of the O2 Bohr effect curves range from Δlog pO2(½) = 0.3 (Hb III) to 2.4 (tetrameric Chironomus haemoglobin). The ligands CO and O2 differ not only in affinity but also with regard to the Bohr effect. The CO affinities of the various Chironomus haemoglobins are 60 to 490 times larger than the O2 affinities and the amplitudes of the CO Bohr effect curves are 1.25 to 8 times smaller than those of the respective O2 Bohr effect curves. In the case of Hb M Iwate, however, the CO Bohr effect is larger than the O2 Bohr effect by the factor 1.25 (2,3-bisphosphoglycerate-reacted Hb M) and 1.4 (stripped Hb M). The ligand-specific differences in the magnitude of the Bohr effect cannot be explained solely by the allosteric interaction connected with the trans-effect of the complex. The differences are discussed in terms of steric influences on the binding geometry of the 6th ligand by protein side chains at the distal side of the haem group.

The effect of column geometry and dynamics on the infraction of glycerokinase and lactate dehydrogenase with N6-(6-aminohexyl)-5'-AMP-Sepharose has been studied. The strength of the enzyme-ligand interaction and the capacity of the adsorbent were shown to be complex functions related to column geometry, ligand concentration and total amount of ligand. The bed geometry had a significant effect on the strength of the interaction at low ligand concentrations and a particularly pronounced effect on interacting systems of relatively low affinity. Enzyme retardation was dependent upon ligand concentration and was independent of the concentration of both the applied enzyme sample and inert protein. The enzyme-ligand interaction, under column conditions, was shown to be a time-dependent process and evidence is presented to show that both the resolution and strength of interaction can be enhanced by increasing the enzyme-ligand equilibration time. Under batchwise conditions the apparent capacity of the adsorbent was dependent on both the enzyme concentration and the equilibration time. No difference was detected in the capacity of N6-(6-aminohexyl)-5'-AMP-Sepharose for glycerokinase and lactate dehydrogenase under batchwise conditions. [ABSTRACT FROM AUTHOR]

The contention that geography is a ‘spatial’ discipline is often interpreted to mean that a set of laws are uniquely geographic in their structure. From the viewpoint of the structure of scientific explanations, such as suggestions is unwarranted and ill-advised. With trivial exceptions, all explanations, except those of synthetic geometry, can answer aspects of geographic questions. [ABSTRACT FROM AUTHOR]

An interest in the relations between geography and geometry has been a continuing theme in geographic studies. A review of current research which is consistent with this theme reveals a greater emphasis now on the mathematics of spatial patterns and the properties of the geometries which are assumed. A challenge for geography is to combine this interest in geometries with the work on human behavior over space and to develop process theories from which the spatial patterns can be deduced. [ABSTRACT FROM AUTHOR]

This study analyzes the hydraulic geometry of the Manatí Basin, located in north central Puerto Rico. Measurements of stream width, depth, velocity, and discharge were made at ten different stations along the Río Manat´. At each station and in the downstream direction, the adjustments of stream width, depth, and velocity to stream discharge for the Manatí Basin are found to be adequately expressed by three power equations: w = aQb, d = cQf, and v =kQm. The rates of change, expressed by the values of the exponents, are found to be determined partially by the locations of sites rehtive to the river control, the cohesion of the channel materials, the roughness of the channels. and the nonuniform velocity distribution within the river. The similarity in the orderly adjustment of the Manatí channels to discharge fluctuations strongly indicates that the geometric and kinematic properties of the Río Manatí are continuously in equilibrium. [ABSTRACT FROM AUTHOR]

The article discusses the use of order neighbor statistics in a class of random patterns in multidimensional space. The study of distribution is extended to levels of geometric objects, removing the existing limitation to analysis of point patterns. Numerical results are obtained for patterns in Euclidean dimensional space. The article also discusses how statistical methods for describing pattern have been advanced by statistical ecologists.

In this article, we discuss ideas about two by two contingency tables in terms of the geometry of the three dimensional simplex. In particular, we derive the loci of points corresponding to certain classes of two by two tables. We relate the geometry to a discussion of the mean square contingency, which is also associated with rejection regions for the chi-square goodness of fit test for independence. [ABSTRACT FROM AUTHOR]

A mathematical model is developed for predicting the expected number of potential conflict situations at the intersection of air routes. Given the intersection angle of two routes and the average flows and speeds of aircraft, the model predicts the average number of potential conflict situations per unit of time. A concept of intersection capacity based on conflict situations is introduced, and a mathematical model of intersection capacity is developed. The models can be used in planning air route network geometry, as well as in providing guidelines to the establishment of suitable levels of traffic flow along various routes. [ABSTRACT FROM AUTHOR]

Four closely related minimax location problems are considered. Each involves locating a point in the plane to minimize the maximum distance (plus a possible constant) to a given finite set of points. The distance measures considered are the Euclidean and the rectilinear. In each case efficient, finite solution procedures are given. The arguments are geometrical. [ABSTRACT FROM AUTHOR]