Adipocyte cell size and number of three adipose depots, gonadal, subcutaneous, and retroperitoneal, were determined in several strains (aAy, aAiy, dbdb, obob, and NZO) of adult genetically obese mice, male and female, and in male gold thioglucose-treated mice. Epididymal pad cellularity was determined during development in yellow and viable yellow obese mice and their lean littermates, as well as in the NCS/R mouse. Cell number in the mouse epididymal pad in both lean and genetically obese animals is determined early in development, i.e., before weaning. Cell enlargement is the consistent and usually dominant morphological explanation for adipose depot enlargement in genetic and in gold thioglucose-induced mouse obesity. In some instances, hyperplasia accompanied the hypertrophy, occurring most often in the subcutaneous depot. Cell number in the subcutaneous pad of the obese–hyperglycemic female is four times that of the lean control and represents the most extreme case of hyperplasia observed. In fact, hyperplasia was consistently seen in the obob mouse. A classification for genetic obesity based primarily upon the cellularity characteristics of the adipose depots is proposed.

During high volume of flow in a stream that has considerable seasonal fluctuation, the microdistribution of five species of mayflies was determined by displacement of individuals by drift from rapid current areas to those with gentle or no current. The major effect of drift was dispersal, not depletion, of the mayfly population. Occurrence in drift is determined by a species—specific complex of interdependent factors including life cycle, microdistribution (both before and after the effect of spates), and the behavioral characteristic of individual species.

The biodegradability of several packaging films was determined; the degradation of the polymeric films, polypropylene and poly(vinyl chloride), was compared to a coated paper and several coated cellophanes. The films were buried in bacterially-active soil and the extent of bacterial degradation was determined by measuring the reduction in tensile strength as a function of burial time. The results show that the polymeric films do not degrade after five weeks of soil burial while the glassine and cellophanes do degrade. Surprisingly, the cellophane films decompose at a faster rate than the coated glassine sheet.

Sulfate concentrations in natural waters and soil-water extracts were determined semiautomatically using a lead-ion electrode to indicate the solution potential change at the endpoint, a constant flow device to deliver the titrant, a pH-mV meter to measure the potential, and a strip chart recorder to plot the solution potential thus indicating the endpoint. Sulfate concentrations as low as 0.5 meq/liter in the sample solution were determined by the potentiometric titration system. This semiautomated direct titration of sulfate has the advantages of increased sensitivity and speed as compared with the precipitation method.

The horizontal infiltration of water into uniform air-dry soil columns is examined experimentally and theoretically. The applicability of the similar media concept to the scaling of soils having a wide textural range is studied. The microscopic characteristic length is determined from plots of the distance to the wetting front as a function of the square root of time, in such a way that these plots coalesce into one line when expressed in terms of scaled coordinates. If the soil water diffusivity of one soil is known, values of the microscopic characteristic length determined by the above method can be used to estimate the soil water diffusivity of the other soils.

Apparent lignin was determined on stems and leaves of high- and low-tannin sericea lespedeza (Lespedeza cuneata [Dumont] G. Don) by two methods. One method by which tannin, other acid-soluble material, and protein are removed by detergents gave lower and more realistic lignin values than the conventional (H₂SO₄) method. Tannin was associated with high apparent lignin values when determined by the latter method. Genetic differences in lignin content among normal (high tannin) sericea lines and varieties were found, indicating that varieties lower in lignin than present ones can be developed.

The cytokinin activity in barley (Hordeum vulgare L.) caryopses (determined by the soybean [Glycine max (L.) Merr.] callus assay method) decreases very rapidly after pollination. Small caryopses, whether genetically determined, resulting from de-awning of spikes, or from damage by high water content of soil after pollination, matured earlier and had lower cytokinin activity. Differences in cytokinin content were detected earlier than those in grain size. The results suggest that plant growth substancs such as cytokinins participate in the regulation of grain size, possibly by influencing accumulation processes and the duration of the filling period. It is probable that roots also play a role in regulating grain size by supplying the spikes with plant hormones.

A model for P uptake by plants growing in the field or under controlled growth conditions was developed. The model makes allowance for the apparent diffusion coefficient of P in the soil (D), and the biologically determined parameter relating flux to concentration (α) to be concentration-dependent. The values of D(C) and α(C) were determined directly by new laboratory techniques. The phosphate soil diffusion coefficient (Dₚ) was practically independent of concentration when the volumetric water contents (θ) of the soil was 0.40. When θ was 0.57, the dependence of Dₚ on concentration increased. The dependency of α(C) on the age of a unit root surface area of corn (Zea mays L.) was taken into consideration in the model.