FIGURE 2a. Tobacco pith tissue cultured on control

nutrient medium with Indolacetic acid (IAA) but without kinetin.

FIGURE 2b. Same tissue, with kinetin.

FIGURE 3. Separated cells from embryonic structures and their development when repacked and cultured as masses.

C=cartilage

mt kidney tubules

FIGURE 3. Separated cells from embryonic structures and their development when repacked and cultured as masses.

C=cartilage

mt-kidney tubules

RESIDUAL STRESSES IN STRUCTURAL STEEL COLUMNS

(Dr. Lynn S. Beedle, Lehigh University, investigator) Investigations conducted by Dr. Beedle with the help of a National Science Foundation grant produced findings as to the load-carrying capacities and fundamental behavior of certain types of steel columns which are of considerable significance in the field of civil engineering and of special importance to the building, shipbuilding, and other industries using rolled or extruded metal shapes. In recognition of his work on this subject, Dr. Beedle received the 1955 Research Award of the American Society of Civil Engineers.

Residual stresses in structural steel components of buildings and ships often cause premature and sudden failure. (This fact was evidenced by several ship failures during World War II when ships broke in two while at sea due to residual welding stresses.) Residual stresses are also a problem in any structure which uses materials which experience a heat treatment during the manufacturing process. For example, during the manufacture of steel wide-flange columns when the column emerges from the rolling mill during the manufacturing process, it is at uniform high temperature. However, the rate of cooling of the edges of the flange is much higher than the rate of cooling in the central portion of the flange. Consequently, when normal temperatures are reached residual stresses result due to the nonuniform cooling process. Sometimes these stresses are larger in magnitude than the stresses expected due to the load on the structure to be built from the columns. In the case of rolled columns, the residual stresses due to cooling are tension in the central portion of the flange and compression in the exterior portions. Dr. Beedle's findings regarding the effect of these residual stresses upon the load-carrying capacity or buckling characteristics of columns have placed the design of structural elements on a more sound basis than heretofore and should result in considerable economies in structural designs utilizing rolled steel shapes.

With NSF support, Dr. Beedle is pursuing the findings of the initial study with a view to developing specific design criteria for use in the field of structural engineering.

SOLAR ENERGY

(Dr. J. A. Duffie, University of Wisconsin, investigator)

The National Science Foundation has actively supported and stimulated basic research in solar energy in the belief that scientific progress in this field holds great promise for all mankind. The Foundation supported a symposium on the utilization of solar energy at the University of Wisconsin in 1953 and, along with several other sponsors, a conference on the use of solar energy at the University of Arizona in 1955. Of greatest note to date, in terms of specific projects supported, has been the work of Dr. J. A. Duffie, who was awarded a National Science Foundation grant to study the application of solar energy. Dr. Duffie determined the amount of usable radiation reflected and emitted by various materials during hours of daylight and darkness and determined the heat absorbed in solar water heaters as heat collectors. Among the promising developments of these studies was Dr. Duffie's light-dark engine which used sunlight and shading for pumping liquids.

As a result of this work, Dr. Duffie was awarded a $250,000 grant from the Rockefeller Foundation for further study of the application of solar energy.

EFFECT OF ELEVATION ON DISTRIBUTION OF ARACHNIDS

(Dr. C. Clayton Hoff, University of New Mexico, investigator)

By means of NSF support, Dr. Hoff has studied the effects of elevation upon the distribution of arachnids. During the course of these ecological studies, he has found 17 species of pseudoscorpions never before reported in scientific literature.

From a more immediate and practical standpoint, Dr. Hoff's investigations have contributed significantly to existing knowledge of the life cycles and environmental requirements of many spiders, scorpions, and ticks which are native pests to the Southwestern United States. This new knowledge may prove to be important in dealing with certain diseases of domestic animals and of human beings, such as those transmitted by mites, ticks, etc.

LOW-TEMPERATURE SCIENCE

(Dr. John R. Pellam, California Institute of Technology, investigator) Research conducted by Dr. Pellam with NSF support resulted in a superfluid wind tunnel-one of the most significant recent developments in low-temperature science.

Hydrodynamicists have always dreamed of a frictionless fluid which could be used in testing their mathematical theories. Dr. Pellam capitalized on the fact that helium, below 2° K, is known to have no viscosity. In this experiment, an aerodynamic foil was exposed to a controlled flow of superfluid helium. The lift of the foil was examined under various conditions of flow of the superfluid. The results indicate that there is no lift in this perfect fluid demonstrating very dramatically the validity of an assumption physicists have wondered about for decades.

This experiment constitutes the first case of hydrodynamic flow about an obstacle in a truly frictionless fluid with a viscosity coefficient of zero. While it is too early to speculate upon the practical application of this basic discovery, its very nature presages future significance in several different areas of applied research and development.

ALGAE IN ARID AREAS

(Dr. Lora M. Shields, New Mexico Highlands University, investigator) Fundamental research conducted by Dr. Shields and supported by the National Science Foundation has produced findings which open up interesting and critically important possibilities of improving the fertility and stability of arid soils through inoculation with algae.

Erosion of arid and semiarid soils is a too well known phenomenon in this country. Low annual rainfall in certain areas and other environmental factors are responsible for the development of a series of soil conditions which ultimately lead to a rather great tendency for water and wind erosion to occur. Crusts which form in the top layers of these soils following infrequent precipitation tend to reduce water infiltration, thereby increasing runoff and consequent erosion. This soil usually supports little plant life of the type which could raise the fertility and the desirable structural qualities of the soil. However, scientists have found within the past few years that the surface crust in certain areas of arid soil contains a meshwork of minute plants and that crusts containing such algae do not retard infiltration. Thus the soil is able to receive full benefit of any precipitation that does occur.

In an important new discovery, Dr. Shields has found that this relatively thin layer of algae contributes enormously to the improvement of soil conditions. Amino nitrogen produced by the algae evidently percolates downward from the soil surface and permits existence of vegetation which could not otherwise survive in the arid environment. The soil nitrogen supply in these algal crusts has been found to be as much as 1,500 times as great as that in the soil 12 inches beneath. It is significant scientifically that these algae develop and remain under the rigorous environmental conditions of the desert.

While much further research is necessary, the above findings could prove to be of great economic significance to the South Central and Southwestern United States.

GENE-ENZYME RELATIONSHIPS

(Dr. Charles Yanofsky, Western Reserve University, investigator) Research carried on by Dr. Yanofsky with NSF support is augmenting considerably the existing store of scientific knowledge concerning gene action and interaction in the formation of specific enzymes.

Of the problems of fundamental significance in genetics, none is more interesting, or more difficult, than that of determining how invisibly small genes produce their striking effects on the entire organism. Heretofore, the only general theory of gene action presumes that each gene elaborates some special enzyme required to mediate a particular biochemical reaction within the cell. Dr. Yanofsky is applying techniques which may be said to constitute one of the first truly critical tests of the gene-enzyme hypothesis. Using the bread mold Neurospora, a popular organism in biochemical genetics, Dr. Yanofsky has produced strains unable to form a particular enzyme, due to a specific gene