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Proceedings of the Iowa Academy of Science
No abstract provided.
Officers And Past Presidents, Iowa Academy Of Science
Officers And Past Presidents, Iowa Academy Of Science
Proceedings of the Iowa Academy of Science
No abstract provided.
Water And Solute Content Of Tree Trunks, Warren E. Engelhard, Robert C. Lommasson
Water And Solute Content Of Tree Trunks, Warren E. Engelhard, Robert C. Lommasson
Proceedings of the Iowa Academy of Science
Bi-weekly samples of wood were taken from two species of conifers and three species of dicots from September to April. From the samples water content and solute content of each tree were determined. From soil samples taken beneath each tree the soil moisture was determined. The water content in the dicots was high in winter and low in the fall and spring, and in the conifers it was high in the fall and decreased through the winter to low values in the spring. Soil water influenced the water content of the trees only in minor details. The solute content of …
The Development Of Ear Prirnordia Of Zea In Relation To Position On The Plant, John E. Sass
The Development Of Ear Prirnordia Of Zea In Relation To Position On The Plant, John E. Sass
Proceedings of the Iowa Academy of Science
The development of auxiliary buds of a yellow dent maize hybrid was studied. Seven buds at acropetally successive nodes survived at least to 68 days after planting and became pistillate inflorescences, potential ears. Meiosis occurred in the basal ovaries of the upper two ears after 68 days, when the styles were 2 mm. long, and complete embryo sacs were present by 71 days. The two upper ears attained approximately the same morphological and cytological stage between 68 and 71 days. The top bud invariably became the harvestable ear. The failure of complete development of the second ear is not ascribed …
Development Of The Helicoid Andscorpioid Cymes In Myosotis Laxa Lehm. And Mertensia Virginica L., Paul V. Prior
Development Of The Helicoid Andscorpioid Cymes In Myosotis Laxa Lehm. And Mertensia Virginica L., Paul V. Prior
Proceedings of the Iowa Academy of Science
The vegetative and inflorescence apices of Myosotis laxa and Mertensia virginica have been compared and contrasted in order to determine how helicoid and scorpioid cymes differ in development. The apices have been interpreted on the basis of the tunica-corpus theory, since no clear histogenic layers could be determined for these species. The stem apex enlarges and broadens at the onset of flowering, and apical dominance is lost. The number of tunica layers is reduced in both cases, and the enlargement of the apex is found to be due to more, not larger cells. The helicoid cyme of Myosotis laxa results …
A Pure Culture Technique For Studying The Infection Phenomenon Of Oak Roots By Armillaria Mellea, George Varghese
A Pure Culture Technique For Studying The Infection Phenomenon Of Oak Roots By Armillaria Mellea, George Varghese
Proceedings of the Iowa Academy of Science
Oak seedlings were grown in a pure culture of A. mellea in large test tubes. A layer of white quartz sand, in which an acorn was planted, covered a PDA medium containing rhizomorphs of the fungus. After four months growth, roots from the oak seedlings were extracted from the agar, washed, fixed in FAA, sectioned, stained, and examined microscopically. Abnormal areas of the tap roots showed epidermis demarcated by a black layer of suberized cells. One section showed this suberized layer broken by penetration of a foreign object. The cortex around this penetration point was disrupted and stained a dark …
Histological And Histochemical Study Of The Roots Of Zamia Floridana And The Endophytic Alga Contained In Them, Ronald Meyer
Histological And Histochemical Study Of The Roots Of Zamia Floridana And The Endophytic Alga Contained In Them, Ronald Meyer
Proceedings of the Iowa Academy of Science
Some of the epigean roots are found to contain an endophytic blue-green alga, Anabaena cycadearum; others are free of algae but are later invaded. Normal roots and algal-free roots possess a diarch protostele; algal-infected roots have a triarch protostele. The normal root has an epidermis which in the other roots is sloughed off and replaced by a leathery phelloderm. The algal-infected root contains in the mid-cortex a wide area filled with algal cells and spanned at infrequent intervals by starch-free layer, radially elongated cortical cells. The algal-free root contains a starch-free layer of cells in the mid-cortex which are believed …
Notes On Iowa Fungi. Xiv, G. W. Martin
Notes On Iowa Fungi. Xiv, G. W. Martin
Proceedings of the Iowa Academy of Science
Comments are made on the five species of M orchella native to Iowa, with particular reference to M. deliciosa. Other fungi are briefly noted.
A Hypothesis To Account For Unusual Leaf Variation In Viola Pedata L., Norman H. Russell, William R. Bowen
A Hypothesis To Account For Unusual Leaf Variation In Viola Pedata L., Norman H. Russell, William R. Bowen
Proceedings of the Iowa Academy of Science
Viola pedata L., the birdfoot violet, occasionally displays unusual variation in leaf shape in the southeastern United States. No satisfactory explanation for this has yet been provided. Analyses of variation in a colony with normal leaf shapes, one with the unusual leaf variants, and a neighboring population of Viola primulifolia L. subsp. villosa (Eaton) Russell leads to the hypothesis that the leaf variation is due to hybridization and subsequent introgression between V. pedata and V. primulifolia subsp. villosa.
The Reorientation Of Calcite Crystals In Limestone, Sharon Curry
The Reorientation Of Calcite Crystals In Limestone, Sharon Curry
Proceedings of the Iowa Academy of Science
Limestone from the Hampton Formation at Ferguson, Iowa, was studied in an effort to determine whether the vertical force of overburden had caused preferential orientation of crystals. Results are insufficient to indicate the extent of recrystallization caused by overburden; there is evidence that there has been horizontal influence also. Petrofabric diagrams are included.
Stratigraphic Studies Of The Gilmore City Formation At Rutland, Iowa, James K. Wagner
Stratigraphic Studies Of The Gilmore City Formation At Rutland, Iowa, James K. Wagner
Proceedings of the Iowa Academy of Science
An interesting relationship between the beds of limestone and dolomite in a quarry and at outcrops along the Des Moines River near Rutland, Iowa, is described. In the quarry a composite of 11 feet of limestone-dolomite-limestone is exposed, whereas at an outcrop along the river 300 feet northeast the dolomite is absent and 12 feet of limestone is exposed. These beds of limestone and dolomite have been referred to the St. Louis formation uncomformably overlying Gilmore City limestone. The author proposes that the dolomite represents an area of late diagenetic alteration within the Gilmore City formation.
Geological Age Of Soldier Creek Buffalo County, South Dakota, Alan H. Coogan
Geological Age Of Soldier Creek Buffalo County, South Dakota, Alan H. Coogan
Proceedings of the Iowa Academy of Science
A quantitative analysis of data derived solely from maps of Soldier Creek and a comparison with similar data from Good Soldier Creek show Soldier Creek to be a composite stream of several branches which differ in drainage composition and which therefore probably differ in origin. A study of the field evidence bearing on anomalous factors in the quantitative analysis shows Soldier Creek was formed by the capture of several post-Iowan streams by a younger post-Cary stream.
Stabilization Of A Calcareous Loess With Calcium Lignosulfonate And Aluminum Sulfate, T. Demirel, Donald T. Davidson
Stabilization Of A Calcareous Loess With Calcium Lignosulfonate And Aluminum Sulfate, T. Demirel, Donald T. Davidson
Proceedings of the Iowa Academy of Science
This paper describes a promising method of stabilizing calcareous Wisconsin-age loess with a combination treatment of spent sulfite liquor and aluminum sulfate. The stabilization is thought to be due to formation of water-insoluble basic aluminum lignosulfonate in the compacted soil.
A Revision Of A Completion Method For Inverting Matrices And Its Adaptation To Ill-Conditioned Matrices, William L. Waltmann
A Revision Of A Completion Method For Inverting Matrices And Its Adaptation To Ill-Conditioned Matrices, William L. Waltmann
Proceedings of the Iowa Academy of Science
An essentially new method for the inversion of n x n matrices, closely related to the method of completion attributed to Sherman, Morrison, and Bartlett, is presented. This revised technique has the added advantages that it can be used for any square matrix, regardless of its conditioning state, and that it can be readily adapted to electronic digital computers.
Error Terms Of Numerical Integration Formulas, Robert J. Lambert
Error Terms Of Numerical Integration Formulas, Robert J. Lambert
Proceedings of the Iowa Academy of Science
This paper gives a proof that the polynomial function Qn (s) = ∫so t(t-1) (t-2) • • • (t-n)dt does not change sign on the interval (O,n). Heretofore it was generally believed that Qn (s) changed sign on the interval (O,n) when n was an odd integer. The technique of proof is to show that when n is odd, Qn (s) has an upper bound Qn (n-1) for (n-1)/2 ≤ s ≤ n which is shown to be negative. This result simplifies the treatment of the error terms in certain numerical integration formulas which …
Morphology Of Frost Polygons As Related To Ground Slope In Eastern Greenland, Robert Duncan Enzmann
Morphology Of Frost Polygons As Related To Ground Slope In Eastern Greenland, Robert Duncan Enzmann
Proceedings of the Iowa Academy of Science
This paper describes polygonal frost-patterned ground on level terraces, modification of the polygons by solifluction to garlands on slopes of 5° to 35°, modification of the garlands to rock stripes on slopes of 20° to 45°, collapse of stripes into jumbled rock glaciers on slopes of 35° to 60°, or more commonly, modification of stone stripes back through the sequence of stripes and garlands where the slope shallows toward the valley floor. The subsurface structures of eight polygons, two garlands, and two stone stripes were exposed by trenching. The garlands and stone stripes were on a slope lying between a …
A Theoretical Study Of A Randomly Excited Mechanical Oscillator, Victor W. Bolie, Francis M. Long
A Theoretical Study Of A Randomly Excited Mechanical Oscillator, Victor W. Bolie, Francis M. Long
Proceedings of the Iowa Academy of Science
A mathematical investigation is made of the feasibility of extracting usable mechano-electric power from a critically damped and randomly excited mechanical oscillator. Two different analytic functions are used to approximate practical squared-velocity spectra for the motion of the vehicle supporting the oscillator, and the corresponding expressions for extractable power are developed. Numerically computed results are presented graphically to illustrate the effects of varying the oscillator parameters.
A Note On Dialectics In Mathematics, William A. Small
A Note On Dialectics In Mathematics, William A. Small
Proceedings of the Iowa Academy of Science
A complete dialectical process is defined; it is shown that such a process is a function, and that every real function is a complete dialectical process. Some general implications of this result are discussed.
Connecting Rod Forces In The Horizontal Engine, Victor W. Bolie
Connecting Rod Forces In The Horizontal Engine, Victor W. Bolie
Proceedings of the Iowa Academy of Science
Four equations define the effects of gravity, linkage and piston geometry, engine speed, inertia and mass of the rod and piston, thickness and viscosity of the oil film, and pressure in the crankcase and the combustion chamber. The equations were programmed for automatic digital computation, with typical values for the 15 parameters. The results are illustrated by graphs of the piston-head pressure and the tensile and normal forces acting on each end of the rod as functions of crankshaft rotation.
Correlates Of Achievement In A Veterinary Medicine Curriculum, Thomas E. Hannum
Correlates Of Achievement In A Veterinary Medicine Curriculum, Thomas E. Hannum
Proceedings of the Iowa Academy of Science
A correlational study was made of test scores and achievement of Veterinary Medicine students who graduated in the spring of 1959 from Iowa State University. Cumulative grade point averages were obtained at the time of graduation and correlated with selection data obtained at the time of admission to the College of Veterinary Medicine in the fall of 1955. These data included: pre-veterinary grade point averages; interest scores on the Strong Vocational Interest Blank; Veterinary Aptitude Test scores; American Council on Educational Psychological Examination (College Edition), Quantitative and Linguistic scores; and numerical ratings made by a faculty committee during screening interviews …
The Influence Of The Antithyroid Drug, Propylthiouracil, On Reproduction In Rats, Kenneth M. Cook
The Influence Of The Antithyroid Drug, Propylthiouracil, On Reproduction In Rats, Kenneth M. Cook
Proceedings of the Iowa Academy of Science
The antithyroid drug, propylthiouracil (PTU), when fed to white rats at the dietary level of 0.1 percent PTU in finely ground laboratory chow for ten weeks prior to mating, does not affect the ability of either male or female rats to reproduce. All metabolic evidences examined indicate a lower metabolism under the influence of PTU. The PTU dietary treatment was ceased at conception of PTU females. Characteristics of the offspring did not differ from those produced by mothers maintained on normal laboratory chow throughout the experiment.
Direct And Indirect Measurements Of Arterial Blood Pressure In Normal And Propylthiouracil-Treated Rats, Lloyd Hoffman
Direct And Indirect Measurements Of Arterial Blood Pressure In Normal And Propylthiouracil-Treated Rats, Lloyd Hoffman
Proceedings of the Iowa Academy of Science
Systolic and diastolic blood pressures were lowered in male rats by treatment with 0.1 percent dietary propylthiouracil for a period of ten to twelve weeks. At the best comparison levels systolic pressure measurements of experimental rats dropped 15.0 percent by the indirect method and 26.9 percent by the direct method when compared to the levels of control rats. The diastolic values of experimental animals dropped 18.3 percent as measured by the indirect method and 28.9 percent as measured by the direct method when compared to controls. Thus, the hypothyroid state induced by the drug propylthiouracil is accompanied by reduced systolic …
Altered Growth Of Animals After Continual Centrifugation, Charles C. Wunder
Altered Growth Of Animals After Continual Centrifugation, Charles C. Wunder
Proceedings of the Iowa Academy of Science
Two different animals have demonstrated an accelerated growth after prolonged centrifugation. This report is primarily concerned with larvae of the common fruit fly, Drosophila melanogaster, after 24 hour periods of centrifugation at fields between 2200 and 3300 G's. Similar studies are reported for the laboratory white mouse, Mus musculus after seven days of centrifugation at 7 G's. The faster growth is possibly due to more efficient growth, resulting as an adaptation to greater gravity. Such a suggestion is supported by the finding that centrifuged larvae exhibit a reduced oxygen requirement for growth.
Comparative Study Of Effects Of Gravity On The Growth Of Hamsters And Mice, Stanley R. Briney, Charles C. Wunder
Comparative Study Of Effects Of Gravity On The Growth Of Hamsters And Mice, Stanley R. Briney, Charles C. Wunder
Proceedings of the Iowa Academy of Science
Syrian golden hamsters appear to withstand gravitational stress better than white mice. When these animals were subjected to four weeks of continual centrifugation at four times the Earth's gravity (4 G's), both showed a definite decrease in body mass during the first week, then a subnormal growth rate for the remaining three weeks of exposure as compared to their controls living within the Earth's gravity (1 G).
The Effect Of Kinetin On The Rate Of Multiplication Of Paramecia, Mary Annunciata Mcmanus, Kathleen Sullivan
The Effect Of Kinetin On The Rate Of Multiplication Of Paramecia, Mary Annunciata Mcmanus, Kathleen Sullivan
Proceedings of the Iowa Academy of Science
A stimulation of the rate of division of Paramecium caudatum by kinetin has been reported. This paper reports investigations in which kinetin was found to be inhibitory, rather than stimulatory, to division of paramecia under similar conditions and at the same concentrations. Addition of IAA apparently counteracted the inhibition produced by kinetin.
Effects Of Capillary Permeability On Tracers In The Blood, Victor W. Bolie, Neal R. Cholvin
Effects Of Capillary Permeability On Tracers In The Blood, Victor W. Bolie, Neal R. Cholvin
Proceedings of the Iowa Academy of Science
Numerous advantages arise from a concise mathematical formulation of the influence of capillary permeability on tracers in the blood. The paper deals with a theoretical description of the depletion of a blood-borne tracer under the combined influences of the reversible process of transcapillary diffusion and irreversible processes such as renal excretion and first-order enzymatic degradations. Numerical calculations are illustrated graphically to show application of the theory to typical tracer dilution problems.
Problems Of The Mechanism Involved In The Metamorphosis Of Bugula And Amaroecium Larvae, William F. Lynch
Problems Of The Mechanism Involved In The Metamorphosis Of Bugula And Amaroecium Larvae, William F. Lynch
Proceedings of the Iowa Academy of Science
Various treatments which induce precocious fixation or inhibit attachment of Bugula and Amaroecium larvae are reviewed. Heilbrunn's general theory of stimulation and anesthesia is thought to provide a fairly suitable explanation for the artificial induction or inhibition of metamorphosis of Bugula larvae, but the agents causing induced metamorphosis resemble those which affect cell division more than those which affect muscle contraction, a necessary correlate of the hypothesis. The hypothesis applied to Bugula larvae does not seem to offer a suitable explanation for induced metamorphosis in some ascidian tadpoles.
An Ecological Catalog Of The Lake Okoboji Gastropods, Richard V. Bovbjerg, Martin J. Ulmer
An Ecological Catalog Of The Lake Okoboji Gastropods, Richard V. Bovbjerg, Martin J. Ulmer
Proceedings of the Iowa Academy of Science
A five year survey was made of the gastropods of Lake West Okoboji, Iowa. Only 11 species comprise the present fauna, a remnant of what was earlier in this century several times larger. These species are: Amnicola limosa (Say), Amnicola lustrica Pilsbry, Ferrissia rivularis (Say), Gyraulus parvus (Say), Helisoma trivolvis (Say), Lymnaea reftexa Say, Lymnaea obrussa Say, Menetus exacuous (Say), Physa gyrina Say, Physa sayii Tappan, and Valvata tricarinata (Say). These are now confined to areas less than 10 meters in depth with numbers of species and densities much greater in the bays than in the main body of the …
The Effect Of Temperature And Light Upon The Phenotypes Of Some Collembola, Mary F. Willson
The Effect Of Temperature And Light Upon The Phenotypes Of Some Collembola, Mary F. Willson
Proceedings of the Iowa Academy of Science
Of five species reared under different conditions of temperature and light, only Hypogastrura matura exhibited a phenotypic difference. This difference was in the relative lengths of the furcula and the head and appeared to be a matter of selective survival rather than a direct response of the phenotype to the environment.
Some Blood Parasites From Birds In Central Iowa, John N. Farmer
Some Blood Parasites From Birds In Central Iowa, John N. Farmer
Proceedings of the Iowa Academy of Science
During 1957, 1958, and 1959, blood smears from 568 birds were examined. Ninety-nine (17.25%) of these birds were found to harbor haemosporidian parasites. Four species of birds harbored Plasmodium, four species were infected with Leucocytozoon, and five species with Haemoproteus. Trypanosomes and microfilariae were observed in two species.