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Proceedings of the Iowa Academy of Science

No abstract provided.

Editorial Board

Proceedings of the Iowa Academy of Science

No abstract provided.

Lycopene, The Major Pigment Of Podosordaria Leporina, Robert D. Koehn, Katherine M. Bartosh

Proceedings of the Iowa Academy of Science

The lipid-soluble pigments were extracted from the mycelium of Podosordaria leporina and analyzed by thin-layer chromatography and absorption spectroscopy. Lycopene was found to be the major pigment produced when mycelium is exposed to blue light.

Cyclic Patterns Of Central Florida Sooty Molds, D. R. Reynolds, B. R. Pohlad

Proceedings of the Iowa Academy of Science

Monographic work (Reynolds, 1970; Reynolds, 197la; Reynolds, 197lb) suggests that sooty molds exhibit distinct cyclic patterns of growth and reproduction. Furthermore, a tally of collection data recorded in other monographic work (Batista and Ciferri, 1962; Batista and Ciferri, 1963a) suggests that the sexual fruit bodies of ascomycetous neotropical sooty molds are prevalent during the drier season of the year. Asexual sooty molds may also occur seasonally (Batista and Ciferri, 1963b). A study was begun approximately two years ago to determine the reproductive unit frequency of select sooty molds at various times of the year.

A Scanning Electron Microscope And In Vitro Study Of Meliola Palmicola, R. D. Goos

Proceedings of the Iowa Academy of Science

The genus Meliola contains about 1,000 species of epiphyllic plant parasitic fungi that produce mycelia with characteristic capitate and mucronate hyphopodia. Growth of these fungi in culture or as artifical inoculations on leaves has never been reported. This paper presents some observations on the morphology of the fungus as seen with the scanning electron microscope (SEM), and some results obtained in culture studies.

Some New Myxomycete Records For The Neotropics And Some Taxonomic Problems In The Myxomycetes, Marie L. Farr

Proceedings of the Iowa Academy of Science

New myxomycete records for the neotropics and certain taxonomic problems are discussed. Attention is focused on the genus Diachea and particularly D. bulbillosa, Badhamia obovata, Didymium leoninum, and D. fluccosum.

Spore Cleavage And The Development Of Wall Ornamentation In Two Myxomycetes, Henry C. Aldrich

Proceedings of the Iowa Academy of Science

Processes of spore cleavage, spine deposition, and continuous wall formation have been followed in Didymium iridis and Physarum flavicomum, using electron microscopy combined with cytochemistry. The periodic acid silver hexamine (PASH) technique for demonstration of polysaccharide at the ultrastructural level has been employed. Developing sporangia were fixed at 30 min. intervals. Six hours after plasmodia form noticeable blebs on the agar, the surface membrane begins to invaginate and cleaves out spores. Flattened cytoplasmic vesicles originating from dictyosomes contribute membrane to the cleavage furrows as they grow centripetally. As soon as the spores have been cleaved, spine formation begins. Spines are …

White Leghorn Egg Production During Traffic-Noise Stress, Albert Kagan, Charles J. Ellis

Proceedings of the Iowa Academy of Science

Two groups of white leghorn hens were subjected to 95 db (C) level of traffic noise and 65 db (C) level of ambient non-traffic noise. No statistically significant difference in egg production was detected between the two groups.

An Investigation Of The Possible Occurrence Of Sterols In Blue-Green Algae, Gene F. Lata

Proceedings of the Iowa Academy of Science

The blue-green algae Microcystis aeruginosa and Gleothricia echinulata, obtained from blooms in lakes of northwest Iowa, have been shown to contain at the most trace amounts of digitonin-precipitable sterols and show a low level of isotopic incorporation from l-¹⁴C-acetate into these compounds.

A Monarch Butterfly Roosting Tree In Iowa, Mary Swander

Proceedings of the Iowa Academy of Science

Monarch butterflies, Danaus plexippus, yearly roost by the thousands in certain trees during their southward autumn migration. A study of a roosting tree in Manning, Iowa, suggests that monarchs originally chose the tree for the characteristics of its maple leaves and its physical location and proximity to nectar-producing flowers. It is thought that later generations of monarchs were drawn to the tree by a combination of a residual sex attractant odor and favorable wind conditions.

Notes On Iowa Diatoms Xii: Common Diatoms Of Big Spirit Lake, Milbert Krohn, Michael Edwards, John D. Dodd

Proceedings of the Iowa Academy of Science

A natural history of the diatoms of Spirit Lake was in preparation by the senior author prior to his death in 1973. This report is derived from his notes plus some additional observations, and is published in his behalf. A table lists 139 common taxa distributed among 34 genera and notes whether these taxa occur also in Lake West Okoboji and Clear Lake.

Compositional And Textural Analyses Of Kansan And Tazewell Till In A Portion Of Northwest Iowa, Kent Van Zant

Proceedings of the Iowa Academy of Science

11 Compositional and

Kansan and Tazewell tills can be distinguished by compositional and textural properties throughout portions of Buena Vista, Cherokee, Clay and O'Brien counties in northwest Iowa. Kansan till contains more clay than silt or sand while Tazewell till is composed of nearly equal portions of clay, silt and sand. Coarse sand is more abundant in Tazewell till than Kansan till. Siliceous rounded shale grains are common in Tazewell till but scarce or absent in Kansan till. Igneous and metamorphic rock fragments are more common in the coarse sand of Kansan than Tazewell till. Significantly more carbonate grains occur …

Analytical Methods For Characterization Of Fly Ash, Deniel C. Cavin, William A. Klemm, George Burnet

Proceedings of the Iowa Academy of Science

A typical power plant fly ash was characterized according to its composition and physical properties as a basis for research on iron and aluminum recovery from the ash. The methods used are standard and require facilities and instruments available in many laboratories today. The procedures include photomicroscopic observation, size separation, magnetic separation, X-ray diffraction, thermal gravimetric analysis, differential thermal analysis, electron microprobe analysis and emission spectroscopy. The results will be useful in determining in what ways and under what conditions a given fly ash may be treated to recover the metals present in a usable form. Preliminary work has been …

Limnological Features Of Some Northwestern Iowa Lakes, John R. Jones, Roger W. Bachmann

Proceedings of the Iowa Academy of Science

Quantitative information on the morphology, watershed characteristics, water transparency, water chemistry and algal crops of six Iowa lakes is summarized. Lake West Okoboji had less oxygen present in the hypolimnion in 1950-1973 than in 1919-1928, indicating an increase in eutrophication. On the basis of increasing plant-nutrient concentrations, increasing summer algal standing crops and decreasing water transparency, the lakes can be ranked thus: Lake West Okoboji, Big Spirit Lake, Lake East Okoboji (including Upper Gar and Minnewashta) and Lower Gar Lake. These differences among lakes are related to the ratio of watershed area to lake volume, which controls the impact of …

Bedrock Topography Beneath The Des Moines Lobe Drift Sheet, North-Central Iowa, R. C. Palmquist, G. Bible

Proceedings of the Iowa Academy of Science

The bedrock surface beneath the Des Moines Lobe Drift Sheet in Iowa contains the junction of the paleo-drainage divides between pre-glacial north, southeast and southwest flowing drainage. The bedrock uplands containing these divides have controlled the shape and location of the Des Moines Lobe as well as the location and shape of the end moraines upon the drift sheet. The total drift thickness beneath the lobe is commonly 100 to 150 feet but ranges from 20 to 500 feet. The relatively uniform thickness of the drift means that the surface topography mimics the bedrock topography. Hummocky end moraines and three …

Front Matter

Proceedings of the Iowa Academy of Science

No abstract provided.

The Flora Of Brush Creek Canyon State Preserve, Lawrence J. Eilers

Proceedings of the Iowa Academy of Science

Brush Creek Canyon State Preserve is a scenic natural area in Fayette County, Iowa. The preserve contains steep, wooded ravines; tall, vertical outcrops of dolomitic limestone; clear streams; cascades area; and cool springs. These habitats support a variety of native plant communities, resulting in a rich flora of at least 268 species of vascular plants. Man-made disturbance is minimal, and there are several species of rare plants that increase the importance of the preserve.

Western Iowa Proboscidians, Duane C. Anderson, Patricia M. Williams

Proceedings of the Iowa Academy of Science

The present paper is a survey of Pleistocene mammoth and mastodon remains from western Iowa. Included are locality data and references to the literature for over 350 specimens from 32 of 41 counties surveyed. Mammoths are found to be more numerous than mastodons, reversing the pattern observed in the woodland areas adjoining the present-day Prairie Peninsula. The first radiocarbon date for the mastodon in Iowa (13,520± 135 B.P.) is reported from Harrison County. None of the localities surveyed have provided any evidence of early man.

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Iowa Science Teachers Journal

No abstract provided.

Ten Commandments Of Student Teaching, Michael Teets

Iowa Science Teachers Journal

Ten items of advice for student teachers.

Curriculum Materials For Iscs

Iowa Science Teachers Journal

An annotated list of new, free, teacher-constructed curriculum materials for ISCS is available upon request.

Actual Teaching Assignments Call For Broader Pre-Service Training For Chemistry-Physics Teachers, Robert W. Hanson

Iowa Science Teachers Journal

Full-time physics teachers are rare in Iowa's high schools-information on record with the Iowa Department of Public Instruction indicates that there are only eleven in the entire state. Full-time chemistry teachers are not much more common-the records show that there are 33 in Iowa. The most common combination involving physics includes chemistry, with 62.5 percent of all physics teachers teaching chemistry and 52.5 percent of all chemistry teachers teaching physics. Most of the 240 teachers who teach both subjects teach a third subject as well. Tables 1 and 2 show the numbers of teaching combinations that include chemistry or physics …

Science Articulation K-12, Gary E. Downs

Iowa Science Teachers Journal

I think it is important that we know what I am going to discuss; therefore I feel I should define articulation. Definition of Articulation - the action or manner of jointing or interrelating; the state of being jointed or systematically interrelated into a whole; interrelation of different levels of education (as elementary education, secondary education, and higher education) for ensuring continuous advancement of learning. Using this definition I would now like to take a look at our educational structure.

Free Teaching Materials

Iowa Science Teachers Journal

Single copies of the following publications will be sent free to teachers upon request for a specific title.

Candidates For Nsta Office

Iowa Science Teachers Journal

One of our neighbors, Darrell Goar, has been nominated for president of NSTA.

An Experimental Study Of The "Doctor Fox Effect", John E. Ware, Reed G. Williams

Iowa Science Teachers Journal

Colleges and universities are employing student evaluations of faculty with increasing frequency. On some campuses, the forms are used at the instructor's option and serve primarily as a source of feedback for faculty development purposes. Others require student evaluation of instruction and publish the results in academic "consumer's guides." Still others consider student evaluations of instruction in making decisions with regard to faculty salary increases, retention, tenure and promotion. The optional use of student ratings in order to improve instruction often evolves to the mandatory consideration of student rating data in making decisions about faculty retention, promotion and tenure. As …

Field Trips And Pond Water Studies, Richard Pope

Iowa Science Teachers Journal

One of the activities that the students enjoy a great deal is the study of pond water, both before and after our trip. To the student whose curiosity is stirred by the study of nature, the pond offers an unusual and interesting experience.

To Dye Or Not To Dye, A. C. Haman

Iowa Science Teachers Journal

In the beginning there was water and rock, but as plant life evolved, the globe became more colorful. Cool greens gradually enveloped the earth as successive waves of mosses, ferns, conifers and angiosperms conquered the land. In addition new pigments evolved providing artistic man with new mood-creating dyes with which to color his existence. Primitive man utilized dyes to color his skin to frighten his enemies and increase his prestige. Greek ladies, dissatisfied with the color of their hair, used buckthorn, Rhamnus, to stain their hair yellow and add to their charms. European aristocrats of the Middle Ages, traveling …

Model Rocketry - An Excellent Teaching Aid, Edward L. Pizzini

Iowa Science Teachers Journal

As unlikely as it may seem, hobbies can serve as a powerful aid in the teaching of science. They not only provide concrete examples but capitalize on the student's interest. Model rocketry activities are an excellent example of such "high involvement" learning hobbies.

Upstep Summer Conference Provides Means Of Making Curriculum Improvements, Tony Heiting

Iowa Science Teachers Journal

The UPSTEP Summer Conference for Science Curriculum Innovation and Leadership is an opportunity for teachers to work with others to make their teaching environment more effective.