Education Commons^™

Applied Mathematics Should Be Taught Mixed, Gary I. Brown

Humanistic Mathematics Network Journal

No abstract provided.

Female Voices In Mathematics: A New Course, Shobha Gulati

Humanistic Mathematics Network Journal

No abstract provided.

Math: It's Not Just A Four Letter Word, Susan Byerly

Humanistic Mathematics Network Journal

No abstract provided.

Nctm Standards, Second Edition: A Review And Commentary On Zalman Usiskin's Address, Harald M. Ness

Humanistic Mathematics Network Journal

No abstract provided.

What Changes Should Be Made For The Second Edition Of The Nctm Standards?, Zalman Usiskin

Humanistic Mathematics Network Journal

No abstract provided.

Environmental Pulse In Academia, Delmar Vander Zee

Pro Rege

This feature article is based on a paper given for the 1993 Fall Faculty Lecture Series at Dordt College.

Writing Mathematics, E. G. Bernard

Humanistic Mathematics Network Journal

No abstract provided.

The Language Of Mathematics: A Quantitative Course For A General Audience, Stephanie F. Singer

Humanistic Mathematics Network Journal

No abstract provided.

Students' Understanding Of Functions In Calculus Courses, G. S. Monk

Humanistic Mathematics Network Journal

No abstract provided.

Philosophy Of Mathematics, Mathematics Education, And Philosophy Of Mathematics Education, Yuxin Zheng

Humanistic Mathematics Network Journal

No abstract provided.

Mathematics For Math Majors: Loss Of Self-Esteem, Chun-Ip Fung, Man-Keung Siu

Humanistic Mathematics Network Journal

No abstract provided.

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Influence Of Reduced Leaching On Growth Of Seedlings Of Black Locust Inoculated With Rhizobia, William R. Graves, Sandra R. Anfinson

Journal of the Iowa Academy of Science: JIAS

Seedlings of black locust (Robinia pseudoacacia L.) were inoculated with compatible rhizobia and irrigated twice each week with solution containing either 50 or 150 mg nitrogen/L. Leaching fraction treatments of 0, 0.2, or 0.4 were maintained for 6 weeks. Seedlings supplied 50 mg nitrogen/L grew poorly compared co planes supplied 150 mg nitrogen/L regardless of leaching fraction. Dry masses of shoots and of entire planes were lower for seedlings in the 0 and 0.2 leaching fraction treatments compared with chose in the 0.4 treatment. Neither leaching fraction nor applied nitrogen concentration appeared co affect the number of nodules per plant, …

Age And Developmental History Of Iowa Fens, C. A. Thompson, E. A. Bettis Iii

Journal of the Iowa Academy of Science: JIAS

Iowa fens are small, mineorotrophic peatlands maintained by shallow groundwater. Eighteen fen sites located across northern Iowa were mapped and radiocarbon dated to assess the timing of initial peat accumulation. The radiocarbon ages span the Holocene, ranging from 1,240 to 10,900 B.P.; however most fens postdate 5,000 yr B.P. The dominance of late-Holocene ages suggests that Holocene climatic change may have strongly influenced the record of peat accumulation. During the mid-Holocene Iowa was warmer and drier than at present, and peat was degraded or accumulated slowly in fens. The range of ages also implies that the commencement and subsequent rate …

The Iowa Academy Of Science Parish Farm: 1986-1992, David L. Dozark

Journal of the Iowa Academy of Science: JIAS

This article focuses on the Iowa Academy of Science Parish Farm and the progress made in the last seven years towards the goals set forth in the Model Farm Concept which was adopted by the Academy in 1970. Highlights of this article are a summary of the income and expenses associated with the farm's highly profitable crop production, the ground-water monitoring project being conducted by the Geological Survey Bureau, the woodlot rejuvenation project, soil and wildlife conservation improvements, and the prairie forbes exhibit area. The farm continues to serve as a primary source of income for the Academy and a …

Post-Natal Survival Of Raccoons In Relation To Female Age And Denning Behavior, Jonathan J. Judson, William R. Clark, Ronald D. Andrews

Journal of the Iowa Academy of Science: JIAS

We measured post-natal survival of radio-collared raccoons 1-5 months old in southwest Iowa, 1988-1989. We compared survival of young nurtured by yearling and adult females and related den site selection to survival functions using proportional hazards models. Adult females used upland and farmstead habitats note frequently than yearlings, whereas yearling females used lowland habitats note frequently. Tree cavities and beds on the ground were used most frequently. Adult females denned in buildings 13% of the time and in holes in the ground 9.5% of the time, whereas yearlings frequently tested with litters in beds on the ground (31%). Microhab1tat characteristics …

Effects Of Competition And Predation On Prothonotary Warblers And House Wrens Nesting In Eastern Iowa, Timothy Brush

Journal of the Iowa Academy of Science: JIAS

In a fragmented midwestern floodplain forest, a small Prothonotary Warbler (Protonotaria citrea) population experienced high competition with House Wrens (Troglodytes aedon) and mammalian nest predation in 1988-89. Despite the provision of 3 types of nest boxes and higher water levels, Prothonotary Warblers did not nest successfully and decreased in the fragmented forest in 1990-91. House Wrens used >90% of the nest boxes in both years. Wren territories doubled within the nestbox area, while remaining constant on an unmanipulated area. In contrast, a larger warbler population had high nesting success during 1990-91 in a relatively unfragmented, wetter forest tract. Such forests, …

Journal Of The Iowa Academy Of Science Submission Form And Instruction Sheet

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Research Papers By 1992 And 1993 Interns In The Program For Women In Science And Engineering At Iowa State University, Mary Ann Evans, Krishna S. Athreya

Journal of the Iowa Academy of Science: JIAS

The papers in this volume offer a sampling of the outstanding work of high school and undergraduate interns who participated in the 1992 and 1993 Program for Women in Science and Engineering (PWSE) summer internship programs. From synthesis of materials to developing effective methods of hazardous waste disposal, from nondestructive structural studies at the macroscopic level to microstructural analyses of materials, from testing precision of sensors used as aids in agriculture to isolating effects of specific parameters on plant growth, to name a few, these papers span a wide range of scientific methods and disciplines. They serve as testimony to …

Crystal Structure Of An Iodine Phenazine Complex: C12h9n2 + · I3-. C12h8n2 · 1/6i2, Rebecca A. Brandenburg, Sharon L. Ringrose, Robert A. Jacobson

Journal of the Iowa Academy of Science: JIAS

A structural study of the polyiodide containing species C₁₂H₉N₂⁺ I₃^- C₁₂H₈N₂ · 1/6I₂ was carried out by single crystal X-ray diffraction techniques. The material crystallizes in the monoclinic space group C2/m with a= 16.561(5), b = 8.372(2), c = 9.908(5) A and β = 111.24°. There are two molecules per cell. Dara were collected using Mo K_ἀ radiation and refinement converged to R = 0.027 based on the 1996 unique reflections with |F_o|≥3δ(F_o). The iodine atoms were found coexist in two …

Removal Of Magnetic Impurities From Strontium Copper Oxychloride, Colleen B. Eads, Carol J. Kosmicke, Lance L. Miller

Journal of the Iowa Academy of Science: JIAS

Analyses of a copper-deficient series of Strontium Copper Oxychloride polycrystalline samples are reported. Magnetic susceptibility, X-ray powder diffraction, and differential thermal analyses show a small Curie-type magnetic signal correlates with =0.6% (excess) copper ions in the nominally stoichiometric material. The analyses also imply that the extra magnetic signal is from an impurity phase, possibly related to Strontium Copper Oxide. The concentration of the impurity phase can be controlled by varying the copper stoichiometry.

Testing The Accuracy And Precision Of Wetness Sensors In A Tomato Field And On Turfgrass, Kara J. Potratz, Mark L. Gleason, Melanie L. Hockmuth, Sharon K. Parker, Glenn A. Pearston

Journal of the Iowa Academy of Science: JIAS

Measurements of dew-period duration by painted, flat-plate, electronic wetness sensors at the top of the plant canopy in a tomato field and on adjacent turfgrass were compared with visual observations. The response range of sensors during the onset of dew sometimes exceeded 5 hr. but was less than 1 hr. on other nights. Sensors in the tomato field indicated dew formation occurred as much as 2 hr. earlier or later than dew became visible on adjacent tomato leaflets at the top of the crop canopy. A calibration threshold for sensors derived from a drying curve resulted in the underestimation of …

Soybean Residual Effects On A Subsequent Maize Crop, E. S. Escuro, D. N. Sundberg, R. M. Shibles

Journal of the Iowa Academy of Science: JIAS

Maize (Zea mays 1.) grown after soybean (Glycine max 1. Merr.) consistently performs better than maize that follows itself (second year maize), irrespective of nitrogen fertilization. In previous studies of the soybean-maize rotation, there never has been an evaluation of the potentially different effects of soybean genotypes on following maize. A two-year, soybean maize rotation was initiated in Ames at 1988 with the first year planted to various soybean genotypes, a maize hybrid, and oat (Avena sativa 1.). These were followed in the second year by a single maize hybrid with 0, 80, 160, and 240 kg/ha N fertilization levels. …

Annual Report Of The Iowa Academy Of Science, 1993-94, Paul E. Rider

Journal of the Iowa Academy of Science: JIAS

Since 1976, annual reports have served as a continuing record of the activities of the Iowa Academy of Science and an archive for its history. These augment the 100 year IAS history written in the centennial year of 1975.

This report covers the period from July 1, 1993 to June 30, 1994. It is based on the official records of the Academy (committee reports, Board minutes, correspondence) as well as the recollections, impressions and thoughts of the author.

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Use Of Ion Exchange Membranes For Selective Recovery Of Aspergillus Awamori Glucoamylase And Phage T4 Lysozyme, Deborah K. Stafslein, Jeff M. Hunter, Craig E. Forney

Journal of the Iowa Academy of Science: JIAS

Our research examined whether enhanced separation and purification of mutant enzymes could be obtained on ion-exchange membranes. Solutions of three mutants of Aspergillus awamori glucoamylase were passed through an anionic exchange membrane, as well as one mutant of T4 lysozyme through a cationic exchange membrane. The mutant enzymes were modified by adding "charged fusions'', polypeptides of either aspartic acid residues to increase the overall negative charge of the enzyme or arginine residues to increase the overall positive charge. The effect of the mutations on the purification of glucoamylase from a "modified" fermentation broth were examined at two different elution pHs, …