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Index To Volume 28

Iowa Science Teachers Journal

No abstract provided.

Radon In Iowa Homes: Results Of Screening Measurements, Laurent Hodges, Lynne Gillette

Journal of the Iowa Academy of Science: JIAS

Homeowner-initiated short-term radon screening measurements in Iowa homes show that only about 30% of the homes have low enough radon levels - below 148 Bq/m (4.0 pC1/L) - that no follow-up measurements are necessary. Over 6 percent of the homes have screening measurements in excess of 740 Bq/m³ (20 pCi/L), a level at which prompt follow-up measurements are recommended. In all parts of the state, the range of radon results extends from low levels (below 37 Bq/m³ = 1 pCi/L) to high levels (above 740 Bq/m³). The average radon results tend to be higher than the …

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Auxin-Regulated Gene Expression, Tom J. Guilfoyle

Journal of the Iowa Academy of Science: JIAS

A number of cDNA clones to independent mRNAs that increase in amount after brief exposure to auxins have been isolated. From soybean, sequenced, and characterized. Increases in mRNA abundance can be detected as early as 2.5 minutes after auxin application to excised elongating regions of soybean hypocotyls. Increased transcription rates on the genes which encode the auxin-responsive mRNAs account, at least partly, for the accumulation of mRNAs. A variety of auxins induce the accumulation of the mRNAs, but other plant hormones have no effect on the mRNA abundance. Some of the genes which encode the mRNAs are clustered in the …

Hormonal Regulation Of Gene Expression M The Aleurone Layers Of Cereal Grains, Tuan-Hua David Ho

Journal of the Iowa Academy of Science: JIAS

The aleurone layers of cereal grains offer a convenient system for studies of the molecular action of two plant hormones, gibberellins (GA) and abscisic acid (ABA). Gibberellins induce the synthesis of ix-amylase and several other hydrolytice enzymes. The action of GA is essentially at the transcriptional level, it enhances the level of steady-state levels of ix-amylase mRNAs, the rate of transcription of ᴕ-amylase genes and the activity of a trans-acting factor which interacts with specific regions of ix-amylase genes. Abscisic acid antagonizes the effect of GA by inhibiting the induction of hydrolytic enzymes, yet the effect of ABA itself is …

The Future Of Lasers And Laser Applications, William C. Stwalley

Journal of the Iowa Academy of Science: JIAS

Lasers are increasingly used in· an astounding variety of scientific, engineering, medical and commercial applications. Here the prospective improvements in lasers will first be addressed, e.g., improvements in wavelength range, tunability, pulse duration, efficiency, cost, etc.

Laser applications will then be briefly surveyed, including selected topics involving basic research, materials processing, analytical and diagnostic applications, information transmission and storage, measurement and alignment and photochemical and biomedical application.

Relative Abundance Of Eastern Screech-Owls In A South-Central Iowa Township, David E. Geus, John B. Bowles

Journal of the Iowa Academy of Science: JIAS

Roadside playback surveys of Eastern Screech-Owls were conducted each spring and fall from September 1984 through April 1986 in Summit Township, Marion County, Iowa. An average of 18 screech-owls were located during each survey, often near riparian woodland. Screech-owl population densities (0.1-0.2 owls/km²) were comparable to those in other regions.

Lxodes Dammini (Acari, Ixodidae) And Borrelia Burgdorferi In Iowa, Mark G. Novak, Wayne A. Rowley, Kenneth B. Platt, David M. Bartholomew, Michelle D. Senne

Journal of the Iowa Academy of Science: JIAS

A statewide study to evaluate the presence, distribution and abundance of the deer tick, Ixodes dammini, and the spirochete, Borrelia burgdorfen, in Iowa was initiated in 1989. Six hundred and seventy-one tick collections were received from health professionals, conservation employees and concerned citizens. Additional ticks were obtained by flagging, small mammal trapping and deer checks in selected areas of Iowa. Nine I. dammini were collected in 1989 from seven counties in the eastern half of the state. Six of these were tested for B. burgdorferi and all were negative. Flagging, small mammal trapping and deer checks in eastern Iowa failed …

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Solid Substrate Room-Temperature Phosphorescence Of Phenothiazine And Related Compounds, William D. Savage, Ronald T. Pflaum, Catherine Hinga Haustein

Journal of the Iowa Academy of Science: JIAS

The room-temperature phosphorescence characteristics of phenothiazine, phenothiazine-based pharmaceuticals, and related compounds are presented. It was found that substitution onto the parent ring produces little variation in RTP excitation and emission wavelengths, but electron withdrawing substituents reduce RTP intensity. Procedures for the determination of procaine and promethazine in urine and clorpromazine in whole blood are presented.

Genetic Variation Among And Within S1 Progenies Of Maize, R. J. Getschman, A. R. Hallauer

Journal of the Iowa Academy of Science: JIAS

Inbred line development consumes a great portion of the breeder's time and resources in maize (Zea mays L.) breeding programs. Source populations for line development often are developed by selfing F2 populations developed from elite line crosses. Visual selection is practiced among and within selfed progenies during the selection process for one or two generations before evaluated in testcrosses for combining ability. Effective discrimination among and within inbred and testcross progenies depends on the amount of genetic variation present. The objective of this study was to determine the effectiveness of selection among and within S₁ progenies developed from crosses …

Area-Dependent Changes In Bird Densities In Iowa Marshes, Mike Brown, James J. Dinsmore

Journal of the Iowa Academy of Science: JIAS

Species richness and density of Iowa marsh birds were positively correlated with marsh area, but area accounted for 69% of the variation in species richness and only 19% of the variation in density. Although densities of five of nine species examined correlated with marsh area, total density was not significantly correlated with area when the effects of species richness were eliminated. Area was the most frequent significant variable in regression equations for species richness, total density, and the densities of nine individual species on six variables. Unlike species-area relationships, density-area relationships are relatively weak, and knowledge of other ecological factors …

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Heating Degree Days In Iowa Relative To Home Natural Gas Consumption, Conservation Efforts, And Long-Term Trends, Richard E. Carlson

Journal of the Iowa Academy of Science: JIAS

A methodology is presented to assess the effectiveness of conservation efforts relative to home heating. Billing period heating degree days and natural gas consumption relationships are established for a typical household for nineteen heating seasons using simple linear regression. Associated correlations (r² values) were greater than 0. 95 for nineteen different seasons. Regression coefficients (b₀ and b₁) were found to decrease with time indicating reduced natural gas consumption due to conservation efforts. Procedures are presented to illustrate dollar savings relative to conservation efforts using the regression relationships. Long-term trends for heating degree days at the Ames, …

Food Habits Of The Northern Saw-Whet Owl In Central Iowa: Effects Of Roost Location, Stephen J. Dinsmore, William R. Clark

Journal of the Iowa Academy of Science: JIAS

During the period 1979-89, 900 northern saw-whet owl (Aegolius acadicus) pellets with identifable remains of prey were collected at 18 central Iowa locations. Peromyscus were the most frequent prey consumed, comprising 81.2% of all prey items. Other prey species were voles (Microtus), western harvest mice (Reithrodontomys megalotis), shrews (Blarina brevicauda, Sorex cinereus, and Cryptotis parva), and a single unidentified bird. Peromyscus comprised the largest proportion of pellets from different successional stages. There were significant differences for four prey groups (Peromyscus, Microtus, Reithrodontomys, and shrews) among years. Peromyscus and R. megalotis showed significant differences among locations. Microtus and shrews were variable …

Studies Of The Precambrian Geology Of Iowa: Part 3. Geochronologic Data For The Matlock Drill Holes, W. R. Van Schmus, E. T. Wallin

Journal of the Iowa Academy of Science: JIAS

U-Pb ages have been determined for quartz monzodiorite (2,535 ± 5Ma) recovered from drill hole ClO and for keratophyre (1,782±10 Ma) recovered from drill hole C5 of the Matlock exploration project. Sm-Nd whole-rock analyses for several rock types from the Otter Creek layered mafic complex recovered from several drill holes of the Matlock project yield an isochron age of 2,890 ± 90 Ma, with an ϵNd(t) of -0.9 ± 2.4. These ages document crustal evolution in northwest Iowa, including the southern margin of the Superior Province, over more than one billion years from 2.9 to 1.8 Ga. Isotopic data also …

Comprehensive Examination In Physics, Timothy Cooney

Iowa Science Teachers Journal

The following exam has been developed over several years of physics teaching and research. It is designed to serve as the comprehensive final exam for graduating seniors completing physics at Northern University High School in Cedar Falls, Iowa.

Astronomy Bulletin - The 1991 Summer Sky, P. Steven Leiker

Iowa Science Teachers Journal

No abstract provided.

Science Notes - Program For Leadership In Earth Systems Education Workshops

Iowa Science Teachers Journal

The Program for Leadership in Earth Systems Education (PLESE) has announced its 1992 Summer Workshop program. The program will serve groups of teachers at two sites, Ohio State University in Columbus and the University of Northern Colorado in Greeley.

Science Notes - Scholarships Available To Minority Students, Stephanie A. Althof

Iowa Science Teachers Journal

The American Physical Society (APS) is once again offering "Corporate Sponsored Scholarships for Minority Undergraduate Students Who Major in Physics."

An Inexpensive And Collapsible Plant Growth Frame, Al Janulaw, Mat Keller

Iowa Science Teachers Journal

This plant growth frame was designed for use in second and fourth grade classrooms as a part of National Science Foundation Grant TEI 8751303, Materials and Assistance for Science Teaching (MAST). We needed frames that were relatively inexpensive, could be made from locally available materials and would be easy to store when not in use. The frame is made from PVC pipe. The light source is a 48-inch, two-bulb shop light, using ordinary fluorescent tubes. A plug-in timer is used to control the time of illumination. Our first models included a plywood base, but some teachers have omitted this. The …

The Iowa Science Teachers Fall Conference, 1991, Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Speakers ... 4
Pre-conference Workshops ... 6
General Session ... 9
Concurrent Sessions 1 ... 9
Concurrent Sessions 2 ... 13
Application for Membership ... Centerfold
Registration Fonns ... Centerfold
Luncheon Information ... 17
Concurrent Sessions 3 ... 17
Concurrent Sessions 4 ... 21
Maps ... 25 & 26

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Back Cover

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.

Part I - Papers Presented At The 1989 Plant Science Lecture Series

Journal of the Iowa Academy of Science: JIAS

The first six titles in this issue of the Journal of Iowa Academy of Science are papers presented at the 1989 edition of the Plant Science Lecture Series held annually at Iowa State University. This lecture series focuses each year on some aspect of plant biology, and each series is composed of six to eight seminars related to a theme that is selected to be timely and related to improvement of field, forage, forest and horticultural crops.

Regulation Of Phytochrome Gene Expression, J. T. Colbert, S. A. Costigan, P. Avissar, Z. Zhao

Journal of the Iowa Academy of Science: JIAS

In etiolated oat seedlings exposure to red light results in a decrease in the transcription of the phytochrome genes, the abundance of phytochrome mRNA, and the level of phytochrome protein. Phytochrome itself serves as the photoreceptor for the response of decreased mRNA and transcription levels. The decrease in phytochrome mRNA is sensitive to low levels of Pfr. Even green "safelight" is capable of inducing a decrease in phytochrome mRNA abundance. Barley phytochrome mRNA abundance is also dramatically down-regulated in response to red light but other plant species vary in their ability to decrease phytochrome mRNA abundance after red light treatment. …

The Axr1 Mutation Of Arabidopsis Is Expressed 10 Booth Roots And Shoots, Cythia Lincoln, Mark Estelle

Journal of the Iowa Academy of Science: JIAS

In order to identify genes involved in auxin action we have isolated a number of mutants of Arabidopsis thaliana which are resistant co exogenous application of either indole-3-acetic acid or 2, 4-dichlorophenoxyacecic acid. One of the genes identified in chis way is the Axr1 gene. Recessive mutations in this gene confer resistance co auxin as well as a number of morphological defects. In this report we describe the isolation of at least two new axr1 alleles. In addition, we show that the axr1 mutation affects gravitropic growth of the root, auxin-induced ethylene biosynthesis and growth in tissue culture. Our results …

Part Ii - Regular Issue

Journal of the Iowa Academy of Science: JIAS

No abstract provided.