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Full-Text Articles in Science and Mathematics Education

Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1988

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Cover - Table Of Contents Jan 1988

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Evaluation Of Fish Eradication And Game-Fish Restocking In A Central Iowa Pond, Dennis L. Scarnecchia Jan 1988

Evaluation Of Fish Eradication And Game-Fish Restocking In A Central Iowa Pond, Dennis L. Scarnecchia

Journal of the Iowa Academy of Science: JIAS

Changes in fish community and population structure associated with fish eradication and subsequent restocking were investigated in a small (0. 25 ha) impoundment in Boone County, Iowa. In September 1985, when fish were eradicated with rotenone, the fish community consisted of eight species. Large numbers of small bluegills (Lepomis macrochirus), green sunfish (Lepomis ryanellus), and stunted crappies (Pomoxis spp.) dominated the pond numerically, but seven large carp (Cyprinus carpio) and 18 large bigmouth buffalo (lctiobus ryprinellus) constituted 80% of the total biomass. The only quality angling (popular species of desirable size) was for a few largemouth bass (Micropterus salmoides) and …


Solvent Effects In Room Temperature Phosphorescence, Shane J. Helsenbeck, Catherine Haustein Jan 1988

Solvent Effects In Room Temperature Phosphorescence, Shane J. Helsenbeck, Catherine Haustein

Journal of the Iowa Academy of Science: JIAS

Room temperature phosphorescence (R TP) analysis is a technique in which solutions containing organic phosphors are applied to filter paper and dried in the absence of oxygen. Adsorption to the paper inhibits molecular vibrations and promotes phosphorescence. Although the solvent must be removed by volatilization before phosphorescence can occur, it appears that the nature of the solvent affects the intensity of the resulting phosphorescence. We examined the room temperature phosphorescence of p-aminobenzoic acid which had been dissolved in water, organic solvents, or mixtures of water and organic solvents. It was found that solvent volatility had little correlation with RTP intensity …


Back Cover Jan 1988

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Using Life History And Ecology As Tools To Manage A Threatened Salamander Species, Scott R. Mcwilliams, Marilyn D. Bachmann Jan 1988

Using Life History And Ecology As Tools To Manage A Threatened Salamander Species, Scott R. Mcwilliams, Marilyn D. Bachmann

Journal of the Iowa Academy of Science: JIAS

Selected aspects of the life history and ecology of the small-mouthed salamander (Ambystoma texanum Matthes) relevant to the management of this threatened species in Iowa are presented. The population studied utilizes flooded woodland habitat during courtship, breeding and egg laying, and during the entire larval period. Larval foraging strategies in this habitat included ontogenetic but no diel shifts in prey selection. Synchronous, nocturnal breeding migration allowed effective use of drift fences fur capture of adults used in captive breeding, courtship behavior studies, and the estimation of breeding population size. Large numbers of spennatophores, apparently indiscriminate mate choice, and the relatively …


Soil N Availability And Nitrogen Harvest Index Of Oats, N. Md. Kairudin, K. J. Frey Jan 1988

Soil N Availability And Nitrogen Harvest Index Of Oats, N. Md. Kairudin, K. J. Frey

Journal of the Iowa Academy of Science: JIAS

A population of 480 random lines of oats (Avena sativa L.) was grown on soil that received no application of nitrogen (N) or 112 kg of N ha-1 (defined as low- and high-N environments, respectively) to evaluate the effect of N availability in the soil on the plant's ability to partition N between vegetative tissue and the grain, a ratio defined as nitrogen harvest index. Also, comparisons were made between low and high-N environments for grain yield, straw yield, biological yield, groat protein yield, groat protein percentage, vegetative protein yield, straw protein percentage, total plant protein yield, and harvest …


Cover - Table Of Contents Jan 1988

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Journal Of The Iowa Academy Of Science Submission Form And Instruction Sheet Jan 1988

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

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Seasonal Composition Of Benthic Diatom Associations In The Cedar River Basin (Iowa), Stephen P. Main Jan 1988

Seasonal Composition Of Benthic Diatom Associations In The Cedar River Basin (Iowa), Stephen P. Main

Journal of the Iowa Academy of Science: JIAS

This is the first detailed report on the taxonomy and ecology of diatoms in the portion of the upper reaches of the Cedar River basin in Iowa. This paper describes the diatom taxa from shallow benthic substrata collected quarterly between 11 October 1975 and 19 February 1977 at 14 sampling stations. Just over 500 frustules were counted from each of the 216 samples obtained. Analysis of water samples collected at the same time as the diatoms indicates these screams have alkaline hard waters rich in nutrients with extreme turbidity level fluctuation at irregular intervals.

The 281 diatom taxa identified represented …


Reevaluating Evidence For The Pre-Lllinoian Entrenchment Of Northeastern Iowa River Valleys, Curtis M. Hudak Jan 1988

Reevaluating Evidence For The Pre-Lllinoian Entrenchment Of Northeastern Iowa River Valleys, Curtis M. Hudak

Journal of the Iowa Academy of Science: JIAS

Previous workers have proposed a pre-Illinoian age for the deepest bedrock entrenchment of northeastern Iowa valleys. Lines of evidence used to support a pre-Illinoian age of entrenchment are: (1) deep bedrock-entrenchment interpreted to take "long" periods of time, (2) "valleys" filled with "red-weathered drift", which was interpreted as "old", (3) differences in cross-valley profiles supposedly related to glacial advances, (4) thick beds of gravel could only be deposited by outwash streams, and (5) glacially buried (drift-filled) bedrock valleys exist outside of the Paleozoic Plateau to the west and south. These inferences are questionable because: ( 1) erosion (entrenchment) rates are …


The Status Of Three Uncommon Salamanders (Amphibia: Caudata) In Iowa, Jeffery D. Camper Jan 1988

The Status Of Three Uncommon Salamanders (Amphibia: Caudata) In Iowa, Jeffery D. Camper

Journal of the Iowa Academy of Science: JIAS

The smallmouth salamander [Ambystoma texanum (Matthes)], blue-spotted salamander (Ambystoma laterale Hallowell), and central newt [Notophthalmus viridescens louisianensis (Wolterstorff)] were studied in Iowa from fall 1982 through summer 1984. All three species have declined in abundance in Iowa. A. texanum is more abundant and widespread than was previously suspected, but is declining due to habitat destruction. Apparently, only two populations of A. laterale remain in Iowa. N. v. louisianensis has also declined due to habitat destruction, with only three populations known. All three species require ponds in or adjacent to forest. A. ta was found primarily in riparian …


Cover - Table Of Contents Jan 1988

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Front Matter Jan 1988

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


An Interpretative History Of The Proceedings Of The Iowa Academy Of Science, Don C. Norton Jan 1988

An Interpretative History Of The Proceedings Of The Iowa Academy Of Science, Don C. Norton

Journal of the Iowa Academy of Science: JIAS

The Proceedings of the Iowa Academy of Science was first published in 1887 and has continued yearly except for 1905. Business reports and contributed papers constituted most of the volumes. Publication of symposia has become more popular in recent years. Financial and mechanical problems have caused strains at rimes, but these have largely been solved after publication became independent of the State Printer.


Predation By Ermine And Long-Tailed Weasels On Duck Eggs, Joseph P. Fleskes Jan 1988

Predation By Ermine And Long-Tailed Weasels On Duck Eggs, Joseph P. Fleskes

Journal of the Iowa Academy of Science: JIAS

Ermine (Mustela erminea) and long-tailed weasel (M. frenata) predation on duck eggs was studied at Union Slough National Wildlife Refuge, Kossuth County, Iowa, 1984-85. Captive individuals of both species ate 2-4 duck eggs at a rate of 0.5-2 eggs per trial day. All eggs were moved but some were not opened. One hole, ringed with small fragments and "bite-outs'', was made in all eggs opened by captive weasels. In the field, the appearance of opened eggs, the pattern of egg loss and the amount of nest bowl disturbance were used to determine the number of nests depreciated by weasels. Egg …


Biotechnology: Impact On Iowa's Agricultural Economy, Dwight T. Thomas Jan 1988

Biotechnology: Impact On Iowa's Agricultural Economy, Dwight T. Thomas

Journal of the Iowa Academy of Science: JIAS

Agriculture has always been an important cornerstone of Iowa's economy. The highly publicized difficulties in the agricultural economy in Iowa have highlighted both the importance of agriculture and pitfalls when agriculture is hit by adverse conditions. Iowa's agriculture and agricultural infrastructure have a heritage characterized by the development of very efficient production technology and the early use of innovative ideas. The early adoption of hybrid corn is but one example of the acceptance new technology. Today more than ever before there is a need for improved profitability and for the possibility of diversification of agricultural products in Iowa.

The following …


Program Abstracts, 100th Session, Iowa Academy Of Science, April 21-23, 1988, Iowa State University Jan 1988

Program Abstracts, 100th Session, Iowa Academy Of Science, April 21-23, 1988, Iowa State University

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Economic Changes From The Use Of Biotechnology In Production Agriculture, Loren W. Tauer Jan 1988

Economic Changes From The Use Of Biotechnology In Production Agriculture, Loren W. Tauer

Journal of the Iowa Academy of Science: JIAS

The potential economic impact of biotechnology in production agriculture is discussed. There are challenges and difficulties in completing economic research when little production information is available on biotechnologies. I argue that little impact differences exist between cost-reducing versus output-increasing technological change. Rapid technological change results in low average returns in agriculture but continuous early innovators earn higher returns. Various plant and animal technologies are presented and discussed.


Back Cover Jan 1988

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Front Matter Jan 1988

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Dr. James G. Macmillan, Executive Director, Iowa Academy Of Science, 1983-1988 Jan 1988

Dr. James G. Macmillan, Executive Director, Iowa Academy Of Science, 1983-1988

Journal of the Iowa Academy of Science: JIAS

The officers and Board of Directors of the Iowa Academy of Science dedicate this issue of the Journal of the Iowa Academy of Science to Jim Macmillan in recognition of his five years of exemplary leadership. During this period, Jim's managerial expertise has served the Academy well and membership has grown significantly. Under Jim's guidance the Academy has improved its financial base through sound fiscal policies, and important steps have been taken in the area of computerized record keeping and data management.


Benthic Macroinvertebrate Habitat Associations Of The Channelized Middle Missouri River, James B. Barnum, Roger W. Bachmann Jan 1988

Benthic Macroinvertebrate Habitat Associations Of The Channelized Middle Missouri River, James B. Barnum, Roger W. Bachmann

Journal of the Iowa Academy of Science: JIAS

Benthic macroinvertebrates associated with navigation structures (dikes, dike pools, revetted banks) and abandoned channels on the Missouri River at the Iowa-Nebraska border were sampled in June, August, and October 1983 to determine the invertebrate community structure of these habitats. Invertebrate densities were greatest in the abandoned channel habitat (to over 13,000/m2), while diversities were greatest in the dike and revetment habitats. Greater habitat diversity contributed to greater organism diversity in the dike and revetment habitats while sediment homogeneity and stability presumably contributed to greater organism densities in the abandoned channel habitat. Dike pools had turbulent eddy currents, which …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1988

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Some Genetic Characteristics Of Three Walleye Stocks In Iowa And The Impact Of Fry Stockings In The Cedar River, Vaughn L. Paragamian Jan 1988

Some Genetic Characteristics Of Three Walleye Stocks In Iowa And The Impact Of Fry Stockings In The Cedar River, Vaughn L. Paragamian

Journal of the Iowa Academy of Science: JIAS

Fry stockings of walleye Stizostedion v. vitreum into the Cedar River, Iowa began in the early 1950's, and two studies of the success of these plants gave conflicting results. The objectives of my study were to identify some genetic characteristics in three stocks of walleye and to utilize these characteristics to assess the genetic impact of fry stockings in the Cedar River. Electrophoretic analysis of malate dehydrogenase (MDH) and isocitrate dehydrogenase (IDH) was completed for walleye stocks from the Mississippi and Cedar Rivers, and Big Spirit Lake, Iowa. Phenotypic frequencies of Mdh - B2 and Mdh - B3 …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1988

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Front Matter Jan 1988

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Recompact Iowa Soil Materials Before Using As Liners For Waste Containment, G. J. Kluitenberg, R. Horton, M. L. Thompson, J. F. Mcbride Jan 1988

Recompact Iowa Soil Materials Before Using As Liners For Waste Containment, G. J. Kluitenberg, R. Horton, M. L. Thompson, J. F. Mcbride

Journal of the Iowa Academy of Science: JIAS

Soil materials are often used in hazardous-waste disposal facilities to provide a physical barrier to leachate movement. Both existing soils and recompacted soil materials have been used in barrier construction. Solute transport experiments and measurements of saturated hydraulic conductivity were used to characterize the solute transport properties of three Iowa soil materials. Experiments were carried out by using undisturbed soil samples as well as recompacted samples. The experimental results show that recompaction greatly altered the solute transport properties of the three soil materials. It is concluded that recompaction is necessary for any of these materials to satisfy Environmental Protection Agency …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1988

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Nebraska Summary: S031 Massey Ferguson 375, Nebraska Tractor Test Lab Jan 1988

Nebraska Summary: S031 Massey Ferguson 375, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …