Physical Sciences and Mathematics Commons^™

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.

Results Of The August Roadside Survey For Upland Wildlife In Iowa: 1963-1988, Willie J. Suchy, Ronald J. Munkel, James M. Kienzler

Journal of the Iowa Academy of Science: JIAS

Results of the August roadside survey collected from 1963 through 1988 were examined to determine if trends could be detected in the counts of ring-necked pheasants (Phasianus colchicus), northern bobwhite (Colinus virginianus), gray partridge (Perdix perdix), cottontail rabbits (Sylvilagus floridanus), and white-tailed jackrabbits (Lepus townsendii). The counts also were compared to harvest estimates co determine if correlations exist. Statistically significant linear trends were detected statewide for pheasants, gray partridge and jackrabbits during the 1963 co 1988 period. Trends were downward for all species except gray partridge. During the late 12 years (1977 through 1988), the only significant trend detected was …

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.

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Journal of the Iowa Academy of Science: JIAS

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Journal of the Iowa Academy of Science: JIAS

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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 …

A Study Of Sphacelotheca Occidentalis, Cause Of Kernel Smut Of Big Bluestem, Karen M. Snetselaar, Lois H. Tiffany

Journal of the Iowa Academy of Science: JIAS

Sphacelotheca occidentalis causes kernel smut disease of Andropogon gerardii, a prairie grass. The smut fungus is systemic, perennial, causes severe stunting, and sporulates in florets. Spores develop in gall-like sari composed of grass and fungal cells. Spores initiate in a meristematic area near the base of the sorus, and progressively more mature spores are found toward the sorus rip. The cylindrical sari have a central columella of host vascular tissue permeated by hyphae, sporogenous hyphae and developing teliospores that surround the columella, and a peridium of host and fungal cells. Sporogenous hyphae ramify in a gelatinous matrix that disappears as …

Comparison Of Dinitrogen Fixation And Nitrogen Transfer Potentials Of Four Red Clover Cultivars, D. E. Farnham, A. P. Mallarino, W. F. Wedin, I. T. Carlson

Journal of the Iowa Academy of Science: JIAS

The capacity to fix atmospheric N₂ and thus reduce the use of N fertilizer is an important reason for including legumes in forage mixtures. Selection for more efficient N₂ fixation could improve red clover (Trifolium prateme L.) (RC) production and its contribution to soil fertility. An isotope dilution study was conducted in two greenhouse experiments to compare the N₂ fixation and N transfer potentials of three commercial and one experimental RC cultivars. The experimental cultivar APR-8701 was selected for traits related to increased N₂ fixation (rate of acetylene reduction, root size and branch number, and nodule …

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 …

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

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Journal of the Iowa Academy of Science: JIAS

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Annual Report Of The Iowa Academy Of Science, 1989-90, Paul E. Rider

Journal of the Iowa Academy of Science: JIAS

Starting in 1976, annual reports have served as a continuing record of the activities of the Iowa Academy of Science. These augment a 100 year history of the Academy which was written in the centennial year of 1975.

This report covers the period from July 1, 1989 to June 30, 1990. It is based on the official records of the Academy (committee reports, Board minutes, correspondence) as well as the recollections, impressions and musings of the author.

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

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Journal of the Iowa Academy of Science: JIAS

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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. …

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 …

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Middle Woodland Field Camps In The Cedar Valley, Michael J. Perry

Journal of the Iowa Academy of Science: JIAS

Archaeological survey and testing of two proposed road projects within the Cedar River valley resulted in the location of several prehistoric occupational sites. Ceramics recovered at three of the sites, 13LN226, 13LN236, and 13LN243, are identified as late Middle Woodland period specimens, dating to ca. A.D. 200. The three sites border Cedar River tributaries, occupying high terrace formations within the broad bottomlands of the Cedar valley. The type and distribution of artifacts suggest that 13LN236 and 13LN243 functioned as repeatedly utilized, short-term extractive and processing camps. Previous research at sites of similar age focused on small, protected rockshelters and large, …

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 …

Comparison Of Mass Selection And S1 Testing Recurrent-Selection Methods In Sorghum, R. E. Secrist, R. E. Atkins

Journal of the Iowa Academy of Science: JIAS

Mass selection and S₁ testing are often used for the improvement of sorghum [Sorghum bicolor (L.) Moench] populations. Both recurrent selection methods have a place in applied breeding programs and should be used where they are likely to be most advantageous. S₁ families of a random-mating sorghum population mass selected three cycles (C3) for individual-panicle weight [IAP1R(M)C3] were compared with S₁ families from a population (C3) advanced from the same base (CO) population by using replicated yield tests in each cycle [ IAP4R(S₁)C3]. Our objectives were to compare the performance in C3 of families developed …

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Journal of the Iowa Academy of Science: JIAS

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Journal of the Iowa Academy of Science: JIAS

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Front Matter

Journal of the Iowa Academy of Science: JIAS

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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 …

An Annotated Checklist Of The Vascular Plant Flora Of Guthrie County, Iowa, Dean M. Roosa, Lawrence J. Eilers, Scott Zager

Journal of the Iowa Academy of Science: JIAS

The known vascular plant flora of Guthrie County, Iowa, based on field, herbarium, and literature studies, consists of 748 taxa (species, varieties, and hybrids), 135 of which are naturalized. Species which appear on the state's list of endangered and threatened species, or are otherwise rare, are discussed.

There is an affinity of the plants of Guthrie County with those of the Ozark plateau, and with specialized habitats providing extensions of ranges for species normally found farther north or east.

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

Journal of the Iowa Academy of Science: JIAS

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Journal of the Iowa Academy of Science: JIAS

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Part Ii - Regular Issue

Journal of the Iowa Academy of Science: JIAS

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The Role Of Mechanical Injury In An Experimental Transmission Of Flexibacter Columnaris To Fingerling Walleye, Manzoor Hussain, Robert C. Summerfelt

Journal of the Iowa Academy of Science: JIAS

The role of mechanical injury in transmission of Flexibacter columnaris to walleye fingerlings (Stizostedion vitreum vitreum) was investigated. Two groups (1 and 2) of 10 fish each, 7 to 9 cm total length, were exposed to a suspension of F lexibacter columnaris containing 3 X 105 cfu/ mL; fish in group 1 were injured with a scratch along their flank; fish in group 2 were not injured. Two control groups (3 and 4) of 5 fish each were exposed to a sterile broth; group 3 was injured with a scratch and group 4 was not. In 72 h, morbidity was …