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The Accuracy Of Sonographic Imaging (Dolphintm Digigraph) And Standard Lateral Cephalometric Radiographs : A Comparative Study, Michael D. Teichman Jun 1991

The Accuracy Of Sonographic Imaging (Dolphintm Digigraph) And Standard Lateral Cephalometric Radiographs : A Comparative Study, Michael D. Teichman

Loma Linda University Electronic Theses, Dissertations & Projects

Radiation due to x-ray exposure is a concern, and the development of the Dolphin™ DigiGraph represents an attempt to limit this exposure. The purpose of this paper was to compare measurements (using Ricketts analysis) obtained from conventional radiographic cephalometric tracings with those obtained by computerized digitizing with the DigiGraph. Forty-six patients from the Loma Linda University School of Dentistry graduate orthodontic clinic were digitized, and the results were compared to the x-ray tracings of these patients. The results showed that seven of the twenty-one variables examined exhibited a statistical similarity between the two methods (DigiGraph and x-ray tracing). An examination …


Program Abstracts, 103rd Session, Iowa Academy Of Science, April 19-20, 1991, Iowa Academy Of Science Apr 1991

Program Abstracts, 103rd Session, Iowa Academy Of Science, April 19-20, 1991, Iowa Academy Of Science

Iowa Academy of Science Documents

Presentation abstracts from the annual meeting of the Iowa Academy of Science


The Annual Meeting Of The Iowa Academy Of Science April 19-20, 1991 [Program, 103rd Meeting], Iowa Academy Of Science Apr 1991

The Annual Meeting Of The Iowa Academy Of Science April 19-20, 1991 [Program, 103rd Meeting], Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Program Summary --- 5
General Session Speakers --- 10
Awards --- 13
Distinguished Fellow --- 13
Distinguished Iowa Scientist --- 14
Symposia Programs --- 15
Poster Session --- 18
Campus Map --- Centerfold
Section Programs --- 19
Agricultural Sciences --- 20
Anthropology --- 21
Botany --- 21
Cellular & Molecular Biology --- 23
Chemical Education --- 27
Chemistry, Inorganic --- 27
Chemistry, Organic --- 29
Conservation --- 31
Earth Science Teaching --- 32
Elementary Science Teaching --- 32
Engineering --- 32
Geology --- 35
Linguistics --- 37
Nursing --- 38
Physics --- 38
Physiology --- 39
Psychology --- 40 …


Santa Clara Magazine, Volume 33 Number 3, Spring 1991, Santa Clara University Apr 1991

Santa Clara Magazine, Volume 33 Number 3, Spring 1991, Santa Clara University

Santa Clara Magazine

12 - ABORTION : NO SIMPLE ANSWERS Jesuit theologian Ted Mackin examines pro-life and pro-choice positions and reports that neither side is addressing the issue with total honesty. By Theodore J. Mackin, S.J.

16 - STAY AT HOME MOMS Alumnae discuss why they decided to devote all their time and attention to their families. By Michelle Burget Fletcher '78, Brigid Modena Benham '81, and Anne Penoyer King '69

20 - SCU's WINE FAMILIES Northern California's vineyards are fertile ground for Santa Clara graduates. By Rosina Wilson

28 - WORKING THE SUICIDE HOTLINE Within these walls, no secret is too terrible …


Flotation Data Sampling Strategies In Archaeological Research: An Experiment At The Elam Site (20ae195), Allegan County, Michigan, Brian David Deroo Apr 1991

Flotation Data Sampling Strategies In Archaeological Research: An Experiment At The Elam Site (20ae195), Allegan County, Michigan, Brian David Deroo

Masters Theses

Studies of prehistoric Native American subsistence patterns have benefited greatly from data recovered through the technique of flotation, which allows investigators to recover small scale organic remains which would otherwise be missed using standard excavation procedures. Using data recovered through flotation researchers have been able to more fairly evaluate the role of plant foods, both wild and cultivated, in the aboriginal diet.

A common method of obtaining a flotation sample is to define a column through the center of the cultural feature or midden and removing a specified volume of soil matrix (usually 10 liters) from this column. This thesis …


The Paleoethnobotany Of Schwerdt (20ae127): An Early Fifteenth Century Encampment In The Lower Kalamazoo River Valley, Gregory R. Walz Apr 1991

The Paleoethnobotany Of Schwerdt (20ae127): An Early Fifteenth Century Encampment In The Lower Kalamazoo River Valley, Gregory R. Walz

Masters Theses

Carbonized macrobotanical remains from the Schwerdt Site, an Upper Mississippian sturgeon fishery in the Lower Kalamazoo River Valley are identified and analyzed in terms of their implications for localized subsistence-settlement systems operating during the Berrien Phase in southwestern Michigan. The exploitation of wild plant foods at this limited-activity, spring sturgeon fishery and the environmental composition of the site environs are reconstructed from their representation in flotation samples derived from excavated feature and midden contexts.

Botanical data indicate a strong wetland-aquatic orientation in plant procurement, with aquatic tubers being the primary plant resource exploited at the site. Data from several sites …


Advice For Undergraduates On Special Aspects Of Writing Mathematics, Stephen B. Maurer Mar 1991

Advice For Undergraduates On Special Aspects Of Writing Mathematics, Stephen B. Maurer

Mathematics & Statistics Faculty Works

There are several guides to good mathematical writing for professionals, but few for undergraduates. Yet undergraduates who write mathematics papers need special guidance. For instance, professionals may need help writing clear definitions, but at least they know why explicit definitions are needed and know the basic format. In general, mathematics has many special formats that are not mere technical conventions but instead serve important purposes. Often students are not conscious of these conventions, and they rarely know their purposes. This paper contains a guide for students written in light of these observations.


Back Cover Jan 1991

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Index For Volume 98 Jan 1991

Index For Volume 98

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1991

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Studies Of The Precambrian Geology Of Iowa: Part 2. The Matlock Keratophyre, Kenneth E. Windom, Karl E. Seifert, Raymond R. Anderson Jan 1991

Studies Of The Precambrian Geology Of Iowa: Part 2. The Matlock Keratophyre, Kenneth E. Windom, Karl E. Seifert, Raymond R. Anderson

Journal of the Iowa Academy of Science: JIAS

Felsic pyroclastic rock occurs in the Precambrian basement in northwestern Iowa. This rock was recovered by drilling and originally logged as rhyolite; however it is severely depleted in K2O, Rb, Ba, Cs, and other mobile elements and is more properly called keratophyre. The volcanic unit lies atop a layered mafic/ultramafic complex and contains xenoliths of gabbro apparently derived from the layered body. These xenoliths are severely altered and are composed of secondary hydrated and carbonated minerals. The gabbros are enriched in incompatible trace elements, whose abundance patterns complement those of the keratophyre. Trace element abundance patterns for the …


In Search Of A Gibberellin Receptor, Lalit M. Srivastava, Konrad A. Sechley Jan 1991

In Search Of A Gibberellin Receptor, Lalit M. Srivastava, Konrad A. Sechley

Journal of the Iowa Academy of Science: JIAS

Use of tritiated gibberellins ([3H] GA1, [3H] GA4) of high specific activity and purity has allowed the determination of GA-specific binding sites in several plant tissues both in vivo and in vitro. In cucumber hypocotyls and pea epicotyls which have been most investigated the binding of [3H] GA; occurs to soluble proteins. This binding is saturable ('n' =about 30 pmol. Mg-1 soluble protein), of high affinity (KD= about 70 nM), and is competed for by other GA, and derivatives in proportion to their biological activity in these …


Student Fact Book, Fall 1991, Wright State University, Office Of Student Information Systems, Wright State University Jan 1991

Student Fact Book, Fall 1991, Wright State University, Office Of Student Information Systems, Wright State University

Wright State University Student Fact Books

The student fact book has general demographic information on all students enrolled at Wright State University for Fall Quarter, 1991.


Mariculture Management For Pohnpei State, Federated States Of Micronesia, Kevin Brooks Foster Jan 1991

Mariculture Management For Pohnpei State, Federated States Of Micronesia, Kevin Brooks Foster

Marine Affairs Theses and Major Papers

The Marine Resources Division of Pohnpei State, Federated States of Micronesia is currently engaged in development activities that include the establishment of family scale mariculture projects for community members of remote villages and outer islands. The goal of this undertaking is to supplement subsistence and income generation ventures for community members through the wise use and exploitation of the marine environment. These aims may be jeopardized unless a management plan is devised that reflects the customary marine resource practices as embraced by islanders from each community. The intent of this thesis projects is to devise a mariculture management model that …


Ua56/1 Fact Book, Wku Institutional Research Jan 1991

Ua56/1 Fact Book, Wku Institutional Research

WKU Administration Documents

Statistical and demographic profile of WKU.


Stimulus Response Coupling In Auxin Action, K. R. Libbenga Jan 1991

Stimulus Response Coupling In Auxin Action, K. R. Libbenga

Journal of the Iowa Academy of Science: JIAS

This paper not available at time of printing.


Back Cover Jan 1991

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Modeling Age-Specific Mortality For Marine Mammal Populations, Jay Barlow, Peter Boveng Jan 1991

Modeling Age-Specific Mortality For Marine Mammal Populations, Jay Barlow, Peter Boveng

United States Department of Commerce: Staff Publications

A method is presented for estimating age-specific mortality based on minimal information: a model life table and an estimate of longevity. This approach uses expected patterns of mammalian survivorship to define a general model of age-specific mortality rates. One such model life table is based on data for northern fur seals (Callorhinus ursinus) using Siler’s (1979) 5-parameter competing risk model. Alternative model life tables are based on historical data for human females and on a published model for Old World monkeys. Survival rates for a marine mammal species are then calculated by scaling these models by the longevity …


Iowa Academy Of Science Directory, 1991-92: Officers, Committees, And Membership Roster, Iowa Academy Of Science Jan 1991

Iowa Academy Of Science Directory, 1991-92: Officers, Committees, And Membership Roster, Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Board of Directors ... 5
Program Directors ... 6
Editors ... 6
Committees ... 8
Sections ... 21
Awards of Merit ... 26
Excellence in Science Teaching Awards ... 28
Past Presidents ... 30
Membership Roster ... 31


Front Matter Jan 1991

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Journal Of The Iowa Academy Of Science Submission Form And Instruction Sheet Jan 1991

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

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Annual Report Of The Iowa Academy Of Science, 1989-90, Paul E. Rider Jan 1991

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.


Comparison Of Mass Selection And S1 Testing Recurrent-Selection Methods In Sorghum, R. E. Secrist, R. E. Atkins Jan 1991

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 …


Estimates Of Quantitative Genetic Parameters M Iap2b(M) Random-Mating Sorghum Population, A. J. Maves, R. E. Atkins Jan 1991

Estimates Of Quantitative Genetic Parameters M Iap2b(M) Random-Mating Sorghum Population, A. J. Maves, R. E. Atkins

Journal of the Iowa Academy of Science: JIAS

Random-mating populations of sorghum [Sorghum bicolor (L.) Moench] are used extensively as germ plasm in the development of parental lines for hybrids. Populations improved by recurrent selection provide a useful source for the selection of superior parental lines. Our objective was to determine the effectiveness of mass selection for threshed-panicle weight by comparing the performance of lines (S1 families) chosen randomly from CO and C4 of sorghum population IAP2B. Sixty S1 families from each cycle were grown in five Iowa environments.

Four cycles of selection for panicle weight shifted the mean for grain yield favorably, and the range …


Radon In Iowa Homes: Results Of Screening Measurements, Laurent Hodges, Lynne Gillette Jan 1991

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 Jan 1991

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Front Matter Jan 1991

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Hormonal Regulation Of Gene Expression M The Aleurone Layers Of Cereal Grains, Tuan-Hua David Ho Jan 1991

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 Jan 1991

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 Jan 1991

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.