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Center For Sustainable Agricultural Systems Newsletter, January/February 1993 Jan 1993

Center For Sustainable Agricultural Systems Newsletter, January/February 1993

Center for Sustainable Agricultural Systems: Newsletter (1993–2000)

Defining Production Systems in Nebraska

Nebraska Environmental Trust Fund

Sustainable Ag Grants for Producers

National Sustainable Ag Coordinating Council

Federal Conservation Policy Is Changing

FAO Examines Education Programs on Environmental Sustainability

Research on Reducing Environmental Impacts of Livestock

In the Seminar Spotlight

Electronic Communication Is In


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1993

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Range Expansion Of The Great-Tailed Grackle In The 1900s, James J. Dinsmore, Stephen J. Dinsmore Jan 1993

Range Expansion Of The Great-Tailed Grackle In The 1900s, James J. Dinsmore, Stephen J. Dinsmore

Journal of the Iowa Academy of Science: JIAS

In 1900, the range of the Great-tailed Grackle extended north of the Mexican border only into Texas. Since then, it has expanded its range greatly. It now nests in 14 states and has strayed to an additional eight states and three Canadian provinces. Much of this expansion has occurred since 1960. Great-tails often stray far from their normal range, especially in spring. Most of these strays are single individuals. In states where they have nested, breeding birds typically reach the state a few years after the first reports of the species. Great-tailed Grackles do well in a variety of human …


Annual Report Of The Iowa Academy Of Science, 1992-93, Paul E. Rider Jan 1993

Annual Report Of The Iowa Academy Of Science, 1992-93, 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, 1992 to June 30, 1993. 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.


The Iowa Science Teachers 1993 Fall Conference, Iowa Academy Of Science Jan 1993

The Iowa Science Teachers 1993 Fall Conference, Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Luncheon Speaker ... 2-3
Exhibitor Checkoff ... 4
Raffle ... 5
Door Prizes ... 6 - 8
Housing Information ... 9
Concurrent Sessions I ... 10
Concurrent Sessions II ... 14
Concurrent Sessions III ... 19
Luncheon Information ... 24
Conference Registration Form ... Centerfold
Application for Membership ... Centerfold
Concurrent Sessions IV ... 25
Concurrent Sessions V ... 30
Corporate Sponsors ... 35
Exhibitors ... 36-37
Science Center of Iowa ... 38
Map ... 39
Acknowledgments ... 40
ISTS Officers and Regional Directors ... Inside Back Cover


Nuclear Magnetic Resonance Study Of Antigen-Antibody Complexes, Including Sequence Specific Assignments And Structural Analysis Of Neurophysin As An Antigen Model, Elisar Jamil Barbar Jan 1993

Nuclear Magnetic Resonance Study Of Antigen-Antibody Complexes, Including Sequence Specific Assignments And Structural Analysis Of Neurophysin As An Antigen Model, Elisar Jamil Barbar

Dissertations and Theses

The interaction between molecules is essential in a wide range of biological processes. A detailed knowledge of these interactions is necessary for understanding these processes. Among the systems that involve important interactions is the immune system. NMR spectroscopy has a large number of spectral parameters that were used in this work to study antibody-antigen interactions. These same parameters were also used to begin a structural analysis of a medium-sized protein, neurophysin, that has important interactions with neurohormones, and served here as a model antigen. A set of ligands differing in size and charge was designed and used to probe the …


Development Of A Hypermedia Database For The Elementary Classroom, Jane Pattison Brown Jan 1993

Development Of A Hypermedia Database For The Elementary Classroom, Jane Pattison Brown

All Graduate Projects

A hypermedia database including selected flora and fauna in Kittitas County, Washington, was developed using HyperCard software for researching information about 400+ species. students had the opportunity to use the database in school libraries and in the author's fifth-grade classroom. The database cards accessed videodisc images where available. On the basis of limited study to date, it appears that when studying the environment, student learning was enhanced by the use of database material created by the author.


A Review Of The Biology Of Giant Salvinia, J. Douglas Oliver Jan 1993

A Review Of The Biology Of Giant Salvinia, J. Douglas Oliver

Faculty Publications and Presentations

Giant salvinia (Salviniaceae) is a potentially serious aquatic weed that is native to Brazil. It has been reported in more than 20 countries, but is not established in the U.S. at this time. Mitchell and Tur (1975) reported that three years after the formation of the Kariba Reservoir in Africa, giant salvinia blanketed 21.5% or 1003 km2 of the reservoir surface area. Creagh (199111992) wrote, "A single small plant may grow to form a thick mat covering more than 100 sq. km. in just three months - choking lakes and waterways, reducing populations of aquatic plants and animals and in …


Winter 1993, Nsu Oceanographic Center Jan 1993

Winter 1993, Nsu Oceanographic Center

Currents

No abstract provided.


An Interpretive Framework For Application Performance Prediction, Manish Parashar, Salim Hariri, Tomasz Haupt, Geoffrey C. Fox Jan 1993

An Interpretive Framework For Application Performance Prediction, Manish Parashar, Salim Hariri, Tomasz Haupt, Geoffrey C. Fox

Northeast Parallel Architecture Center

Software development in parallel/distributed environment is a non-trivial task and depends greatly on the availability of appropriate support in terms of development tools and environments. Performance prediction /evaluation tools form a critical part of any software development environment as they enable the developer to visualize the effects of various design choices on the performance of the application. This paper presents an interpretive model for a source driven performance prediction framework. A prototype framework based on the proposed model has been developed for the iPSC/860 system. Numerical results obtained on this system are presented. These results confirm the potential of interpretive …


Binary Resolution In Surface Reasoning, William C. Purdy Jan 1993

Binary Resolution In Surface Reasoning, William C. Purdy

Electrical Engineering and Computer Science - Technical Reports

Intuition suggests the hypothesis that everyday human reasoning is conducted in the written or spoken natural language, rather than in some disparate representation into which the surface language is translated. An examination of human reasoning reveals patterns of inference that parallel binary resolution. But any standard implementation of resolution requires Skolemization. Skolemization would seem an unlikely component of human reasoning. This appears to contradict the hypothesis that human reasoning takes place at the surface. To reconcile these observations, this paper develops a new rule of inference, which operates on surface expressions directly. This rule is shown to produce results which …


Age, Growth, And Reproduction Of Tautog Tautoga Onitis (Labridae: Perciformes) From Coastal Waters Of Virginia, E. Brian Hostetter, Thomas A. Munroe Jan 1993

Age, Growth, And Reproduction Of Tautog Tautoga Onitis (Labridae: Perciformes) From Coastal Waters Of Virginia, E. Brian Hostetter, Thomas A. Munroe

Biological Sciences Faculty Publications

Tautog Tautoga onitis are gaining popularity in Virginia's coastal waters as a recreational and food fish. Adult tautog are seasonally abundant on inshore hard-bottom habitats (1-10 m) and inhabit offshore areas (10-75 m) year-round. Juveniles, especially newly-settled recruits, inhabit vegetated areas in shallow water (usually < 1 m). From March 1979 to July 1986, tautog were collected in lower Chesapeake Bay and nearby coastal waters to examine age, growth, and sexual maturation. Age estimates were determined from annular marks on opercle bones: 82% of the fish were age-10 or younger, 18% exceeded age-10, and 1% were age-20 or older. Marginal increment analysis revealed that annuli formed concurrent with a protracted spawning season (April-July). The von Bertalanffy growth equation, derived from back-calculated mean lengths-at-age, was l(t) = 742 [1-e-0.085 (t-1.816)]. Tautog are long-lived (25+ yr) and attain relatively large sizes (672 mm TL) slowly (K for sexes combined = 0.085). Growth rates of both sexes are similar, although males grow slightly faster (K = 0.090 vs. 0.085 for females). Maturity occurs at age-3 in both sexes. Growth rates for tautog from Virginia are similar to those reported nearly 25 years ago for tautog in Rhode Island. Growth rates for tautog are similar to those of other reef fishes, such as snappers and groupers. Habitat restriction, slow growth, great longevity, and increasing popularity by user groups may contribute to over-exploitation of this species in Virginia waters.


Dna Replication In Chloroplasts, Sabine Heinhorst, Gordon C. Cannon Jan 1993

Dna Replication In Chloroplasts, Sabine Heinhorst, Gordon C. Cannon

Faculty Publications

Chloroplasts contain multiple copies of a DNA molecule (the plastome) that encodes many of the gene products required to perform photosynthesis. The plastome is replicated by nuclear-encoded proteins and its copy number seems to be highly regulated by the cell in a tissue-specific and developmental manner. Our understanding of the biochemical mechanism by which the plastome is replicated and the molecular basis for its regulation is limited. In this commentary we review our present understanding of chloroplast DNA replication and examine current efforts to elucidate its mechanism at a molecular level.


Catecholamine Secretion In Bovine Chromaffin Cells : Influence Of Immune-Derived Factors, Zhaohui Wang Jan 1993

Catecholamine Secretion In Bovine Chromaffin Cells : Influence Of Immune-Derived Factors, Zhaohui Wang

Master's Theses

No abstract provided.


Sinkhole Excavations In Peccary Cave, Newton County, Arkansas, Kenneth M. Ball, Leo Carson Davis Jan 1993

Sinkhole Excavations In Peccary Cave, Newton County, Arkansas, Kenneth M. Ball, Leo Carson Davis

Journal of the Arkansas Academy of Science

No abstract provided.


Bulletin 4274 - Tree Planting On The High Rainfall Coastal Plain, Don Bennett, Richard George Jan 1993

Bulletin 4274 - Tree Planting On The High Rainfall Coastal Plain, Don Bennett, Richard George

Bulletins 4000 -

Careful planning can mean the difference between the success or failure of a tree planting program . Healthy , well-e stablished trees stand a better chance of survival, grow faster and are more resistant to insect attack. The need for time-consuming watering in summer is also eliminated.

The high rainfall coastal plain extends from Perth to Busselton and inland to the Darling Scarp. It receives about 800 to 1000 mm annual rainfall.

Site preparation is ideally started in summer. For a winter planting, decide before March where to plant, which varieties and how many trees to plant. Early planning allows …


Glacial Deposits, Vol. 21, 1992-1993, Department Of Geography-Geology Jan 1993

Glacial Deposits, Vol. 21, 1992-1993, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Collaborative Multimedia Scientific Design In Shastra, Vinod Anupam, Chandrajit L. Bajaj Jan 1993

Collaborative Multimedia Scientific Design In Shastra, Vinod Anupam, Chandrajit L. Bajaj

Department of Computer Science Technical Reports

No abstract provided.


Distributed Modeling And Rendering Of Splines Using Ganith And Splinex, Chandrajit L. Bajaj, Jindon Chen, Susan B. Evans Jan 1993

Distributed Modeling And Rendering Of Splines Using Ganith And Splinex, Chandrajit L. Bajaj, Jindon Chen, Susan B. Evans

Department of Computer Science Technical Reports

No abstract provided.


Infarct Topography And Hemiparesis Profiles With Cerebral Convexity Infarction: The Stroke Data Bank, J. P. Mohr, M. A. Foulkes, A. T. Polis, D. (Daniel) B. Hier, C. S. Kase, T. R. Price, T. K. Tatemichi, P. A. Wolf Jan 1993

Infarct Topography And Hemiparesis Profiles With Cerebral Convexity Infarction: The Stroke Data Bank, J. P. Mohr, M. A. Foulkes, A. T. Polis, D. (Daniel) B. Hier, C. S. Kase, T. R. Price, T. K. Tatemichi, P. A. Wolf

Chemistry Faculty Research & Creative Works

For the 183 of 1276 Patients in the NINDS Stroke Data Bank with Convexity Infarction in the Middle Cerebral Artery Territory, the Size of the Infarct Did Not Differ between the Two Sides But the Location of the Main Site of the Infarct Differed: on the Left Side, It Was Centered in the Inferior Parietal Region, and Was Mid-Frontal on the Right. There Was a Good Correlation between Infarct Size and Weakness Severity Whether Estimated by overall Motor Function on One Side, Arm, or Hand Alone. There Was a Poor Correlation, However, for Lesion Location (Lower Third, Middle Third or …


The Extent Of Multimedia Computer Applications In The Business World, Mei Yee Lim Jan 1993

The Extent Of Multimedia Computer Applications In The Business World, Mei Yee Lim

Honors Theses

The world, or at least I, was all agog when touch screens arrived. My initial contact with touch screens was at a science exhibition in Menara MPPJ, Petaling Jaya, Malaysia in July 1987. That particular exhibit, which encouraged visitors to participate and to experiment with, was a graphic program. Visitors could use their fingers to select the drawing tool or the color they want (which is something like the tools on a MacDraw screen on a Macintosh) and use their fingers to move around the screen to draw anything they want. That added to my fascination with the world of …


Multimedia - Hype Or No?, Robert Fuller Jan 1993

Multimedia - Hype Or No?, Robert Fuller

Robert G. Fuller Publications

Commonly, multimedia is used as a modern name for interactive video. It simply means using a computer to control the presentation of video images to an audience. It facilitates glitzy presentations of boring data. In my view, this is hype.

However, there is a more profound sense of the term. Multimedia can be seen in an historical context that places it in the tradition that began with Vannevar Bush, director of the U.S. Office of Scientific Research and Development, who in 1945 published an article, "As We May Think" in the Atlantic Monthly. In that article he suggested a "future …


Time-Stratigraphic Reconstruction And Integration Of Paleopedologic, Sedimentologic, And Biotic Events (Willwood Formation, Lower Eocene, Northwest Wyoming, U.S.A.), Thomas M. Bown, Mary J. Kraus Jan 1993

Time-Stratigraphic Reconstruction And Integration Of Paleopedologic, Sedimentologic, And Biotic Events (Willwood Formation, Lower Eocene, Northwest Wyoming, U.S.A.), Thomas M. Bown, Mary J. Kraus

United States Geological Survey: Staff Publications

Relative paleosol maturities are inversely proportional to the accumulation rates of the sediment upon which they formed, and are therefore excellent relative indicators of how much geologic time elapsed between any two horizons. An empirically-based model is advanced using paleosol maturities to estimate the relative geologic time separating any stratigraphic levels within the lower Eocene Willwood Formation. The revised Willwood time stratigraphy from this analysis helps evaluate the nature, tempo, and possible causes of three major episodes of mammalian appearance and disappearance. These faunal events are directly correlated with certain aspects of paleosol evolution in the Willwood Formation. That evolution …


Ecology Of The State Endangered Yellow Mud Turtle, Kinosternon Flavescens In Henry Co., Illinois, Michael W. Tuma Jan 1993

Ecology Of The State Endangered Yellow Mud Turtle, Kinosternon Flavescens In Henry Co., Illinois, Michael W. Tuma

Masters Theses

Illinois populations of the state endangered yellow mud turtle (Kinosternon flavescens) persist in scattered locations on sand prairies. The largest population occurs on a remnant sand prairie of the former Green River Marsh in Henry Co. A study was conducted during 1992 to determine important criteria for preserve design. These criteria included extent of turtle movements within the site and habitat use. Turtles were captured by aquatic hoop traps, drift fence, and by hand from May 11 to August 31. A total of 16 adults, four juveniles, and eight hatchlings were captured. Population size was estimated at 44.80 adults using …


A Facile Route To Allylic Phosphonates Via Base-Catalyzed Isomerization Of The Corresponding Vinyl Phosphonates : Remote Dianions In Synthesis, Synthetic Approaches To The Indolizidines, James J. Kiddle Jan 1993

A Facile Route To Allylic Phosphonates Via Base-Catalyzed Isomerization Of The Corresponding Vinyl Phosphonates : Remote Dianions In Synthesis, Synthetic Approaches To The Indolizidines, James J. Kiddle

Dissertations

No abstract provided.


Trypanosoma (Nannomonas) Congolense: Molecular Characterization Of A New Genotype From Tsavo, Kenya, P. A.O. Majiwa, M. Maina, J. N. Waitumbi, S. Mihok, E. Zweygarth Jan 1993

Trypanosoma (Nannomonas) Congolense: Molecular Characterization Of A New Genotype From Tsavo, Kenya, P. A.O. Majiwa, M. Maina, J. N. Waitumbi, S. Mihok, E. Zweygarth

All Peer-Reviewed Publications

Trypanosoma (Nannomonas) congolense comprises morphologically identical but genetically heterogeneous parasites infective to livestock and other mammalian hosts; three different genotypes of this parasite have been described previously. Restriction enzyme fragment length polymorphisms (RFLPs) in both kinetoplast DNA minicircle and nuclear DNA sequences, and randomly amplified polymorphic deoxyribonucleic acid (RAPD) patterns have been used here to demonstrate the existence of another type of T. (N.) congolense that is genotypically distinct from those that have so far been characterized at the molecular level. A highly repetitive, tandemly arranged DNA sequence and oligonucleotide primers, for use in polymerase chain reaction (PCR) amplification are …


Aminolysis Of Activated Esters Of Indole-3-Acetic Acid In Acetonitrile, Michael J. Pfeiffer, Samir B. Hanna Jan 1993

Aminolysis Of Activated Esters Of Indole-3-Acetic Acid In Acetonitrile, Michael J. Pfeiffer, Samir B. Hanna

Chemistry Faculty Research & Creative Works

Seven activated esters of indole-3-acetic acid (IAA) [4-oxo-l,2,3-benzotriazin-3-yl indole-3-acetate (IAA-3HBO), succinimido indole-3-acetate (IAA-NHS), 5-norbornene-1,3-dicarboximido indole-3-acetate (IAA-NHND), phthalimido indole-3-acetate (IAA-NHP), naphthalimido indole-3-acetate (IAA-NHN), 4-nitrophenyl indole-3-acetate (IAA-4NP), 8-quinolyl indole-3-acetate (IAA-8HQ)] were prepared and characterized. Their kinetics of aminolysis with butylamine, piperidine, and pyrrolidine in acetonitrile were investigated. In general, the observed pseudo-first-order rate constants, kobs, fit the two-term rate equation kobs = k1[amine] + k2[amine]2. For the aminolysis of six of the esters with piperidine there was no measurable k2 term. The 8-hydroxyquinoline ester and N-hydroxy-naphthalimide ester of indole-3-acetic acid had no measurable k2 term for aminolysis with either pyrrolidine or piperidine. …


A Reproductive-Resting Stage In An Harpacticoid Copepod, And The Significance Of Genetically Based Differences Among Populations, D. J. Lonsdale, P. Weissman, Fred C. Dobbs Jan 1993

A Reproductive-Resting Stage In An Harpacticoid Copepod, And The Significance Of Genetically Based Differences Among Populations, D. J. Lonsdale, P. Weissman, Fred C. Dobbs

OES Faculty Publications

Dormancy is an important life-history strategy which allows copepods to increase their fitness by delaying growth and reproduction until harsh environmental conditions have ameliorated. For marine species, the primary strategies identified to date include the production of dormant eggs by shallow-water species, and copepodite overwintering in deep-water species. Herein, we describe a third strategy in which fertilized adult females enter a “reproductive-resting” stage during the late fall that allows them to overwinter and provide a first source of spring naupliar recruitment. This strategy has been observed in the estuarine copepod Coullana canadensis, but may also occur in other species. …


Spatial And Temporal Occurrence Of Spanish Mackerel Scomberomorus Maculatus In Chesapeake Bay, Mark E. Chittenden Jr., Luiz R. Barbieri, Cynthia M. Jones Jan 1993

Spatial And Temporal Occurrence Of Spanish Mackerel Scomberomorus Maculatus In Chesapeake Bay, Mark E. Chittenden Jr., Luiz R. Barbieri, Cynthia M. Jones

OES Faculty Publications

No abstract provided.


Benthic Microalgal Production At Stellwagen Bank, Massachusetts Bay, Usa, Lawrence B. Cahoon, Guy R. Beretich Jr., Carrie J. Thomas, Amy M. Mcdonald Jan 1993

Benthic Microalgal Production At Stellwagen Bank, Massachusetts Bay, Usa, Lawrence B. Cahoon, Guy R. Beretich Jr., Carrie J. Thomas, Amy M. Mcdonald

OES Faculty Publications

Benthic microalgal chlorophyll a and production were measured at 3 sites at Stellwagen Bank, a cold temperate continental shelf habitat in Massachusetts Bay, USA, during August 1991. Benthic microalgal chlorophyll a averaged 39.8 Mg M-2, vs average integrated phytoplankton chlorophyll a of 25.9 mg m-2. Gross benthic microalgal production, measured by oxygen exchange in clear and opaque benthic chambers, averaged 20.9 mg C m-2 h-1. This production was supported by average daily light fluxes to the bottom that never exceeded 1 % of surface incident radiation and were as low as 4.7 μE …