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Cover - Table Of Contents
Journal of the Iowa Academy of Science: JIAS
No abstract provided.
Mutant Weeds Of Iowa: V. S-Triazine Resistant Setaria Faberi Herrm, R. Thornhill, J. Dekker
Mutant Weeds Of Iowa: V. S-Triazine Resistant Setaria Faberi Herrm, R. Thornhill, J. Dekker
Journal of the Iowa Academy of Science: JIAS
S-triazine resistance in giant foxtail (Setaria faberi Herrm.) has been reported previously, but not in the midwestern U.S. corn belt or Iowa. A study was conducted using a chlorophyll fluorescence assay to confirm the presence of resistance in one S. faberi population in Iowa. Variable chlorophyll fluorescence assays confirmed that a population of this species with this type of resistance exists in Iowa. This is the first report of s-triazine resistance in S. faberi, and the fourth species with this type of herbicide resistance, found in an Iowa agroecosystem.
A Gravity Investigation Of The Fayette Structural Zone And Surrounding Area, Northeast Iowa, Richard L. Kellogg, Christopher Meinen
A Gravity Investigation Of The Fayette Structural Zone And Surrounding Area, Northeast Iowa, Richard L. Kellogg, Christopher Meinen
Journal of the Iowa Academy of Science: JIAS
A gravity survey was conducted over approximately 2600 square kilometers of northeast Iowa. The survey was undertaken to provide detailed gravity coverage at approximately one mile intervals and to investigate the sources of gravity anomalies in the study area. An additional objective was to verify with gravity data the presence of the Fayette Structural Zone, previously identified on the basis of magnetic linears. Four hundred and twenty-seven gravity stations were occupied and data from these stations combined with extant data from the Geological Survey Bureau of the Iowa Department of Natural Resources to produce the gravity interpretation. A Bouger gravity …
Index For Volume 100
Journal of the Iowa Academy of Science: JIAS
No abstract provided.
Advances In Biomolecule Analysis: Ftms Of Macromolecules, Curtiss D. Hanson, Ira M. Simet, Suzanne R. Smith
Advances In Biomolecule Analysis: Ftms Of Macromolecules, Curtiss D. Hanson, Ira M. Simet, Suzanne R. Smith
Journal of the Iowa Academy of Science: JIAS
The development of Fourier transform ion cyclotron resonance (FT-ICR) as an analytical technique has opened new avenues to the analysis of high molecular weight biomolecules. Because mass analysis is based on a detection of a frequency, it is possible to obtain high resolution mass measurements without sacrificing sensitivity. The unique ability to analyze high mass ions is based in the design of a passive ExB ion trap. Although in the past, field inhomogeneities have limited this technique, recent developments in both trap designs and excitation techniques have resulted in major improvements in both sensitivity and resolution.
Cover - Table Of Contents
Journal of the Iowa Academy of Science: JIAS
No abstract provided.
Floristic Composition And Conservation Status Of Fens In Iowa, John A. Pearson, Mark J. Leoschke
Floristic Composition And Conservation Status Of Fens In Iowa, John A. Pearson, Mark J. Leoschke
Journal of the Iowa Academy of Science: JIAS
Over 200 extant fens of varying condition were documented during an extensive inventory conducted in Iowa between 1986 and 1991. Approximately half of the extant fens support endangered, threatened, special concern, or other rare plant species. Approximately 25 fens are outstanding conservation prospects with intact vegetation, high species richness, and rare species. Nearly 40% of all potential fen sites have been destroyed by cultivation or damage; another 30% remain unknown due to lack of a field visit, but most appear on aerial photographs to be very small, disturbed fragments. In addition to their traditionally recognized range in northwest Iowa, fens …
In Memoriam: Harold W. Beams (1903-1992), Richard G. Kessel
In Memoriam: Harold W. Beams (1903-1992), Richard G. Kessel
Journal of the Iowa Academy of Science: JIAS
Harold W. Beams, long time Professor of Biology at the University of Iowa, died at his home in Iowa City on January 26, 1992 after an illness of several months. Professor Bearns was born in Belle Plaine, Kansas on August 3, 1903. He received the B.A. Degree in 1925 from Wichita State University, the M.A. Degree in Zoology in 1926 from Northwestern University, and the Ph. D. Degree in Zoology in 1928 from the University of Wisconsin.
The Distribution Of Amphipods In Southeastern Minnesota And Their Relation To Water Quality And Land Use, James A. Muck, Raymond M. Newman
The Distribution Of Amphipods In Southeastern Minnesota And Their Relation To Water Quality And Land Use, James A. Muck, Raymond M. Newman
Journal of the Iowa Academy of Science: JIAS
The distribution of the amphipods Gammarus pseudolimnaeus and Hyalella azteca was determined from 97 designated trout streams in Minnesota, along with temperature, conductivity, and nitrate levels. Streams were classified into 4 land use/geology groups. G. pseudolimnaeus was found in 11 counties and at 123 of 168 sites in 83 of the 97 streams sampled. Hyalella azteca was found in 7 counties at 26 sites m 21 streams. Spearman rank correlations showed a high degree of correlation between nitrate (range: 0-11 mg N/L), conductivity (range: 325-870 μS/cm), and geology. The relative abundance of G. pseudolimnaeus was negatively correlated with nitrate, geology …
Geology Of Iowa Fens, C. A. Thompson, E. A. Bettis Iii, R. G. Baker
Geology Of Iowa Fens, C. A. Thompson, E. A. Bettis Iii, R. G. Baker
Journal of the Iowa Academy of Science: JIAS
Fens are peatlands which are dependent on groundwater discharge to provide nutrient enrichment. Fens are found in a variety of landscape positions and in most Iowa landform regions. This paper presents a classification system for Iowa fens based on landscape position, stratigraphy, and hydrologic factors. Iowa fens can be separated into six categories: 1) fens along valley wall slopes; the groundwater source for these fens is sand and gravel buried between glacial tills (inter-till); 2) fens in hummocky topography on the northwestern margin of the Des Moines Lobe landform region; the water source is sand and gravel buried within glacial …
The University Of Iowa Museum Of Natural History: An Historical Perspective, George D. Shrimper
The University Of Iowa Museum Of Natural History: An Historical Perspective, George D. Shrimper
Journal of the Iowa Academy of Science: JIAS
The 132-year record of UIMNH essentially mirrors historical and on-going trends in related institutions. As scholarship grew in the natural sciences during the 19th century, natural history museums became centers for scientific research. A "Golden Age" of museum-based expeditionary work and taxonomic research was marked at UI by the careers of curator/naturalists Calvin, Nutting, Macbride, and Shimek. Systematic biology and paleontology thrived with the accumulation of extensive collections. De-emphasis of "natural history" studies followed after 1920-30 with a concomitant growth in cellular and molecular biology. In seeking new directions and financial support, many museums, including UIMNH, shifted emphasis to public …
Checklist Of The Vascular Flora Of Page County, Iowa, Barbara L. Wilson
Checklist Of The Vascular Flora Of Page County, Iowa, Barbara L. Wilson
Journal of the Iowa Academy of Science: JIAS
The vascular flora of Page County, Iowa, was studied from 1987 through 1991. Seven hundred forty two species and four hybrids of vascular plants were found. A quarter of the flora consists of non-native species. Taxa not previously reported in Iowa include: Amsinckia intermedia, Brassica kaber, Cardaria chalapensis, Callirhoe bushii, Carex mesochorea, Eleocharis xyridiformis, Euphorbia prostrata, Lactuca saligna, Leontodon autumnalis, Scirpus mucronatus, Sclerochloa dura, and Vernonia arkansana.
Cover - Table Of Contents
Journal of the Iowa Academy of Science: JIAS
No abstract provided.
Necklace Radio Transmitter Attachment For Pheasants, Terry Z. Riley, Bruce A. Fistler
Necklace Radio Transmitter Attachment For Pheasants, Terry Z. Riley, Bruce A. Fistler
Journal of the Iowa Academy of Science: JIAS
We tested a pre-assembled, necklace-radio-transmitter-attachment design on female ring-necked pheasants (Phasianus colchicus) in northern Iowa. Birds were captured by nightlighting and bait trapping between September 1989 and March 1990. Radio transmitters were attached to 128 using a wire necklace. Two birds had problems adapting to the necklace, and 3 birds removed them. Twenty-three birds were still alive and wearing necklaces at the end of the study, for an average of 318 (SD= ± 52) days. Ease of attachment, long durability, light weight, and minimal bulk make the necklace an effective alternative to harness and poncho mounts.
Book Review: Landforms Of Iowa, Michael L. Thompson
Book Review: Landforms Of Iowa, Michael L. Thompson
Journal of the Iowa Academy of Science: JIAS
Many of us are interested in the landscape around us. We ask: Why is this hill so steep or why is that valley so wide? Why does my garden's soil have so much clay? Why does Iowa have no mountains' Landforms of Iowa should capture a broad audience of teachers, students, agriculturalists of all sorts, historians, homemakers, naturalists, botanists, biologists, foresters, geographers, civil engineers, as well as geologists and pedologists-in short, just about any Iowan who has ever wondered how and when the landscape at his or her doorstep or outside the car window was fashioned. Its stated purposes are …
Fifty Years Of Fisheries Management M An Obstinate Prairie Lake, Dennis L. Scarnecchia, James R. Wahl
Fifty Years Of Fisheries Management M An Obstinate Prairie Lake, Dennis L. Scarnecchia, James R. Wahl
Journal of the Iowa Academy of Science: JIAS
Little Wall Lake, a shallow 104 ha glacial lake in Hamilton County, Iowa, has been manipulated for about 50 years by fishery managers in an attempt to provide a stable sport fishery. Managers have used dredging, water level manipulation, aquatic vegetation control, mechanical fish removal and fish eradication with toxicants, sport fish stocking, introduction of piscivorous fish, artificial habitat structures, and winter aeration. Attempts to stabilize the fishery have been unsuccessful, and because of overpopulation and stunting of panfishes, total fish eradications were conducted in 1977 and 1989. We review the history of management efforts on the lake, and suggest …
Editorial Board & Iowa Academy Of Science Officers And Directors
Editorial Board & Iowa Academy Of Science Officers And Directors
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.
History Of Iowa Natural History - A Symposium, Neil P. Bernstein
History Of Iowa Natural History - A Symposium, Neil P. Bernstein
Journal of the Iowa Academy of Science: JIAS
This issue of the Journal of the Iowa Academy of Science presents the first written installment of our symposium: papers on the contributions of Keyes, Pammel, Bessey, and Hayden; the role of the Iowa Natural History Museum; and histories of both the development of early natural history studies and mammalogy investigations. More papers will follow in future issues, and new contributors are welcome.
Three Botanists: Bessey, Pammel, And Hayden, Duane Isely, Lois Tiffany
Three Botanists: Bessey, Pammel, And Hayden, Duane Isely, Lois Tiffany
Journal of the Iowa Academy of Science: JIAS
Bessey was a multidirectioned innovator and evangelist of botanical education, conservation, and scientific agriculture. For example, he initiated the first undergraduate laboratory using microscopes for botany instruciton and he had no peer as a botany teacher in the latter part of the 19th century. His enthusiasm about the natural history of Iowa and surrounding states broadened the horizons of innumerable students and he was one of the founders of the Iowa Academy of Science. An organization man, Bessey quickly became president of any group with which he became affiliated, and eventually was both nationally and internationally known through his text …
Mass Dependent Loss Of Resolution In Radially Inhomogeneous Exb Ion Traps, Mark A. Capron, Susan S. Haskin, Curtiss D. Hanson
Mass Dependent Loss Of Resolution In Radially Inhomogeneous Exb Ion Traps, Mark A. Capron, Susan S. Haskin, Curtiss D. Hanson
Journal of the Iowa Academy of Science: JIAS
ExB ion traps, such as Fourier transform Ion Cyclotron Resonance mass spectrometers (FY:ICR), mass analyze sample ions based on differences in their cyclotron frequencies in a homogeneous magnetic field. The high resolution mass measurements of FT-ICR are based on the relationship between the frequency of the cyclotron orbit and the mass-to-charge (m/q) ratio of an ion. Both the orbit and the frequency/mass relationship result from the radial forces on the ion. Ions trapped by inhomogeneous electric fields experience different magnitudes of the radial electric fields at different positions resulting in a positionally dependent frequency. Such differences in orbital frequencies for …
Cover - Table Of Contents
Journal of the Iowa Academy of Science: JIAS
No abstract provided.