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An Interpretation Of Hustedt's Terms "Schattenlinie", "Perlenreihe" And "Hocker" Using Specimens Of The Cyclotella Radiosa-Complex, C. Distinguenda, Hust., And C. Cyclopuncta Nov. Sp., Hannelore Hakansson, John R. Carter Jan 1990

An Interpretation Of Hustedt's Terms "Schattenlinie", "Perlenreihe" And "Hocker" Using Specimens Of The Cyclotella Radiosa-Complex, C. Distinguenda, Hust., And C. Cyclopuncta Nov. Sp., Hannelore Hakansson, John R. Carter

Journal of the Iowa Academy of Science: JIAS

With the help of light- and scanning electron micrographs HUSTEDT'S terms "Schattenlinie", "Perlenrcihe", and "Hocker" are explained using specimens in the Cydotella radiosa complex, and C. distinguenda HUST. The complicated history of C. operculata (AG.) KUTZ., published elsewhere, has shown that C. distinguenda HUST. is the correct name to be used for this taxon. In this connection the new nomenclatural combination C. distinguenda var. unipunctata nov. comb. is proposed.

Morphological differences are discussed and the possibility of different "unipunctata" species is shown. Distinct morphological features found indicate the necessiry to describe a new species: C. cyclopuncta nov. sp. rather than …


The Mating Systems And Pollination Biology Of Three Species Of Verbena (Verbenaceae), Robert W. Cruden, Kristina K. Baker, Thomas E. Cullinan, Karen A. Disbrow, Kelly L. Douglas, John D. Erb, Kenneth J. Kirsten, Mary L. Malik, Elizabeth A. Turner, Jonathon A. Weier, Sherry R. Wilmot Jan 1990

The Mating Systems And Pollination Biology Of Three Species Of Verbena (Verbenaceae), Robert W. Cruden, Kristina K. Baker, Thomas E. Cullinan, Karen A. Disbrow, Kelly L. Douglas, John D. Erb, Kenneth J. Kirsten, Mary L. Malik, Elizabeth A. Turner, Jonathon A. Weier, Sherry R. Wilmot

Journal of the Iowa Academy of Science: JIAS

Because their flowers can be cross- and/or self-pollinated Verbena stricta, V hastata and V urticifolia are facultatively xenogamous. We suggest the flowers can be cross-pollinated because I) the fruit set of caged plants was substantially lower than that of open-pollinated plants, i.e. pollinators were necessary for typical fruit set and 2) the flowers of each species attracted a diverse array of hymenopteran, dipteran and lepidopteran pollinators that were capable of moving pollen between plants. Self-pollination was low due to the spatial separation of anthers and stigmas and/or an angled corolla that decreased the likelihood of pollen dropping from the anthers …


A Summer Course In Invertebrate Developmental Biology At Iowa Lakeside Laboratory: A Unique Experience, Carol W. Schutte, Dale J. Witt, Nicole Y. Janosek, Douglas E. Robinson, Edwin C. Powell, George G. Brown Jan 1990

A Summer Course In Invertebrate Developmental Biology At Iowa Lakeside Laboratory: A Unique Experience, Carol W. Schutte, Dale J. Witt, Nicole Y. Janosek, Douglas E. Robinson, Edwin C. Powell, George G. Brown

Journal of the Iowa Academy of Science: JIAS

The course, "Developmental Biology of Selected Invertebrates'', has been offered in alternate years at Iowa Lakeside Laboratory (Ill) on Lake West Okoboji, Dickinson County, Iowa, since the first summer session of 1983. This course has taken advantage of the great diversity of invertebrates found in the Ill area and has demonstrated to students and faculty alike the exciting phenomena and principles of developmental biology. The course is continuously evolving as new experiments and observations are discovered with each offering of the course.


Changes In A Prairie Bird Population From 1940 To 1989, Neil P. Bernstein, Kristine K. Baker, Sherry R. Wilmot Jan 1990

Changes In A Prairie Bird Population From 1940 To 1989, Neil P. Bernstein, Kristine K. Baker, Sherry R. Wilmot

Journal of the Iowa Academy of Science: JIAS

We repeated a bird census of a prairie/field community that was done by Kendeigh (1941) in 1940. Changes in the bird populations were compared with changes in vegetation, agricultural land use for the county, and trends in urbanization. Grassland birds did decline in abundance due to causes similar to those cited in other studies. The increase in forest and edge nesting species was more unusual to this study, and probably correlated with the woody succession that had occurred.


Improving The Analytical Recovery Of Radiostrontium From Environmental Samples, Luz Selenia Acosta Jan 1990

Improving The Analytical Recovery Of Radiostrontium From Environmental Samples, Luz Selenia Acosta

Retrospective Theses and Dissertations

No abstract provided.


Back Cover Jan 1990

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Glacial Deposits, Vol. 18, 1989-1990, Department Of Geography-Geology Jan 1990

Glacial Deposits, Vol. 18, 1989-1990, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Lapita Fishing Strategies: A Review Of The Archaeological And Linguistic Evidence, Richard Walter Nov 1989

Lapita Fishing Strategies: A Review Of The Archaeological And Linguistic Evidence, Richard Walter

Pacific Studies

No abstract provided.


Student Fact Book, Fall 1989, Wright State University 25 Years Vision Unlimited, Office Of Student Information Systems, Wright State University Oct 1989

Student Fact Book, Fall 1989, Wright State University 25 Years Vision Unlimited, 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, 1989.


Feasibility Of An Extraoral Method For Predicting Manibular Incisor Relapse, Mark J. Saylor Jun 1989

Feasibility Of An Extraoral Method For Predicting Manibular Incisor Relapse, Mark J. Saylor

Loma Linda University Electronic Theses, Dissertations & Projects

The author undertook to develop an extraoral model for predicting mandibular incisor relapse similar to the model described by Harvey and Sheldon Peck. Whereas the Peck and Peck method involves intraoral measurements, the method described in this paper relied on the taking of measurements from the patient's pre-treatment plaster models. Two hundred and sixty teeth were measured both orally and on plaster casts, and several statistical tests were performed to isolate any differences between the intraoral and extraoral methods. The principal difference was identified as the faciolingual measurement of the incisor, due to the height of contour often being subgingival …


Jim Bindon's Review Of Tsuguyoshi Suzuki And Ryutaro Ohtsuka's Human Ecology Of Health And Survival In Asia And The South Pacific, Jim Bindon Mar 1989

Jim Bindon's Review Of Tsuguyoshi Suzuki And Ryutaro Ohtsuka's Human Ecology Of Health And Survival In Asia And The South Pacific, Jim Bindon

Pacific Studies

No abstract provided.


Kansas Attitudes On Prairie Dog Control, Charles D. Lees, F. Robert Henderson Feb 1989

Kansas Attitudes On Prairie Dog Control, Charles D. Lees, F. Robert Henderson

Great Plains Wildlife Damage Control Workshop Proceedings

In Kansas prairie dog management is primarily determined by private individuals and local government agencies. We conducted a mail survey of 350 affected landowners as a means to evaluate the effectiveness of current prairie dog control. The same survey was also sent to 350 randomly selected state residents within the general prairie dog range. We evaluated people's perceptions of prairie dogs, the effectiveness of control methods, costs of control, and reasons for poor response to control techniques. Results indicate people that have previously been involved in prairie dog control on lands they manage have different opinions about prairie dogs than …


Natural And Anthropogenic Forces Acting On A Forest Lake, M. C. Whiteside, M. B. King, K. Pulling Jan 1989

Natural And Anthropogenic Forces Acting On A Forest Lake, M. C. Whiteside, M. B. King, K. Pulling

Journal of the Minnesota Academy of Science

ABS1RACT-Lak~ Itasca, Minnes~ta is located within one of the more popular state parks. Since the turn of the centmy, loggmg, fire protection, and development within the watershed have put modest pressures on the ecosystem. The presence of the University of Minnesota's Biological and Forestry Station on the lake has encouraged research in this region. Consequently there are numerous research reports and papers which are available _at the station's library. We examined data collected over the past 25 years to see if we could detect changes ~~ the lake. We detected no changes in phytoplankton, macrophyte, zooplankton, or zoobenthos com~urnues, but …


Geology Of The Pre-Dune Strata, James B. Swinehart, Robert F. Diffendal Jr. Jan 1989

Geology Of The Pre-Dune Strata, James B. Swinehart, Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

Over the last 98 million years, four general geological processes have acted to shape the ancient landscapes buried beneath the Sand Hills. Three of these affected the area directly, either depositing sediments on the land surface or eroding it, while a fourth took place west of Nebraska, but affected the region nonetheless.

Shells of clams, oysters, and numerous other kinds of creatures similar to forms that live today in the seas are preserved as fossils in the chalks, limestones, and shales that form the oldest rocks beneath the Sand Hills that will be described. These deposits indicate to geologists that …


Plant-Parasitic Nematodes In Iowa, Don C. Norton Jan 1989

Plant-Parasitic Nematodes In Iowa, Don C. Norton

Journal of the Iowa Academy of Science: JIAS

Ninety-nine species of plant-parasitic nematodes are recorded from Iowa. Twenty-seven are new state records. Most samples were collected from around maize or from prairies or woodlands. Similarity (Sorensen's index) of species was highest for the maize-prairie habitats (0.49), compared with maize-woodlands (0. 23), or prairie-woodland (0. 3 7) habitats. Nematode communities were most diverse in prairies with a Shannon-Weiner index (H') of 2.74, compared with 1.65 and 1.07 for woodlands and maize habitats, respectively. Evenness of species (J') was 0.41, 0.78, and 0.48 for maize, prairies, and woodlands, respectively.


Front Matter Jan 1989

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Program Abstracts, 101st Session, Iowa Academy Of Science, April 21-22, 1989, Buena Vista College Jan 1989

Program Abstracts, 101st Session, Iowa Academy Of Science, April 21-22, 1989, Buena Vista College

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Annual Report Of The Iowa Academy Of Science, 1988-89, Paul E. Rider Jan 1989

Annual Report Of The Iowa Academy Of Science, 1988-89, 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, 1988 to June 30, 1989. 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, who is writing his first annual report.


Back Cover Jan 1989

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Socioeconomic Aspects Of Small-Scale Commercial Fisheries Development In The Republic Of The Marshall Islands, Cheryl Ann Mandich Jan 1989

Socioeconomic Aspects Of Small-Scale Commercial Fisheries Development In The Republic Of The Marshall Islands, Cheryl Ann Mandich

Marine Affairs Theses and Major Papers

This study examines the sociocultural aspects of fishery development in the Republic of the Marshall Islands. It is based upon field research conducted through interviews with indigenous fisherfolk, business people, and expatriates. The Marshall Islands were selected because they have a limited economic base, yet have abundant fishery resources which have considerable potential to generate foreign exchange. Many studies focus on the technical aspects of fishery resource development. However, none address the sociocultural factors that influence its success. This thesis demonstrates that several aspects of Marshallese fishing society, some of which correspond to characteristics of the peasantry identified by Rogers …


Estimates Of Genetic Variability In F2 Maize Populations, Geng-Chen Han, A. R. Hallauer Jan 1989

Estimates Of Genetic Variability In F2 Maize Populations, Geng-Chen Han, A. R. Hallauer

Journal of the Iowa Academy of Science: JIAS

Maize (Zea mays L.) breeders emphasize selection within F2 populations derived from crosses of inbred lines: Studies of the inheritance of quantitative traits in maize have been conducted primarily for generically broad-based populations. Objectives of our study were to estimate the generic variability in F2 populations developed from crosses of related and unrelated lines and to determine the effects of five generations of random intermating of plants within F2 populations on the estimates of genetic variability. Estimates of additive genetic variability were greater in the unrelated line crosses, but the estimates were not significantly different before and …


Back Cover Jan 1989

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Back Cover Jan 1989

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Semiquantitative Measurement Of Fission Produced Gamma Ray Radioactivity In Soils At Dubuque, Iowa, James A. Dockal, James A. Dockal Sr. Jan 1989

Semiquantitative Measurement Of Fission Produced Gamma Ray Radioactivity In Soils At Dubuque, Iowa, James A. Dockal, James A. Dockal Sr.

Journal of the Iowa Academy of Science: JIAS

Residual fission-product radionuclide contamination (fallout) in soils at Dubuque, Iowa was evaluated with an Exploration geometrics gamma ray scintillometer in 1985 and after the Chernobyl accident in 1986. Anomalous amounts of gamma ray radiation were found near where downspouts discharged storm runoff from the roof of a dwelling. The 1985 residual cesium-13 7 activity in the soils of the area was found to be 0.2 pCi/gram with an areal contamination of 16 ± nCi/m2. Activities associated with the soils near the discharge points of the downspouts ranged as high as 8 pCi/gram. This contamination seems to have occurred prior to …


Cytoplasmic Effect On Groat Protein Content In Lnterspecific Matings Of Avena Sativa L. And A. Sterilis L., A. Rezai, K. J. Frey Jan 1989

Cytoplasmic Effect On Groat Protein Content In Lnterspecific Matings Of Avena Sativa L. And A. Sterilis L., A. Rezai, K. J. Frey

Journal of the Iowa Academy of Science: JIAS

Thirty sets of reciprocal isopopulations, each with 20 Fi-derived oat lines from the BC0, BC1, and BC2 of all possible matings among five Awia slerilis L. accessions and two A. saliva cultivars, were evaluated in a replicated field trial to determine whether groat protein content was influenced by cytoplasmic inheritance and to study associations between protein content and agronomic traits. A. slerili cytoplasm had no direct effect on groat protein content, but significant interactions between the cytoplasms and nuclear genes from A. saliva and A. s1erilis were detected. Thus, the potential may exist for improving …


Ua56/1 Fact Book, Wku Institutional Research Jan 1989

Ua56/1 Fact Book, Wku Institutional Research

WKU Administration Documents

Statistical and demographic profile of WKU.


Front Matter Jan 1989

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Additions To The Iowa Pteridophyte Flora - Iii, James H. Peck Jan 1989

Additions To The Iowa Pteridophyte Flora - Iii, James H. Peck

Journal of the Iowa Academy of Science: JIAS

To prior reports on the studies of the Iowa pteridophyre flora, five taxa (Botrychium campestre Wagner & Farrar, Botrychimn matricariifolium A. Braun, CyJtopterislragilis (L) Bernh., Cystopteris laurentiana (Weath.) Blasdell, and Lycopodium inundatum L.) are added, along with 215 new county occurrence records for 39 taxa. Currently, the Iowa preridophyte flora consists of 70 taxa, supported with 1656 county occurrence records; only 72 (4%) of these records are based solely on collections made before 1950.


Biological Pesticides: Biotechnology's Answer To Silent Spring, Donald H. Dean Jan 1989

Biological Pesticides: Biotechnology's Answer To Silent Spring, Donald H. Dean

Journal of the Iowa Academy of Science: JIAS

In the 25 years since the publication of Rachel Carson’s Silent Spring the public has come to realize the environmental impact of heavy use of chemical pesticides. To add insult to injury, many insects, including the disease vector, the mosquito, are now virtually resistant to standard chemical pesticides. Biotechnology is now providing a positive response to these dilemmas through the production and development of improved forms of microbial pest control agents: biological pesticides. Biological pesticides are pathogens, or predators, of insects such as bacteria, fungi, and viruses, and predatory insects or vertebrates such as mosquito fish which reduce the population …


Questions And Discussion [The Scientist's Role In The Controversy Over Genetic Engineering, Regulation And Utilization Of Microorganisms: A Symposium], Arthur Weissinger Jan 1989

Questions And Discussion [The Scientist's Role In The Controversy Over Genetic Engineering, Regulation And Utilization Of Microorganisms: A Symposium], Arthur Weissinger

Journal of the Iowa Academy of Science: JIAS

No abstract provided.