Open Access. Powered by Scholars. Published by Universities.®

Education Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 31 - 48 of 48

Full-Text Articles in Education

Cover - Table Of Contents Jan 1994

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Use Of Ion Exchange Membranes For Selective Recovery Of Aspergillus Awamori Glucoamylase And Phage T4 Lysozyme, Deborah K. Stafslein, Jeff M. Hunter, Craig E. Forney Jan 1994

Use Of Ion Exchange Membranes For Selective Recovery Of Aspergillus Awamori Glucoamylase And Phage T4 Lysozyme, Deborah K. Stafslein, Jeff M. Hunter, Craig E. Forney

Journal of the Iowa Academy of Science: JIAS

Our research examined whether enhanced separation and purification of mutant enzymes could be obtained on ion-exchange membranes. Solutions of three mutants of Aspergillus awamori glucoamylase were passed through an anionic exchange membrane, as well as one mutant of T4 lysozyme through a cationic exchange membrane. The mutant enzymes were modified by adding "charged fusions'', polypeptides of either aspartic acid residues to increase the overall negative charge of the enzyme or arginine residues to increase the overall positive charge. The effect of the mutations on the purification of glucoamylase from a "modified" fermentation broth were examined at two different elution pHs, …


Selective Recovery Of Β-Galactosidase With Charged Fusion Tails Using Ion-Exchange Membranes, Erika A. Thiem, Meng H. Heng Jan 1994

Selective Recovery Of Β-Galactosidase With Charged Fusion Tails Using Ion-Exchange Membranes, Erika A. Thiem, Meng H. Heng

Journal of the Iowa Academy of Science: JIAS

We explored the feasibility of attaching charged tails to a target protein, in this case β-galactosidase, for selective recovery. In this process, an ion-exchange membrane was used for selective binding and release of β-galactosidase with the attached purification fusions. Strength of binding and purity of eluate increased with increasing tail length. In addition, activity yield was improved with the implementation of an intermediate partial elution recycle procedure.


Parallel Algorithms For Solving Partial Differential Equations, Stacy Pschenica Jan 1994

Parallel Algorithms For Solving Partial Differential Equations, Stacy Pschenica

Journal of the Iowa Academy of Science: JIAS

This paper describes the use of a parallel computer system in applying a finite difference method to solve various types of partial differential equations. A sequential implementation of this method was made parallel by essentially spatially decomposing the problem domain into pieces that could be separately analyzed and assigning each piece to a processor in a large, multi-processor system. Although this approach is attractive in theory, it suffers in practice because of inter-processor interactions. Thus, particular emphasis was placed on developing efficient methods for the sharing of information among the processors.

Initially, a simple two-dimensional board game, life, was implemented …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1994

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Front Matter Jan 1994

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Evaluation Of Implanted Radio Transmitters In Pheasant Chicks, Dean E. Ewing, William R. Clark, Paul A. Vohls Jan 1994

Evaluation Of Implanted Radio Transmitters In Pheasant Chicks, Dean E. Ewing, William R. Clark, Paul A. Vohls

Journal of the Iowa Academy of Science: JIAS

We studied game-farm pheasant (Phasianus colchicus Linneaus) chicks implanted with miniature transmitters to determine if surgery and implantation affected growth, behavior, or survival. Transmitters (weighing 1.2 g) were implanted subcutaneously in the interscapular region in day-old chicks. In Experiment 1, biological effects on chicks with transmitters implanted were compared with data from a control group. In Experiment 2, the effects of anesthesia only, anesthesia with an implanted transmitter, and implanted transmitter only were compared with a control. We measured responses of weight gain, survival, and pecking behavior in each experiment. In Experiment 1, we found no significant differences in weight …


Back Cover Jan 1994

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Front Matter Jan 1994

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Ecoregions And Subregions Of Iowa: A Framework For Water Quality Assessment And Management, Glenn E. Griffith, James M. Omernik, Thomas F. Wilton, Suzanne M. Pierson Jan 1994

Ecoregions And Subregions Of Iowa: A Framework For Water Quality Assessment And Management, Glenn E. Griffith, James M. Omernik, Thomas F. Wilton, Suzanne M. Pierson

Journal of the Iowa Academy of Science: JIAS

Ecoregion frameworks are valuable tools for inventorying and assessing environmental resources, for setting resource management goals, and for developing biological criteria and water quality standards. In a collaborative project between the Iowa Department of Natural Resources (DNR) and the U.S. Environmental Protection Agency (EPA), we have refined boundaries of the EPA's five ecological regions of Iowa and defined six subregions of the Western Corn Belt Plains ecoregion within the state. Lists of candidate stream reference sites have been developed to date for the seven largest regions, and the sites were visited and evaluated by Iowa DNR and U.S. EPA personnel …


Analysis Of An Iowa Aridity Index In Relationship To Climate And Crop Yield, Soumare Harouna, R. E. Carlson Jan 1994

Analysis Of An Iowa Aridity Index In Relationship To Climate And Crop Yield, Soumare Harouna, R. E. Carlson

Journal of the Iowa Academy of Science: JIAS

An aridity index and its components, temperature and precipitation, for the period from 1900 through April 1993 were defined and characterized. This index describes the anomalous behavior of both temperature and precipitation over time. Our intent was to examine climate variability in Iowa. Moving mean and standard deviations over various lengths of time were calculated from three time series. We found that these indices fluctuate considerably from year to year and from month to month. The lowest aridity index values occurred in the recent summer of 1992, and the highest occurred during the very drought-prone 1930s. The 12-month moving mean …


Relation Between S2 And Later Generation Testcrosses Of Two Corn Populations, S. M. Lile, A. R. Hallauer Jan 1994

Relation Between S2 And Later Generation Testcrosses Of Two Corn Populations, S. M. Lile, A. R. Hallauer

Journal of the Iowa Academy of Science: JIAS

Determination of the relative combining abilities of corn (Zea mays L.) inbred lines is an important feature of applied corn breeding programs. Combining ability is measured by the relative performance of a line in testcrosses to one or more testers. Inbred lines from BS13(S2)Cl and BSCB1(R)C7 corn populations were evaluated at the S2 and later generations of inbreeding. Intense selection was practiced among and within lines during inbreeding to develop the S5-equivalent and S8 generation lines. The objective of this study was to determine if the combining ability of lines in early generations (S2) …


Editorial Board & Iowa Academy Of Science Officers And Directors Jan 1994

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Nuclear Waste Into Glass: Viscosities Of Molten Analogs Of Radioactive Waste Disposal Media, Betty Pang, Kenneth E. Windom Jan 1994

Nuclear Waste Into Glass: Viscosities Of Molten Analogs Of Radioactive Waste Disposal Media, Betty Pang, Kenneth E. Windom

Journal of the Iowa Academy of Science: JIAS

Disposal of high-level radioactive wastes involves vitrification of a mixture of waste products and borosilicate glass frit. Monitoring the composition of the mixture is critical to the control of the vitrification process, bur is difficult because of the high levels or radioactive components in the mixture. Synthetic non-radioactive analogs of the products from nuclear reprocessing have been prepared and their viscosities measured over a wide range of temperature appropriate to those of the vitrification process. Preliminary results indicate that viscosity is a linear function of composition, under isothermal conditions, for a limited compositional range that encompasses the proportions of waste …


Back Cover Jan 1994

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Note To Members And Subscribers, Paul E. Rider Jan 1994

Note To Members And Subscribers, Paul E. Rider

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Water Quality Monitoring (1988 To 1991) At The Iowa Academy Of Science's Parish Farm, Grundy County, Iowa, Brenda K. Nations, George R. Hallberg Jan 1994

Water Quality Monitoring (1988 To 1991) At The Iowa Academy Of Science's Parish Farm, Grundy County, Iowa, Brenda K. Nations, George R. Hallberg

Journal of the Iowa Academy of Science: JIAS

In May 1988 sampling was initiated to evaluate water quality in relation to management practices at Parish Farm, which is owned by Iowa Academy of Science. Initial results showed tile-line effluent to have high concentrations of nitrate-nitrogen (N03-N). Twelve monitoring wells were installed over a one year period to analyze shallow groundwater at the farm. The wells, tile lines, and surface water were sampled monthly, through October, 1991, and the water analyzed for N03-N and some pesticides. N03-N concentrations varied, related to landuse and management of adjacent areas. Greater N03-N concentrations were …


Nomenclatural Changes For Some Diatoms Found In Iowa, David B. Czarnecki Jan 1994

Nomenclatural Changes For Some Diatoms Found In Iowa, David B. Czarnecki

Journal of the Iowa Academy of Science: JIAS

Nomenclatural revisions for four diatom taxa found in Iowa, two of which are presently maintained in the Loras College Freshwater Diatom Culture Collection (FDCC), are necessary because of systematic interpretations of the Division Bacillariophyta. Achnanthidium hauckianum (Grun.) Czarnecki comb. nov. was originally assigned to the genus Achnanthes Bory. Three taxa were previously assigned to the morphologically diverse genus Navicula Bory. These are Cavinula weinzierlii (Schimanski) Czarnecki comb. nov., Craticula cuspidata var. major [(Meist.) Czarnecki comb. nov. and] Craticula halophila var. subcapitata (0str.) Czarnecki comb. nov.