Physical Sciences and Mathematics Commons^™

Selenium Accumulation In The Cockle Anadara Trapezia, Dianne F. Jolley, William A. Maher, Jennelle Kyd

Faculty of Science - Papers (Archive)

An extensive study on Se accumulation in a population of Anadara trapezia from a marine lake is reported. The effects of organism mass, gender, reproductive cycle, and season on Se accumulation and tissue distribution were investigated. Analyses showed that gender and reproductive cycle had no significant effect on Se accumulation. A. trapezia showed a strong positive correlation between Se burden and tissue mass. Constant Se concentrations were observed within individual populations but varied spatially with sediment Se concentrations. Se concentrations in tissues decreased from gills>gonad/intestineOmantleO muscleOfoot, which remained constant over 12 months, however, significantly lower concentrations were observed in …

Photosynthesis In Silico. Overcoming The Challenges Of Photosynthesis Education Using A Multimedia Cd-Rom, A. W. Russell, G. M.A. Netherwood, Sharon A. Robinson

Faculty of Science - Papers (Archive)

Photosynthesis is a central topic in biology education. It remains one of the most challenging, largely because of a) its conceptual difficulty, leading to lack of interest and misconceptions among students; b) the difficulties students have in visualising the process, or relating it to things they can see, especially when the topic is presented purely as a molecular process; and c) limitations to the practical demonstration of photosynthesis because equipment is either cheap, unreliable and antiquated or prohibitively expensive. In response, we have combined expertise in photosynthesis research and education, and in graphic design, to produce an interactive, multimedia package, …

Asymmetric Synthesis Of (+)-1-Epiaustraline And Attempted Synthesis Of Australine, Minyan Tang, Stephen G. Pyne

Faculty of Science - Papers (Archive)

A diastereoselective synthesis of the pyrrolizidine alkaloid, (+)-1-epiaustraline has been achieved via a diastereoselective syn-dihydroxylation of a pyrrolo[1,2-c]oxazol-3-one precursor that was readily prepared by a RCM reaction. Attempts to extend this methodology to the synthesis of australine were not successful since the final pyrrolidine ring closure to produce the desired pyrrolizidine of the target molecule was not productive.

Phytochemical Studies On Stemona Burkillii Prain: Two New Dihydrostemofoline Alkaloids, Pitchaya Mungkornasawakul, Stephen G. Pyne, Araya Jatisatienr, Wilford Lie, Alison T. Ung, Kritchaya Issakul, Auntika Sawatwanich, Damrat Supyen, Chaiwat Jatisatienr

Faculty of Science - Papers (Archive)

Two new dihydrostemofoline alkaloids, 11(S),12(R)-dihydrostemofoline (3) and stemoburkilline (4), along with stemofoline (1) and 2’-hydroxystemofoline (2) have been isolated from a root extract of Stemona burkillii Prain. The structure and relative configuration of (3) have been determined via spectroscopic data and from comparison with synthetic 11(S),12(S)-dihydrostemofoline (5). The configuration of the exo-cyclic alkene group in (4) is tentively assigned as (E) based upon mechanistic considerations.

Asymmetric Synthesis Of (-)-Swainsonine, Karl Lindsay, Stephen G. Pyne

Faculty of Science - Papers (Archive)

This paper describes a new synthesis of (-)-swainsonine via the ring-closing metathesis reaction of a substituted 3-allyl-4-vinyl-2-oxazolindinone and subsequent diastereoselective syn-dihydroxylation of the resulting pyrrolo[1,2-c]oxazol-3-one.

Phytochemical And Larvicidal Studies On Stemona Curtisii: Structure Of A New Pyriodo[1,2-A]Azepine Stemona Alkaloid, Pitchaya Mungkornasawakul, Stephen G. Pyne, Araya Jatisatienr, Damrat Supyen, Chaiwat Jatisatienr, Wilford Lie, Alison T. Ung, Brian W. Skelton, Allan H. White

Faculty of Science - Papers (Archive)

A new pentacyclic Stemona alkaloid, stemocurtisinol (3), with a pyrido[1,2-a]azepine A,B-ring system, and the known pyrrolo[1,2-a]azepine alkaloid oxyprotostemonine (4) have been isolated from a root extract of S. curtisii. The structure and relative stereochemistry of stemocurtisinol was determined by spectral data interpretation and X-ray crystallography. This compound is a diastereoisomer of oxystemokerrin and has the opposite configuration at C-4 and C-19. The individual alkaloid components showed significant larvicidal activity (IC₅₀ 4−39 ppm) on mosquito larvae (Anopheles minimus HO).

Synthesis Of (+)-(1r,2s,9s,9ar)-Octahydro-1h-Pyrrolo-[1,2-A]Azepine-1,2,9-Triol: A Potential Glycosidase Inhibitor, Karl B. Lindsay, Stephen G. Pyne

Faculty of Science - Papers (Archive)

The title compound was prepared as a potential glycosidase inhibitor. Key steps in the synthesis are vinyl epoxide aminolysis, ring-closing metathesis, cis-dihydroxylation and then ring closure.

Asymmetric Synthesis Of Polyfunctionalized Pyrrolidines And Related Alkaloids, Stephen G. Pyne, Andrew S. Davis, Nicole Gates, Joseph Hartley, Karl Lindsay, Theeraphan Machan, Minyan Tang

Faculty of Science - Papers (Archive)

This account describes our recent studies on the development of a general method of preparing polyfunctionalized pyrrolidine, indolizidine, pyrrolizidine and pyrrolo[1,2-a]azepines and their related alkaloids.

Landscape Management: Is It The Future?, R. J. Whelan

Faculty of Science - Papers (Archive)

As a Keynote Address at the 2004 Nature Conservation Council Conference, Bushfire in a Changing Environment - New Directions in Management, this paper argues that the landscape is a template with biodiversity assets, and human assets and bushfires overlaid. Two case studies, the Greater Glider and Eastern Bristlebird, are used to illustrate how the impact of bushfire on a species is contingent on it is distributed in the landscape, relative to the locations of its remnant habitat. Mitigation of bushfire effects, using fuel-reduction programs, is a process that also needs to be considered at a landscape scale, and has the …

The Ad 1607 Coastal Flood In The Bristol Channel And Severn Estuary: Historical Records From Devon And Cornwall (Uk), S. K. Haslett, Edward A. Bryant

Faculty of Science - Papers (Archive)

The 1607 coastal flood was a high magnitude event that may have been the result of either a storm surge or a tsunami wave(s). Contemporary accounts describe the impacts of the surge/wave at Appledore and Barnstaple in North Devon, and a 19'x' century comment exists for Hayle in. Cornwall. An examination restricted to these local accounts reveals that the surge altitude or tsunami run-up at Appledore, at the estuary mouth, exceeded 8.5 in OD (a surge/wave height in excess of 3.28 in, possibly lip to c. 7-8 in), and at Barnstaple, about 12 km up-estuary it reached 7.53 in OD …

Plasminogen Binding By Group A Streptococcal Isolates From A Tropical Region With Hyperendemic Streptococcal Skin Infection And A High Incidence Of Invasive Infection, F. C. Mckay, Jason D. Mcarthur, Martina L. Sanderson-Smith, S. Gardam, B. J. Currie, K. S. Sriprakash, P. K. Fagan, R. J. Towers, M. R. Batzloff, G. S. Chhatwal, Marie Ranson, Mark J. Walker

Faculty of Science - Papers (Archive)

Reports of resurgence in invasive group A streptococcal (GAS) infections come mainly from affluent populations with infrequent exposure to GAS. In the tropical Northern Territory (NT) of Australia, high incidence of invasive GAS disease is secondary to endemic skin infection; serotype M1 clones are rare in invasive infection; the diversity and level of exposure to GAS strains is high and no particular strains dominate. Expression of a plasminogen-binding group A streptococcal M-like protein (PAM) has been associated with skin infection in isolates elsewhere (Bessen, D., C.M. Sotir, T.M. Readdy, and S.K. Hollingshead.1996. J. Infect. Dis. 173:896-900) and subversion of the …

An Assessment Of Five Australian Polychaetes And Bivalves For Use In Whole-Sediment Toxicity Tests: Toxicity And Accumulation Of Copper And Zinc From Water And Sediment, C K. King, M C. Dowse, S L. Simpson, D F. Jolley

Faculty of Science - Papers (Archive)

The suitability of two polychaete worms, Australonereis ehlersi and Nephtys australiensis, and three bivalves, Mysella anomala, Tellina deltoidalis, and Soletellina alba, were assessed for their potential use in whole-sediment toxicity tests. All species except A. ehlersi, which could not be tested because of poor survival in water-only tests, survived in salinities ranging from 18‰ to 34‰ during the 96-hour exposure period. No mortality was observed in any of the species exposed to sediment compositions ranging from 100% silt to 100% sand for 10 days, thus demonstrating the high tolerance of the five species to a wide range of sediment types. …

Secure Multimedia Authoring With Dishonest Collaborators, N. P. Sheppard, R. Safavi-Naini, P. Ogunbona

Faculty of Informatics - Papers (Archive)

Many systems have been proposed for protecting the intellectual property of multimedia authors and owners from the public at large, who have access to the multimedia only after it is published. In this paper, we consider the problem of protecting authors' intellectual property rights from insiders, such as collaborating authors and producers, who interact with the creative process before publication. We describe the weaknesses of standard proof-of-ownership watermarking approaches against dishonest insiders, and propose several possible architectures for systems that avoid these weaknesses. We further show how these architectures can be adapted for fingerprinting in the presence of dishonest insiders.

Usability/User Interface Design In Agile Processes, A. Fuller

Faculty of Informatics - Papers (Archive)

The increasing popularity of the “agile” software development methods has prompted claims that such methods compromise the usability of the delivered product. However, this need not be the case. While some authors have suggested remedial extensions or additions that run in parallel with the chosen method, we believe that any agile method, properly applied, will produce software equally as useable as that produced by any other method.

The aim of this paper is twofold. Firstly we present a survey of many of the arguments made in the literature, thus bringing together a number of differing concerns. Then we set out …

A Comparison Of Drinking Water Contamination In Buried Slab Wells, Other Large-Diameter Wells, And Drilled Wells, Rita M. Gergely

Journal of the Iowa Academy of Science: JIAS

This study presents the results of a statewide water well survey conducted by the Iowa Department of Public Health from 1993 to 1995 to determine whether there were statistically significant differences between well water contamination in buried slab wells, other large-diameter wells, and drilled wells. Wells were sampled for total coliform bacteria, fecal coliform bacteria, nitrate, and atrazine. Staff collected water samples and completed a site survey at each well, which included an interview with the occupant or owner and actual observations of the wellhead and surrounding area.

The study included 293 buried slab wells, 287 other large-diameter wells, and …

The Impact Of White Pine (Pinus Strobus) On A Mollisol After Seven Decades Of Soil Development, Irina Kovda, Eric C. Brevik, Thomas E. Fenton, Maria Gerasimova

Journal of the Iowa Academy of Science: JIAS

Selected chemical, physical, and macro and micromorphological properties in two pedons of a Clarion soil (Fine-loamy, mixed, superactive, mesic Typic Hapludolls) formed in till parent material, one planted to white pines (Pinus strobus) for the past 75 years and the other to grass, were compared. The most obvious difference between the two was the increased biological activity under pines; the variety and quantity of excrements suggested the activity of soil microfauna and variability of species resulted in finer and better aggregation of biological origin (crumbs and granules), numerous excrements in voids, and higher total porosity under pines. The matrix was …

Flow Cytometry Used To Assess Genetic Damage In Frogs From Farm Ponds, Bartholomew L. Bly, Melinda G. Knutson, Mark B. Sandheinrich, Brian R. Gray, Dean A. Jobe

Journal of the Iowa Academy of Science: JIAS

Flow cytometry (FC) is a laboratory method used to detect genetic damage induced by environmental contaminants and other stressors in animals, including amphibians. We tested FC methods on three species of ranid frogs collected from farm ponds and natural wetlands in southeastern Minnesota. We compared FC metrics for Rana clamitans between ponds with direct exposure to agricultural contaminants and reference (unexposed) ponds. Concentrations of atrazine in water from our farm ponds ranged from 0.04 to 0.55 ppb. We found that R. clamitans from exposed ponds had DNA content similar to frogs from unexposed ponds. Pond-averaged C-values (a measure of DNA …

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Index For The Journal Of The Iowa Academy Of Science Volume 111

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Early Work In Database Research On Schema Mapping/Merging/Transformation, Semantic Heterogeneity, And Use Of Ontology And Description Logics For Schematic And Semantic Integration, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.

Attractors From One Dimensional Lorenz-Like Maps, Youngna Choi

Department of Applied Mathematics and Statistics Faculty Scholarship and Creative Works

In this paper we study the properties of expanding maps with a single discontinuity on a closed interval and the resultant dynamics. For such a map, there exists a compact invariant subset which shares a lot of common properties with classical attractors such as the topological transitivity of the restricted map and the density of the periodic points. The invariant set, with more conditions on the boundary, can be shown to have an isolating neighborhood, hence is a chaotic attractor in the strong sense. Not all such maps derive trapping regions, yet by perturbation, those non-attractors can be made to …

Controlling Wound Healing Through Debridement, M. A. Jones, Baojun Song, D. M. Thomas

Department of Applied Mathematics and Statistics Faculty Scholarship and Creative Works

The formation of slough (dead tissue) on a wound is widely accepted as an inhibitor to natural wound healing. In this article, a system of differential equations that models slough/wound interaction is developed. We prove a threshold theorem that provides conditions on the amount of slough to guarantee wound healing. As a state-dependent time scale, debridement (the periodic removal of slough) is used as a control. We show that closure of the wound can be reached in infinite time by debriding.

Introduction To Special Section: Preparing For The San Andreas Fault Observatory At Depth, Stephen Hickman, Mark D. Zoback, William Ellsworth

United States Geological Survey: Staff Publications

The San Andreas Fault Observatory at Depth (SAFOD) is a comprehensive project to drill into the hypocentral zone of repeating M ~ 2 earthquakes on the San Andreas Fault at a depth of about 3 km. The goals of SAFOD are to establish a multi-stage geophysical observatory in close proximity to these repeating earthquakes, to carry out a comprehensive suite of downhole measurements in order to study the physical and chemical conditions under which earthquakes occur and to exhume rock and fluid samples for extensive laboratory studies. In the vicinity of SAFOD, the San Andreas is moving through a combination …

Stress-Induced, Time-Dependent Fracture Closure At Hydrothermal Conditions, N. M. Beeler, S. H. Hickman

United States Geological Survey: Staff Publications

Time-dependent closure of fractures in quartz was measured in situ at 22–530 °C temperature and 0.1–150 MPa water pressure. Unlike previous crack healing and rock permeability studies, in this study, fracture aperture is monitored directly and continuously using a windowed pressure vessel, a long-working-distance microscope, and reflectedlight interferometry. Thus the fracture volume and geometry can be measured as a function of time, temperature, and water pressure. Relatively uniform closure occurs rapidly at temperatures and pressures where quartz becomes significantly soluble in water. During closure the aperture is reduced by as much as 80% in a few hours. We infer that …

Genetic Identification Of Spotted Owls, Barred Owls, And Their Hybrids: Legal Implications Of Hybrid Identity, Susan M. Haig, Thomas D. Mullins, Eric D. Forsman, Pepper W. Trail, Liv Wennerberg

United States Geological Survey: Staff Publications

Recent population expansion of Barred Owls (Strix varia) into western North America has led to concern that they may compete with and further harm the Northern Spotted Owl (S. occidentalis caurina), which is already listed as threatened under the U.S. Endangered Species Act (ESA). Because they hybridize, there is a legal need under the ESA for forensic identification of both species and their hybrids. We used mitochondrial control-region DNA and amplified fragment-length polymorphism (AFLP) analyses to assess maternal and biparental gene flow in this hybridization process. Mitochondrial DNA sequences (524 base pairs) indicated large divergence between …

Can We Predict Joint Effects Of Hypoxia And Metals On Fish Survival?, Michael C. Newman

VIMS Books and Book Chapters

Fish are suddenly exposed to hypoxic conditions during diverse events such as seiche- or turnover-related water movements, bottom water release from reservoirs, ice-over of eutrophic arctic lakes, and rapid shifts in respiration: photosynthesis associated with cultural eutrophication. In each case, chemical equilibria established under hypoxic conditions that result in metal dissolution and accumulation suddenly shift toward chemical equilibria of oxic conditions. Critical changes in speciation include those determining the free ion activity that, as expressed by the Free Ion Activity Model (FIAM), is often the most bioactive form of a dissolved metal. Metal phase can also change rapidly and, in …

Subspecific Relationships And Genetic Structure In The Spotted Owl, Susan M. Haig, Thomas D. Mullins, Eric D. Forsman

United States Geological Survey: Staff Publications

Hierarchical genetic structure was examined in the three geographically-defined subspecies of spotted owl (Strix occidentalis) to define relationships among subspecies and quantify variation within and among regional and local populations. Sequences (522 bp) from domains I and II of the mitochondrial control region were analyzed for 213 individuals from 30 local breeding areas. Results confirmed significant differences between northern spotted owls and the other traditional geographically defined subspecies but did not provide support for subspecific level differences between California and Mexican spotted owls. Divergence times among subspecies estimated with a 936 bp portion of the cytochrome b gene …

Residues And Tame Symbols On Toroidal Varieties, Ivan Soprunov

Mathematics and Statistics Faculty Publications

We introduce a new approach to the study of a system of algebraic equations in (C) whose Newton polytopes have sufficiently general relative positions. Our method is based on the theory of Parshin’s residues and tame symbols on toroidal varieties. It provides a uniform algebraic explanation of the recent result of Khovanskii on the product of the roots of such systems and the Gel’fond–Khovanskii result on the sum of the values of a Laurent polynomial over the roots of such systems, and extends them to the case of an algebraically closed field of arbitrary characteristic.

Advances In The Geology Of The Tobacco Root Mountains, Montana, And Their Implications For The History Of The Northern Wyoming Province, Tekla A. Harms, John B. Brady, H. Robert Burger, John T. Cheney

Geosciences: Faculty Publications

Integrated studies by Keck Geology Consortium participants have generated many new insights into the Precambrian geology of the Tobacco Root Mountains. We have clarified the tectonic setting and origin of two suites of metamorphic rocks: (1) a quartzofeldspathic gneiss complex with associated metasupracrustal rocks (the combined Indian Creek and Pony–Middle Mountain Metamorphic Suites) that originated in a continental arc setting between 3.35 and 3.2 Ga with subsequent sedimentation and (2) mafic metavolcanic rocks with intercalated metasedimentary rocks (the Spuhler Peak Metamorphic Suite) from a suprasubduction zone ophiolite or backarc basin possibly of Proterozoic age. A poorly preserved metamorphic event at …