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Full-Text Articles in Social and Behavioral Sciences

Endogenous Redox Activity In Mouse Spermatozoa And Its Role In Regulating The Tyrosine Phosphorylation Events Associated With Sperm Capacitation, Heath W. Ecroyd, Russell C. Jones, Robert J. Aitken Jan 2003

Endogenous Redox Activity In Mouse Spermatozoa And Its Role In Regulating The Tyrosine Phosphorylation Events Associated With Sperm Capacitation, Heath W. Ecroyd, Russell C. Jones, Robert J. Aitken

Faculty of Science - Papers (Archive)

We investigated the role of endogenous redox activity in regulating the signal transduction pathway leading to tyrosine phosphorylation in mouse spermatozoa. Endogenous redox activity was monitored using a luminol-peroxidase chemiluminescent probe. Chemiluminescence increased in spermatozoa that were actively undergoing cAMP-mediated tyrosine phosphorylation events associated with capacitation and was inhibited in a dose-dependent manner by addition of catalase or diphenylene iodonium, both of which also inhibited tyrosine phosphorylation within the cell at points downstream of cAMP. Excluding bicarbonate from the incubation medium reduced the redox activity of sperm by 80-90% and dramatically reduced tyrosine phosphorylation. This study provides the first evidence …


Arts And Sciences Newsletter, Volume 6, Issue 4, College Of Arts & Sciences Jan 2003

Arts And Sciences Newsletter, Volume 6, Issue 4, College Of Arts & Sciences

Arts and Sciences Newsletters

No abstract provided.


The Planet, 2003, Winter, Kate Koch, Huxley College Of The Environment, Western Washington University Jan 2003

The Planet, 2003, Winter, Kate Koch, Huxley College Of The Environment, Western Washington University

The Planet

No abstract provided.


Huxley Horizon, 2003, Winter, Huxley College Of The Environment, Western Washington University Jan 2003

Huxley Horizon, 2003, Winter, Huxley College Of The Environment, Western Washington University

Historical Collection of Huxley Newsletters

No abstract provided.


Action Education In Land Use Decisions: Student Views On Urbanization And Farmland Loss, Mindi Schneider, Charles A. Francis, Dick Esseks Jan 2003

Action Education In Land Use Decisions: Student Views On Urbanization And Farmland Loss, Mindi Schneider, Charles A. Francis, Dick Esseks

CARI Extension and Education Materials for Sustainable Agriculture

Loss of prime farmland is a serious concern in the United States and around the globe. With rapid urban population increases, the activities and perceived needs of concentrated groups of people result in the swallowing of some of the most fertile lands in this country. Today we have just under 2 acres of productive farmland per person in the United States. Given the current population growth rate due to births and immigration, plus the present rate of farmland loss, World Watch Institute estimates that we will have about 0.6 acres or one-third as much farmland available per person by 2055--a …


Small Heat-Shock Proteins And Clusterin: Intra- And Extracellular Molecular Chaperones With A Common Mechanism Of Action And Function, J. A. Carver, A. Rekas, D. C. Thorn, M. R. Wilson Jan 2003

Small Heat-Shock Proteins And Clusterin: Intra- And Extracellular Molecular Chaperones With A Common Mechanism Of Action And Function, J. A. Carver, A. Rekas, D. C. Thorn, M. R. Wilson

Faculty of Science - Papers (Archive)

Small heat-shock proteins (sHsps) and clusterin are molecular chaperones that share many functional similarities despite their lack of significant sequence similarity. These functional similarities, and some differences, are discussed. sHsps are ubiquitous intracellular proteins whereas clusterin is generally found extracellularly. Both chaperones potently prevent the amorphous aggregation and precipitation of target proteins under stress conditions such as elevated temperature, reduction and oxidation. In doing so, they act on the slow off-folding protein pathway. The conformational dynamism and aggregated state of both proteins may be crucial for their chaperone function. Subunit exchange is likely to be important in regulating chaperone action; …


Environmental (Re)Education And Local Environmental Knowledge: Statutory Ground-Based Monitoring And Pastoral Culture In Central Australia, Nicholas J. Gill Jan 2003

Environmental (Re)Education And Local Environmental Knowledge: Statutory Ground-Based Monitoring And Pastoral Culture In Central Australia, Nicholas J. Gill

Faculty of Science - Papers (Archive)

Ground-based monitoring of rangeland condition is common in Australian pastoral administration systems. In the Northern Territory, such monitoring is officially seen as a key plank of sustainable pastoral land use. In the NT and elsewhere, these monitoring schemes have sought to increase participation by pastoralists. Involvement of pastoralists in monitoring is theoretically an educative process that will cause pastoralists to more critically examine their management practices. Critical perspectives on the relationship between rangelands science/extension and pastoralist knowledge systems and concerns, however, suggest that pastoralists’ reception of such monitoring schemes will be influenced by a range of social contexts, including the …


Stemocurtisine, The First Pyrido[1,2-A]Azapine Stemona Alkaloid, Pitchaya Mungkornasawakul, Stephen G. Pyne, Araya Jatisatienr, Damrat Supyen, Wilford Lie, Alison T. Ung, Brian W. Skelton, Allan H. White Jan 2003

Stemocurtisine, The First Pyrido[1,2-A]Azapine Stemona Alkaloid, Pitchaya Mungkornasawakul, Stephen G. Pyne, Araya Jatisatienr, Damrat Supyen, Wilford Lie, Alison T. Ung, Brian W. Skelton, Allan H. White

Faculty of Science - Papers (Archive)

A new pentacyclic stemona alkaloid, stemocurtisine (2), with a novel pyrido[1,2-a]azapine A,B-ring system, has been isolated from a root extract of Stemona curtisii. The structure and relative stereochemistry was determined by spectral data interpretation and X-ray crystallography.


An Assessment Of Water Quality In Ensign Hollow, Clayton And Fayette Counties, In Northeast Iowa, Rick Klann, Jaime Platts Jan 2003

An Assessment Of Water Quality In Ensign Hollow, Clayton And Fayette Counties, In Northeast Iowa, Rick Klann, Jaime Platts

Journal of the Iowa Academy of Science: JIAS

Water quality and benthic invertebrates in the Ensign Hollow watershed, southwestern Clayton County and southeastern Fayette County, Iowa, were monitored from 2000 to 2001. Measurements of physical and chemical parameters of water quality, as well as analysis of benthic invertebrates, all indicated that streams of the Ensign Hollow watershed were exposed to slight organic pollution. Furthermore, the greatest threat to this watershed appeared to be sedimentation introduced through runoff.


Cathodoluminescence As A Means For Distinguishing Hydrothermal From Pre-Hydrothermal Quartz In Sulfide-Bearing Mineral Deposits On The Northern Fringe Of The Upper Mississippi Valley Zinc-Lead District, Ne Iowa And Sw Wisconsin, Paul L. Garvin Jan 2003

Cathodoluminescence As A Means For Distinguishing Hydrothermal From Pre-Hydrothermal Quartz In Sulfide-Bearing Mineral Deposits On The Northern Fringe Of The Upper Mississippi Valley Zinc-Lead District, Ne Iowa And Sw Wisconsin, Paul L. Garvin

Journal of the Iowa Academy of Science: JIAS

Sulfide-bearing mineral deposits, located on the northern fringe of the Upper Mississippi Valley Zinc-Lead District, are contained in early Ordovician carbonate rocks that are extensively silicified and dolomitized. Some silica and dolomite appear to be products of the hydrothermal processes that also formed fracture-filling and cavity-lining sulfides and other cogenetic minerals; other silica and dolomite appear to result from low-temperature, pre-hydrothermal regional diagenesis. Distinguishing hydrothermal quartz (jasperoid) from pre-hydrothermal quartz (chert) solely by hand specimen and thin section petrography is difficult because these two types of mineralization are often intimately associated with each other. Polished slabs from several of these …


Salt Tolerance Of Sunflower And Lettuce In Cultivated And Uncultivated Grass Soil, Steven H. Emerman, Emily M. Kinsinger Jan 2003

Salt Tolerance Of Sunflower And Lettuce In Cultivated And Uncultivated Grass Soil, Steven H. Emerman, Emily M. Kinsinger

Journal of the Iowa Academy of Science: JIAS

We tested two hypotheses: 1) whether a vegetable crop will show greater growth under a given salinity treatment in an uncultivated grass soil than a cultivated soil and 2), if so, whether the greater growth is due to the occasional presence of relatively fresh water in macropores or the interaction between salinity and hypoxia in a soil without significant macropores. A previous study suggested uptake from. macropores was significant only for crops with high root water potential (Emerman and Dawson 1997). Hence, in this study, 21 miniature crops were grown in a greenhouse, and the ratio of root dry weight …


Recent Observations Of The Distribution And Status Of Freckled Madtom And First Record Of Spotted Gar In Iowa, Melvin C. Bowler Jan 2003

Recent Observations Of The Distribution And Status Of Freckled Madtom And First Record Of Spotted Gar In Iowa, Melvin C. Bowler

Journal of the Iowa Academy of Science: JIAS

The distribution and status of Iowa's fishes were last extensively described in Iowa Fish and Fishing (Harlan et al. 1987). Since then, numerous fish collections have been made in Iowa's interior and bordering rivers and streams. In this paper, I describe recent collections of freckled mad tom (Noturus nocturnus) and spotted gar (Lepisosteus oculatus) from the Upper Mississippi. River (UMR). Six specimens of N. nocturnus were collected from Pool 13 of the UMR in 2001. Although the first documented specimens of N. nocturnus in Iowa were collected in the English River in 1984, few collections have been made throughout the …


Index For The Journal Of The Iowa Academy Of Science Volume 110 And Change Of Editor Jan 2003

Index For The Journal Of The Iowa Academy Of Science Volume 110 And Change Of Editor

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


People In Nature: Environmental History Of The Kennebec River, Maine, Daniel J. Michor Jan 2003

People In Nature: Environmental History Of The Kennebec River, Maine, Daniel J. Michor

Electronic Theses and Dissertations

The quality of a river affects the tributaries, lakes, and estuary it feeds; it affects the wildlife and vegetation that depend on the river for energy, nutrients, and habitat, and also affects the human community in the form of use, access, pride, and sustainability. In an age of mass consumerism and materialism, dwindling natural resources and wild spaces, and advanced technology, the ability to make a living and at the same time enjoy the benefits of rural living is increasingly difficult. Using the entire Kennebec River watershed as the scale of investigation with particular focus on the river corridor itself, …


Digitization In An Archival Environment, Sally Mckay Jan 2003

Digitization In An Archival Environment, Sally Mckay

E-JASL 1999-2009 (Volumes 1-10)

Introduction

Cultural institutions such as museums, libraries, archives, and historical societies house remarkable collections of cultural artifacts. It is the responsibility of the staff working for those institutions to preserve, protect and provide responsible stewardship for the materials, and to the best of their ability, provide continued long-term access (Russell, 2000).

Advances in technology allow institutions to provide expanded access and education; however, there are important priorities that must be addressed prior to embarking on a digital conversion project.

Digitization in an archival environment includes taking a physical object or analog item, such as an art object, a tape recording, …


Cover - Table Of Contents Jan 2003

Cover - Table Of Contents

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Semantic Web Processes, Jorge Cardoso, Amit P. Sheth Jan 2003

Semantic Web Processes, Jorge Cardoso, Amit P. Sheth

Kno.e.sis Publications

No abstract provided.


Learning Continuous Latent Variable Models With Bregman Divergences, Shaojun Wang, Dale Schuurmans Jan 2003

Learning Continuous Latent Variable Models With Bregman Divergences, Shaojun Wang, Dale Schuurmans

Kno.e.sis Publications

We present a class of unsupervised statistical learning algorithms that are formulated in terms of minimizing Bregman divergences— a family of generalized entropy measures defined by convex functions. We obtain novel training algorithms that extract hidden latent structure by minimizing a Bregman divergence on training data, subject to a set of non-linear constraints which consider hidden variables. An alternating minimization procedure with nested iterative scaling is proposed to find feasible solutions for the resulting constrained optimization problem. The convergence of this algorithm along with its information geometric properties are characterized.


Web Service: Been There, Done That?, Steffen Staab, Will Van Der Aalst, V. Richard Benjamins, Amit P. Sheth, John A. Miller, Chistoph Bussler, Alexander Maedche, Dieter Fensel, Dennis Gannon Jan 2003

Web Service: Been There, Done That?, Steffen Staab, Will Van Der Aalst, V. Richard Benjamins, Amit P. Sheth, John A. Miller, Chistoph Bussler, Alexander Maedche, Dieter Fensel, Dennis Gannon

Kno.e.sis Publications

Web services can be defined as loosely coupled, reusable software components that semantically encapsulate discrete functionality and are distributed and programmatically accessible over standard Internet protocols. Web services have received a lot of hype, the reasons for which are not easily determined. Some of their benefits might even seem to waste away, once we touch on the nitty-gritty details, because Web services per se do not offer a solution to underlying problems. The contributions included in this section delve into some of these issues, including: pitfalls of workflow issues; structuring procedural knowledge into problem-solving methods; discussing how a low initial …


Semantic N-Gram Language Modeling With The Latent Maximum Entropy Principle, Shaojun Wang, Dale Schuurmans, Fuchun Peng, Yunxin Zhao Jan 2003

Semantic N-Gram Language Modeling With The Latent Maximum Entropy Principle, Shaojun Wang, Dale Schuurmans, Fuchun Peng, Yunxin Zhao

Kno.e.sis Publications

We describe a unified probabilistic framework for statistical language modeling-the latent maximum entropy principle-which can effectively incorporate various aspects of natural language, such as local word interaction, syntactic structure and semantic document information. Unlike previous work on maximum entropy methods for language modeling, which only allow explicit features to be modeled, our framework also allows relationships over hidden features to be captured, resulting in a more expressive language model. We describe efficient algorithms for marginalization, inference and normalization in our extended models. We then present experimental results for our approach on the Wall Street Journal corpus.


Introducing The Global Diffusion Of The Internet Series, Peter Wolcott, Seymour E. Goodman Jan 2003

Introducing The Global Diffusion Of The Internet Series, Peter Wolcott, Seymour E. Goodman

Information Systems and Quantitative Analysis Faculty Publications

Many genes can play a role in multiple biological processes or molecular functions. Identifying multifunctional genes at the genome-wide level and studying their properties can shed light upon the complexity of molecular events that underpin cellular functioning, thereby leading to a better understanding of the functional landscape of the cell. However, to date, genome-wide analysis of multifunctional genes (and the proteins they encode) has been limited. Here we introduce a computational approach that uses known functional annotations to extract genes playing a role in at least two distinct biological processes. We leverage functional genomics data sets for three organisms—H. sapiens, …


Applications Of Airborne Laser Scanning To Manage Coastal Acid Sulfate Soils Within The Broughton Creek Floodplain, Marcus Morgan, Warwick Papworth, Peter Aney, John Perry, Buddhima Indraratna Jan 2003

Applications Of Airborne Laser Scanning To Manage Coastal Acid Sulfate Soils Within The Broughton Creek Floodplain, Marcus Morgan, Warwick Papworth, Peter Aney, John Perry, Buddhima Indraratna

Faculty of Science - Papers (Archive)

Airborne Laser Scanning (ALS) Was first used in 1993 by Geodan Geodesie B. V. as a cheaper alternative in the collection of spatial information than traditional survey methods and photogrammetry. ALS has become important in creating Digital Terrain Models (DTM) with high precision at a far lower cost to other methods. Shoalhaven City Council employed ALS in May 200 I for the purpose of obtaining detailed survey information within budgetary constraints. The aim Was to determine the effectiveness of using ALS for coastal and environmental management by testing the accuracy of ground level points against traditionally surveyed points.

Coastal Acid …


Changing Ecological Concerns In Rock-Art Subject Matter Of North Australia's Keep River Region, Paul Tacon, Ken Mulvaney, Sven Ouzman, Richard L. Fullagar, Lesley M. Head, Paddy Carlton Jan 2003

Changing Ecological Concerns In Rock-Art Subject Matter Of North Australia's Keep River Region, Paul Tacon, Ken Mulvaney, Sven Ouzman, Richard L. Fullagar, Lesley M. Head, Paddy Carlton

Faculty of Science - Papers (Archive)

The Keep River region has a complex body of engraved and painted rock-art, distinct from but with links to regions to the east, west and south. At least four major periods of figurative rock-art have been identified with differing subject matters and ages. Significant changes in depictions of human figures and animals are evident, reflecting shifts in emphasis associated with ecological concerns and environmental change. We flesh out the relative rock-art chronology by highlighting these changes, from worlds dominated by humans to those dominated by mammals and birds, and finally to a recent world of reptiles and humans. Symbolic aspects …


Diagenesis And Geochemistry Of Porites Corals From Papua New Guinea: Implications For Paleoclimate Reconstruction, Helen V. Mcgregor, M Gagan Jan 2003

Diagenesis And Geochemistry Of Porites Corals From Papua New Guinea: Implications For Paleoclimate Reconstruction, Helen V. Mcgregor, M Gagan

Faculty of Science - Papers (Archive)

No abstract provided.


Evolution Of Chemical Contaminant And Toxicology Studies, Part 1 - An Overview, Dianne F. Jolley, Glennys A. O'Brien, Robert John Morrison Jan 2003

Evolution Of Chemical Contaminant And Toxicology Studies, Part 1 - An Overview, Dianne F. Jolley, Glennys A. O'Brien, Robert John Morrison

Faculty of Science - Papers (Archive)

The study of environmental chemical contaminants and their toxicological effects has changed dramatically over the last 50 years. Initially studies concentrated on trying to identify what contaminants were actually present and to develop quantitative methods to determine the concentrations (total) present. Health impacts were often investigated independently in medical research centres. With improving analytical techniques, studies of the speciation of contaminants began and the specific forms that were creating the major problems were gradually identified. Continuing improvements in analytical chemistry, together with a move towards more integrated and multidisciplinary research now sees chemists, biologists, toxicologists and health researchers working closely …


Evolution Of Chemical Contaminant And Toxicology Studies, Part 2- Case Studies Of Selenium And Arsenic, Glennys O'Brien, Dianne Jolley, Robert John Morrison Jan 2003

Evolution Of Chemical Contaminant And Toxicology Studies, Part 2- Case Studies Of Selenium And Arsenic, Glennys O'Brien, Dianne Jolley, Robert John Morrison

Faculty of Science - Papers (Archive)

As the second of a two part series discussing the evolution of the field of environmental toxicology, this paper presents two case studies: selenium and arsenic. Developments over several decades in the understanding of the behaviour of arsenic and selenium in different chemical forms in various compartments of the environment are discussed. Selenium was initially thought to be toxic, but later investigations showed it to be an essential micronutrient with a variety of biochemical functions, and, importantly, that there is a very narrow gap between the essential and the toxic body burden. Arsenic, on the other hand, has not yet …


Application Of Rusle For Erosion Management In A Coastal Catchment, Southern Nsw, A. D. Simms, C. D. Woodroffe, B. G. Jones Jan 2003

Application Of Rusle For Erosion Management In A Coastal Catchment, Southern Nsw, A. D. Simms, C. D. Woodroffe, B. G. Jones

Faculty of Science - Papers (Archive)

River catchments are dynamic and vulnerable systems that can change markedly when exposed to human impact. Changes induced since European settlement in Australia are of particular interest because impacts can be almost impossible to reverse. A measure of catchment degradation may be determined using accumulation in lakes. Along the east coast of New South Wales, both the rate of sediment infill and the stage of infill reached differ between coastal lagoons as a function of physical characteristics within their catchments, including the erosive power of rainfall, the intrinsic susceptibility of the soils to erosion, as well as the combined effect …


Checklist Of Instructions For Authors Jan 2003

Checklist Of Instructions For Authors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Back Cover Jan 2003

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.


Submersed Aquatic Vegetation Trends In Impounded And Backwater Habitat Types Of Pool 13, Upper Mississippi River System: 1994-2000, Theresa A. Blackburn, Daniel J. Kirby Jan 2003

Submersed Aquatic Vegetation Trends In Impounded And Backwater Habitat Types Of Pool 13, Upper Mississippi River System: 1994-2000, Theresa A. Blackburn, Daniel J. Kirby

Journal of the Iowa Academy of Science: JIAS

Submersed aquatic vegetation (SAV) was sampled from 1994-2000 at fixed sires along established transects in Pool 13 of the Upper Mississippi River System (UMRS), as part of the Long Term Resource Monitoring Program (LTRMP). These data were used to quantify the annual percent frequency of occurrence and mean relative density of SAV within three backwaters (Brown's Lake, Savanna Bay, and Spring Lake) and the impounded area of Pool 13. This investigation used Spearman rank correlation to assess the strength of bivariate relationships between measurements of SAV abundance and biological, physical, and hydrological variables at fixed water quality monitoring sites within …