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Inquiry: The University Of Arkansas Undergraduate Research Journal - Volume 3 - Fall 2002, Inquiry Editors Jan 2002

Inquiry: The University Of Arkansas Undergraduate Research Journal - Volume 3 - Fall 2002, Inquiry Editors

Inquiry: The University of Arkansas Undergraduate Research Journal

No abstract provided.

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Native Plants: The Preservation And Restoration Of Native Plants In Designed Landscapes In Northwest Arkansas, Janet Coleman Jan 2002

Native Plants: The Preservation And Restoration Of Native Plants In Designed Landscapes In Northwest Arkansas, Janet Coleman

Inquiry: The University of Arkansas Undergraduate Research Journal

A decline in Northwest Arkansas's native plant population has occurred over the past 50 years, as documented by the U.S. Forest Service in the Ozark-Ouachita Highlands Assessment. This decline has been caused by increased human development in natural areas and the replacement of native plants with exotic, non-native plants. As a result, a generation has grown up not knowing what an Ozark wake Robin trillium (Trillium pusillum var. ozarkanum) or Blood root (Sanguinaria canadensis) Look like, because these plants are difficult to find in nature, are not commonly grown in designed landscapes, and are Largely unavailable in garden centers. The …

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Characterization Of Wound-Inducible Genes Encoding Enzymes For Terpenoid Biosynthesis In Medicago Truncatula, Mandy M. Cox Jan 2002

Characterization Of Wound-Inducible Genes Encoding Enzymes For Terpenoid Biosynthesis In Medicago Truncatula, Mandy M. Cox

Inquiry: The University of Arkansas Undergraduate Research Journal

In addition to having numerous applications as food flavorings and pharmaceuticals, terpenoids are an important class of defensive compounds that can accumulate in plants after pathogen infection or injury by insects. Sequences of DNA encoding putative terpene synthases and an oxidosqualene synthase, isolated from insect-damaged Medicago truncatula leaves, were selected from an expressed sequence tag (EST) database. The eDNA clones were used as radiolabeled probes to analyze gene expression in leaves treated with factors known to trigger a defense response in plants. Transcript levels for all of the genes examined increased in response to artificial wounding, insect herbivory, and methyl …

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Properties Of Modified Tryptophans In A Membrane- Spanning Channel, Erin M. Scherer Jan 2002

Properties Of Modified Tryptophans In A Membrane- Spanning Channel, Erin M. Scherer

Inquiry: The University of Arkansas Undergraduate Research Journal

An emerging concept in biology assigns the amino acid tryptophan specific roles at the membrane/water interface that help to determine the conformation and biological function of membrane-spanning proteins. Previous studies involving the antibiotic model system gramicidin A (gA) have illustrated the importance of the indole ring of tryptophan (Trp) in anchoring proteins to a bilayer membrane and promoting ionic currents. To further investigate these phenomena, derivatives of Trp that have lost hydrogen-bonding ability (1-methyl-Trp ), have an altered dipole moment (7-aza-Trp), or both (1-methyl-7-azaTrp) were chosen for incorporation into gA. Gramicidin analogues that incorporate these modified Trps were then analyzed …

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Extraction Of Silymarin Compounds From Milk Thistle (Silybum Marianum) Seed Using Hot, Liquid Water As The Solvent, J.F. Alvarez Barreto Jan 2002

Extraction Of Silymarin Compounds From Milk Thistle (Silybum Marianum) Seed Using Hot, Liquid Water As The Solvent, J.F. Alvarez Barreto

Inquiry: The University of Arkansas Undergraduate Research Journal

High value specialty chemicals are usually obtained from natural products by extracting with generally regarded as safe (GRAS) solvents. Because organic solvents are quite often used, high operating and disposal costs often occur. When compared to traditional solvents, water can be viewed as an interesting alternative because of its low operating and disposal costs. Milk thistle contains compounds (taxifolin, silychristin, silydianin, silybinin A and silybinin B) that display hepatoxic protection properties. This paper examines the batch extraction of silymarin compounds from milk thistle seed meal in 50'C, 70'C, 85'C and 100'C water as a function of time. For taxifolin, silychristin, …

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Stimulation And Modeling Of Pond Formations On The Asteroid 433 Eros, Justin Thompson Jan 2002

Stimulation And Modeling Of Pond Formations On The Asteroid 433 Eros, Justin Thompson

Inquiry: The University of Arkansas Undergraduate Research Journal

"Ponds" are surface features that appear to be the result of the deposition of finer material on the asteroid's regolith, the layer of loose sediment that blankets the entire asteroid. Ponds were discovered by the NEAR Shoemaker spacecraft in January, 2001, on the asteroid 433 Eros. The objective of experimentation is to simulate the development of these ponds in the Andromeda planetary sciences environmental chamber. The Andromeda Chamber offers a unique ability to simulate surface environments that occur on Eros. The chamber was used to simulate the processes that occur as Eros emits gas through its outer surface, including the …

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86th Annual Meeting, 2002. Secretary's Report And Financial Statement, Academy Editors Jan 2002

86th Annual Meeting, 2002. Secretary's Report And Financial Statement, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Journal Of The Arkansas Academy Of Science - Volume 56 2002, Academy Editors Jan 2002

Journal Of The Arkansas Academy Of Science - Volume 56 2002, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Millipeds (Arthropoda: Diplopoda) Of The Ark-La-Tex. Ii. Distributional Records For Some Species Of Western And Central Arkansas And Easter And Southeastern Oklahoma, Chris T. Mcallister, Rowland M. Shelley, James T. Mcallister Iii Jan 2002

Millipeds (Arthropoda: Diplopoda) Of The Ark-La-Tex. Ii. Distributional Records For Some Species Of Western And Central Arkansas And Easter And Southeastern Oklahoma, Chris T. Mcallister, Rowland M. Shelley, James T. Mcallister Iii

Journal of the Arkansas Academy of Science

We collected millipeds between November 2001 and March 2002 at several sites in the Ouachita Provinces of western (Garland, Hot Spring, Pike, and Polk counties) and central Arkansas (Pulaski County) and the Ouachita and Kiamichi Provinces of southeastern Oklahoma (LeFlore and McCurtain counties). The following millipeds were found: Eurymerodesmus dubius, Auturus louisianus louisianus, Pseudopolydesmus pinetorum, and Cambala minor in Garland County; Eurymerodesmus sp., A. I. louisianus, P. pinetorum, and juveniles of the family Parajulidae (tribe Aniulini) from Hot Spring County; E. dubius, A. I. louisianus, and juveniles of the family Cleidogonidae from Pike County; Brachycybe lecontei, A. I. louisianus, Abacion …

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Distributions And Geographical Relationships Of The Polygyrid Land Snails (Mollusca, Gastropoda, Polygyridae) Of Arkansas, Gerald E. Walsh, Brian F. Coles Jan 2002

Distributions And Geographical Relationships Of The Polygyrid Land Snails (Mollusca, Gastropoda, Polygyridae) Of Arkansas, Gerald E. Walsh, Brian F. Coles

Journal of the Arkansas Academy of Science

The Arkansas distributions of land mollusks of the family Polygyridae are presented based on the results of a state-wide survey and a critical review of published and unpublished locality records. Six of the 45 species previously recorded for Arkansas are excluded because they were misidentified, do not have established populations in the state, or are found only as fossils. Four others are not mapped because of a lack of recent distributional data or because the specific status of a form is unclear. There is a predominant pattern of occurrence limited to the northern, northwestern, or western parts of the state. …

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Harvey E. Barton: In Memoriam, Lynita M. Cooksey, Larry A. Olson Jan 2002

Harvey E. Barton: In Memoriam, Lynita M. Cooksey, Larry A. Olson

Journal of the Arkansas Academy of Science

No abstract provided.

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Publication Policies And Suggestions For Authors, Academy Editors Jan 2002

Publication Policies And Suggestions For Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Development Of A Yeast Biosensor Strain For The Identification Of Genotoxic Compounds, Robin M. Reed Jan 2002

Development Of A Yeast Biosensor Strain For The Identification Of Genotoxic Compounds, Robin M. Reed

Inquiry: The University of Arkansas Undergraduate Research Journal

Advances in combinatorial chemistry have provided the pharmaceutical industry with innumerable lead compounds that could potentially serve as therapeutic agents. One of the challenges in the further development of such compounds is to rapidly, yet inexpensively, distinguish those that have undesirable effects such as genotoxicity. Thus, a simple biological assay that would permit the identification of potential DNA mutagens, and be adaptable to high-throughput technologies would be cost effective in screening such lead compounds. The current methods use the Ames and SOS tests involving prokaryotic organisms, while systems that utilize mammalian cell culture and/or animal testing are time-consuming and expensive. …

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Extraction Of Silymarin Compounds From Milk Thistle (Silybum Marianum) Seed Using Hot, Liquid Water As The Solvent, J. F. Alvarez Barreto, D. Julie Carrier, E. C. Clausen Jan 2002

Extraction Of Silymarin Compounds From Milk Thistle (Silybum Marianum) Seed Using Hot, Liquid Water As The Solvent, J. F. Alvarez Barreto, D. Julie Carrier, E. C. Clausen

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

High-value specialty chemicals are usually obtained from natural products by extracting with generally regarded as safe (GRAS) solvents. Because organic solvents are quite often used, high operating and disposal costs occur. When compared to traditional solvents, water is an interesting alternative because of its low operating and disposal costs. Milk thistle contains compounds (taxifolin, silychristin, silydianin, silybinin A, and silybinin B) that display hepatoxic protection properties. This paper examines the batch extraction of silymarin compounds from milk thistle seed meal in 50°C, 70°C, 85°C and 100°C water as a function of time. For taxifolin, silychristin, silybinin A, and silybinin B, …

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Identifying Safety Strategies For On-Farm Grain Bins Using Risk Analysis, Raymond S. Avery, Dylan P. Carpenter, Thomas A. Costello Jan 2002

Identifying Safety Strategies For On-Farm Grain Bins Using Risk Analysis, Raymond S. Avery, Dylan P. Carpenter, Thomas A. Costello

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

The potential for grain bin accidents exists each year on Arkansas farms and farms across the nation. The trend toward increasing utilization of on-farm grain drying and storage could lead to an increase in grain bin accidents. The sharp contrast between a safe, efficient operation and one that leads to injury or death can be represented as sets of farmer-decisions and subsequent chance events. A model was constructed to define the risk associated with grain bin entry and in-bin activity so that safety interventions could be identified and implemented to reduce the probability of injury and death. A survey was …

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Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 3 2002, Several Authors Jan 2002

Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 3 2002, Several Authors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

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Juvenile Justice Systems: A Need For Improved Research And Treatment, Tenethrea Thompson, Jean Turner Jan 2002

Juvenile Justice Systems: A Need For Improved Research And Treatment, Tenethrea Thompson, Jean Turner

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

The characteristics of juveniles who commit crimes and a variety of treatment philosophies for juvenile offenders were examined through literature and individual case studies. The literature review and three case studies provided insight into the difficult challenge of providing effective treatment programs for juvenile offenders.

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Instructions For Authors, Discovery Editors Jan 2002

Instructions For Authors, Discovery Editors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

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Expression Patterns Of Novel Wound-Inducible Plant Genes In Medicago Truncatula, Mandy M. Cox, Kenneth L. Korth Jan 2002

Expression Patterns Of Novel Wound-Inducible Plant Genes In Medicago Truncatula, Mandy M. Cox, Kenneth L. Korth

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Terpenoids are an important class of defensive compounds that can accumulate in plants after pathogen infection or injury by chewing insects. Clones encoding putative terpene synthases and an oxidosqualene synthase, isolated from insect-damaged Medicagotruncatula leaves, were selected from an expressed sequence tag (EST) database. The cDNA clones were used as radiolabeled probes to analyze gene expression in leaves treated by known factors that can trigger a defense response in plants. Transcript levels for all of the genes examined increased in response to artificial wounding, insect herbivory, and methyl jasmonate (meJA) treatments, whereas salicylic acid (SA) and glucose oxidase (GOX) had …

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Bradyrhizobium Japonicum And Soybean Symbiotic Response To Glyphosate In Glyphosate-Tolerant Soybeans, Jodie M. Scheele, C. Andy King, Marilynn K. Davies, Larry C. Purcell Jan 2002

Bradyrhizobium Japonicum And Soybean Symbiotic Response To Glyphosate In Glyphosate-Tolerant Soybeans, Jodie M. Scheele, C. Andy King, Marilynn K. Davies, Larry C. Purcell

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Soybean (Glycine max) grain contains approximately 40% protein and 6.5% nitrogen (N) on an elemental basis. Therefore, the plant requires an abundant N supply throughout its life cycle, and symbiotic N fixation of soybean with Bradyrhizobium japonicum provides 40 to 85% of the soybean N. Although soybean cultivars have been genetically engineered to withstand the herbicide glyphosate, B. japonicum grown in culture is sensitive to glyphosate. We hypothesized that glyphosate applied to glyphosate-tolerant soybean would inhibit nodulation by B. japonicum unless B. japonicum could also be selected for glyphosate tolerance. Cultures of B. japonicum were challenged with sublethal doses of …

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86th Annual Meeting, 2002. Program, Academy Editors Jan 2002

86th Annual Meeting, 2002. Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Distribution Of Clinostomum Marginatum (Yellow Grub) Metacercaria In Smallmouth Bass Populations From Crooked Creek In North Central Arkansas, James J. Daly, Bruce Deyoung, Terryl L. Hostetler, Randal J. Keller Jan 2002

Distribution Of Clinostomum Marginatum (Yellow Grub) Metacercaria In Smallmouth Bass Populations From Crooked Creek In North Central Arkansas, James J. Daly, Bruce Deyoung, Terryl L. Hostetler, Randal J. Keller

Journal of the Arkansas Academy of Science

Four hundred thirty-three smallmouth bass (Micropterus dolomieui) were collected from ten sites on Crooked Creek in North Central Arkansas from just below the city of Harrison to the White River in the summers of 1988-90. Necropsy of these hosts for yellow grub (Clinostomum marginatum) metacercariae showed a range of mean abundance (average/fish) from 1.4 ±1.9 (SD) at a far up stream site to 105 ± 368 at the White River juncture. An increasing mean abundance of C. marginatum was seen from the uppermost sites of the creek downstream to the White River. Relating stream mileage with mean abundance gave a …

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Effect Of Tillage And Herbicide Treatments On Redvine (Brunnichia Ovata) Subterranean Morphology, E. C. Gordon, T. C. Keisling, L. R. Oliver, T. A. Castillo Jan 2002

Effect Of Tillage And Herbicide Treatments On Redvine (Brunnichia Ovata) Subterranean Morphology, E. C. Gordon, T. C. Keisling, L. R. Oliver, T. A. Castillo

Journal of the Arkansas Academy of Science

Redvine Brunnichia ovata (Walt.) Shinners is a perennial weed that reproduces from seed, rootstock, and rhizomes. Redvine infested areas that were exposed to different tillage practices, slicing techniques, and herbicide treatments were selected to excavate in order to observe rhizome and root morphology. When comparing tillage systems, deep tillage appeared to delay rhizome development following cultivation, but a characteristic branching occurred over time. Shallow cultivation (2.5 to 7.5m) concentrated rhizomes immediately below the depth of tillage; whereas, no-till areas concentrated rhizomes near the soil surface. Slicing the underground parts of redvine will not kill rhizomes if they are still attached …

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Preparation Of Novel Hydroxyethyl Amine Isosteres As Potential Cathepsin D Inhibitors, Rose M. Mcconnell, Walter E. Godwin, Amy Stefan, Crystal Newton, Nikki Herring, Crissy Goss Jan 2002

Preparation Of Novel Hydroxyethyl Amine Isosteres As Potential Cathepsin D Inhibitors, Rose M. Mcconnell, Walter E. Godwin, Amy Stefan, Crystal Newton, Nikki Herring, Crissy Goss

Journal of the Arkansas Academy of Science

Cathepsin D is a lysosomal aspartic protease found in all mammalian cells and is considered to be one of the main catabolic proteinases. Cathepsin D has been suggested to play a role in the metastatic potential of several types of cancer. A high activated cathepsin D level in breast tumor tissue has been associated with an increased incidence of relapse and metastasis. High levels of active cathepsin D have also been found in colon cancer, prostate cancer, uterine cancer, and ovarian cancer. Hydroxyethyl isosteres with cyclic tertiary amine have proven to be clinically useful as inhibitors of aspartyl proteases similar …

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Fire Effects On Three Trophic Levels In A Central Arkansas Grassland, Laura Skelton, Amy Polk, Brenna C. Fitzgerald, Matthew D. Moran Jan 2002

Fire Effects On Three Trophic Levels In A Central Arkansas Grassland, Laura Skelton, Amy Polk, Brenna C. Fitzgerald, Matthew D. Moran

Journal of the Arkansas Academy of Science

We studied the effect of a late growing-season fire on the plant and foliar arthropod communities in a naturally occurring grassland. In central Arkansas, these grasslands are common on south-facing slopes where shallow soils and hot/dry weather conditions during the summer cannot support the growth of a forest community. Patches of grassland were burned in the autumn (4 November, late growing season), often the time of natural fires in Arkansas, and compared to unburned areas. Fire increased the biomass of forbs and decreased the biomass of grasses, although overall biomass was not different between treatments. Among the foliar arthropods, herbivores …

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Epidermal Papilloma In An Ozark Hellbender (Cryptobranchus Alleganiensis Bishopi) From The Spring River Of Northwest Arkansas, Stanley E. Trauth, John C. Harshbarger, Patrick Daniel Jan 2002

Epidermal Papilloma In An Ozark Hellbender (Cryptobranchus Alleganiensis Bishopi) From The Spring River Of Northwest Arkansas, Stanley E. Trauth, John C. Harshbarger, Patrick Daniel

Journal of the Arkansas Academy of Science

An Ozark hellbender (Cryptobranchus alleganiensis bishopi) with multiple, large, warty skin lesions was collected in the Spring River, Fulton County, Arkansas, in 1994. The specimen was a female, 560 mm in total length, and had a mass of 1,947 g. Tissues were formalin-fixed, and three lesions were processed for histopathology. The normal skin at the tumor margins had a stratified squamous epidermis overlying a loose, well-vascularized, heavily pigmented dermis. Poison glands and mucous glands extended from the epidermis into the dermis. The lesions, in contrast, were masses of epidermal cells up to 100 times thicker than the normal epidermis. They …

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Bats Of The Jessieville Ranger District, Ouachita National Forest, Arkansas, C. Renn Tumlison, Tobin Fulmer, Tommy Finley, David A. Saugey Jan 2002

Bats Of The Jessieville Ranger District, Ouachita National Forest, Arkansas, C. Renn Tumlison, Tobin Fulmer, Tommy Finley, David A. Saugey

Journal of the Arkansas Academy of Science

During July and August 2000 and 2001, mist nets were set concentrated on three drainages in the Jessieville District of the Ouachita National Forest: North Fork Ouachita River (ten sites), Irons Fork Creek (five sites), and Muddy Creek (two sites). A total of 83 bats representing seven species was caught during 20 evenings (43 net nights). Sampled habitats included pools in road ruts, intermittent streams, man-made ponds on ridgelines, a wet road rut fed by a seep, small drainages that flowed only after a heavy rain, a standing pool in a clearing, and larger streams. Eastern red bats (Lasiurus borealis) …

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Hazards Of Fishing Gear To Wildlife Of Lakes In Arkansas, Tobin Fulmer, C. Renn Tumlison Jan 2002

Hazards Of Fishing Gear To Wildlife Of Lakes In Arkansas, Tobin Fulmer, C. Renn Tumlison

Journal of the Arkansas Academy of Science

No abstract provided.

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Habitat And Abundance Of The Ouachita Darter (Percina Sp. Nov.), Charles J. Gagen, Kendall R. Moles, Lisa J. Hlass, Richard W. Standage Jan 2002

Habitat And Abundance Of The Ouachita Darter (Percina Sp. Nov.), Charles J. Gagen, Kendall R. Moles, Lisa J. Hlass, Richard W. Standage

Journal of the Arkansas Academy of Science

No abstract provided.

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Coccidian Parasites (Apicomplexa: Eimeriidae) Of Select Rodents Of Western And Southwestern Arkansas And Northeastern Texas, Chris T. Mcallister, Joshua E. Kessler Jan 2002

Coccidian Parasites (Apicomplexa: Eimeriidae) Of Select Rodents Of Western And Southwestern Arkansas And Northeastern Texas, Chris T. Mcallister, Joshua E. Kessler

Journal of the Arkansas Academy of Science

No abstract provided.

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