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

Digital Commons Network

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

Articles 1 - 14 of 14

Full-Text Articles in Entire DC Network

Letter From The Dean, Gregory J. Weidemann Jan 2002

Letter From The Dean, Gregory J. Weidemann

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

No abstract provided.


Land-Use Effects On Soil-Water Retention Characteristic, Naomi Colton, Kristofor Brye Jan 2002

Land-Use Effects On Soil-Water Retention Characteristic, Naomi Colton, Kristofor Brye

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

Tillage can negatively affect soil physical properties such as bulk density, organic matter content, and soil hydraulic properties, which in turn affect how plants grow. The objective of this study was to evaluate water retention characteristics of a Jay silt loam soil under cultivated agriculture and native tallgrass prairie in northwest Arkansas. Air-dry soil samples collected from 0-10 cm depth were re-wet with varying amounts of distilled water to create a range of water contents. After overnight equilibration, the water potential was measured on the re-wet soil samples using a dewpoint potentiameter. The relationship between water potential (Ψ) and water …


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.


Contents, Discovery Editors Jan 2002

Contents, Discovery Editors

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

No abstract provided.


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, …


Preliminary Results From A Survey On The Prevalence Of Parasitic Helminths And Protozoa In Raccoons, Opossums, And Skunks, Michelle Belviy, T. A. Yazwinski, C. A. Tucker, Jennifer Robins Jan 2002

Preliminary Results From A Survey On The Prevalence Of Parasitic Helminths And Protozoa In Raccoons, Opossums, And Skunks, Michelle Belviy, T. A. Yazwinski, C. A. Tucker, Jennifer Robins

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

Raccoons, skunks, and opossums (N=57, 60, and 60, respectively) were necropsied for parasite detection and identification from September, 2001 until April, 2002. Qualitative coprological exams and adult Baylisascaris collections have been completed. Fecal stages and/or types found were Baylisascaris and Strongyloides-type (skunks and raccoons); Capillaria and Trichostrongyletype (raccoons and opossums); Acanthacephalan and ascarid type (opossums only); free larvae (skunks only); and coccidial (protozoan) oocysts (all three host species). Adult Baylisascaris were recovered from 33.3% of the raccoons and 58.3% of the skunks. Data collection relative to this survey, which is still ongoing, includes the determination of Sarcocystis prevalence in excised …


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 …


Quantification Of Land-Use Impact On Stream Water Quality, Scott Dennis, Indrajeet Chaubey, Brian Haggard Jan 2002

Quantification Of Land-Use Impact On Stream Water Quality, Scott Dennis, Indrajeet Chaubey, Brian Haggard

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

Accelerated eutrophication of Beaver Lake in northwest Arkansas is a major environmental concern. When developing watershed-management plans to protect lake water quality, it is important that linkages among land-use activities and water quality of tributary streams be quantified. This study assessed longitudinal base-flow and storm-flow water quality at War Eagle Creek and quantified linkages between stream water quality and land-use conditions within the War Eagle Creek sub-watershed of the Beaver Lake watershed. We collected six water samples: three from base-flow conditions and three from storm-flow conditions during Spring 2002. In general, concentrations of nitrate nitrogen (NO3-N), total N (TN), total …


Organophosphate Toxicosis In Chickens: A Case Report, Robert Hubbard, Judith England, E. Dustan Clark Jan 2002

Organophosphate Toxicosis In Chickens: A Case Report, Robert Hubbard, Judith England, E. Dustan Clark

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

Two cases of organophosphate toxicity were diagnosed at the University of Arkansas Poultry Science Department poultry research farm in the Spring of 2002. In both cases the birds were being treated with the organophosphate RaVap® for Northern Fowl Mites (Ornithonyssus sylvarium) infestations. A total of 61 birds died and 13 were treated successfully with atropine sulphate.


The Influence Of Storing High Moisture-Content Rough Rice On Milling Quality, Julita M. Manski, Terry Siebenmorgen Jan 2002

The Influence Of Storing High Moisture-Content Rough Rice On Milling Quality, Julita M. Manski, Terry Siebenmorgen

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

The objective of this research was to determine the influence on drying characteristics of storing high-moisture content (MC) rough rice under various conditions and durations before drying. Two cultivars of rice, 'Bengal', a medium-grain cultivar, and 'Cypress', a long-grain cultivar, were used. The MC of 'Bengal' was 24.8%1 and that of 'Cypress' was 20.4% at harvest. Immediately after harvest, drying runs were performed with samples of both cultivars under two drying air conditions: one at 51.7°C (125°F) and 25% relative humidity (RH), and the other at 60°C (140°F) and 17% RH. Storage treatments using the high MC rice were also …


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 …


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.


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 inbin activity so that safety interventions could be identified and implemented to reduce the probability of injury and death. A survey was …


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.