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Full-Text Articles in Life Sciences

Instructions For Authors, Discovery Editors Jan 2001

Instructions For Authors, Discovery Editors

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

No abstract provided.


Evaluation Of Chilling Requirements For Six Arkansas Blackberry Cultivars Utilizing Stem Cuttings, Dayanee Yazzetti, John R. Clark Jan 2001

Evaluation Of Chilling Requirements For Six Arkansas Blackberry Cultivars Utilizing Stem Cuttings, Dayanee Yazzetti, John R. Clark

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

Woody perennial plants including blackberries (Rubus subgenus Rubus) require certain amounts of chilling or rest hours below 7ºC during the dormant season for successful bud break the following year. Arkansas-developed blackberry cultivars are being grown in various climates worldwide and all cultivars need chilling requirement estimates for accurate recommendations of adaptation. Determining chilling requirement using stem cuttings collected from field-grown plants rather than whole plants is a desirable system. We conducted a study to evaluate both artificial and field chilling of six cultivars. For the artificial-chilling study, 12- node stem cuttings were collected 2 days after the first killing frost. …


Sulfur Amino Acid Requirements Of Broilers From Two To Five Weeks Of Age, Jill A. Townsend, H. R. (Trey) Pope, Jason L. Emmert Jan 2001

Sulfur Amino Acid Requirements Of Broilers From Two To Five Weeks Of Age, Jill A. Townsend, H. R. (Trey) Pope, Jason L. Emmert

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

Phase-feeding (PF) in broiler chickens has been researched as a way to reduce feed costs without reducing growth performance and yield. Predicted amino acid requirements for PF are generated using linear regression equations derived from best estimates of lysine (Lys), sulfur amino acid (SAA), and threonine (Thr) requirements. During the late starter and early grower periods, predicted requirements for the SAA methionine (Met) and cysteine (Cys) are higher than levels recommended by the National Research Council (NRC), and previous research suggests that SAA may be lowered during the grower period without sacrificing growth performance or yield. The objective of this …


Development Of The Interactive Broiler Income Spreadsheet, Tara Shofner, H. L. Goodwin Jr. Jan 2001

Development Of The Interactive Broiler Income Spreadsheet, Tara Shofner, H. L. Goodwin Jr.

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

The poultry industry has experienced unprecedented increased efficiencies since 1960 in large part due to vertical integration facilitated by production contracts between growers and integrators. As growers seek information about contract production they need to be well informed about all aspects of the process, especially potential income. Recent poultry grower complaints have surfaced as a result of incorrect expense and revenue expectations. The Interactive Broiler Income Spreadsheet (IBIS) is being developed to enable current and prospective poultry producers to better estimate income. IBIS, an unbiased Excel™ spreadsheet tool to assist in decision making regarding broiler production profitability, uses actual grower …


Vasotocin Receptor Expression In The Brain And Pituitary Gland During The Ovulatory Cycle Of The Fowl, Kelly Shaffer, Jorge A. Vizcarra, John Kirby Jan 2001

Vasotocin Receptor Expression In The Brain And Pituitary Gland During The Ovulatory Cycle Of The Fowl, Kelly Shaffer, Jorge A. Vizcarra, John Kirby

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

Vasotocin receptors are members of seven transmembrane spanning G-protein associated receptors. Several isoforms have been recognized in mammals and birds. It has been shown that VT-1 expression occurs primarily in the brain while VT-2 expression occurs mainly in the pituitary. There is no current evidence to support that both VTR-1 and -2 are found in a single tissue. Our goal in this experiment was to see if VT-1 and VT-2 receptor mRNA expression varied in known sites of expression over the period of the ovulatory cycle of broiler breeder hens. In order to study potential changes in VT-1 and VT-2 …


Correlating Fissure Occurrence To Rice Quality For Various Drying And Tempering Treatments, Monica J. Jimenez, Terry J. Siebenmorgen, A. G. Cnossen Jan 2001

Correlating Fissure Occurrence To Rice Quality For Various Drying And Tempering Treatments, Monica J. Jimenez, Terry J. Siebenmorgen, A. G. Cnossen

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

When a rice kernel fissures, it can break in subsequent food processing operations and lose its commercial value. Head rice yield (HRY) is a measure of the percent of kernels that remain whole (at least three-fourths of original length) after rice has been milled. Our experiment was designed to test the effect of a rapid state transition during drying and tempering processes using cultivars Bengal and Cypress. ‘Bengal’ is a medium-size kernel and ‘Cypress’ is a longsize, thinner grained cultivar. Immediately after drying, the rice samples were separated into four sub-samples and tempered for 0, 80, 160, or 240 minutes …


Prediction Of Rice Texture From Starch Profiles Measured Using High-Performance Liquid Chromatography, Hazel Fromm, J. F. Meullenet Jan 2001

Prediction Of Rice Texture From Starch Profiles Measured Using High-Performance Liquid Chromatography, Hazel Fromm, J. F. Meullenet

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

Starch determines a large proportion of the textural properties of cooked rice. The amylose: amylopectin ratio plays a significant role in the functionality of native starch. In this study a medium-grain rice cultivar, ‘Bengal’, was used for starch structure characterization using high performance size-exclusion chromatography (HPSEC). This cultivar is characterized by having lower amylose content (15% to 20%) than long grain cultivars and being sticky when cooked, similar to short-grain cultivars. Rice samples were harvested in 1999 from five locations around Arkansas at state verification trials where cultural practices are closely monitored. Samples of this cultivar stored at a specified …


Peripheral Blood Leukocyte Response And Macrophage Function During Eimeria Adenoeides Infection In Turkey Poults, Amanda D. Drake, Sarah E. Heuer, Timothy G. Kimball, Timothy O. Peters, H. David Chapman, Gisela F. Erf Jan 2001

Peripheral Blood Leukocyte Response And Macrophage Function During Eimeria Adenoeides Infection In Turkey Poults, Amanda D. Drake, Sarah E. Heuer, Timothy G. Kimball, Timothy O. Peters, H. David Chapman, Gisela F. Erf

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

Intestinal coccidiosis, caused by various species of Eimeria, is an economically important disease of chickens and turkeys. The peripheral blood leukocyte response and macrophage functions during a coccidial infection in turkeys have not been defined. To examine these aspects of innate immunity during primary Eimeria infection in turkeys, 4-week-old poults were orally inoculated with either 50,000 E. adenoeides oocyst (24 infected poults) or water (24 control poults). To monitor the concentrations and proportions of white blood cells (WBC) throughout the course of infection, heparinized blood was collected from 12 infected and 12 control poults prior to inoculation (day 0), and …


Improvements In Turfgrass Color And Density Resulting From Comprehensive Soil Diagnostics, Matt Cordell, Jonathan Davis, David E. Longer Jan 2001

Improvements In Turfgrass Color And Density Resulting From Comprehensive Soil Diagnostics, Matt Cordell, Jonathan Davis, David E. Longer

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

There are roughly 220 golf courses in Arkansas, and as many as 50% of these courses were constructed using common bermudagrass fairways. Although resilient, common bermudagrass loses density and quality over time. In this experiment physical and chemical properties of the soil were analyzed to determine the causes of decline in turf quality observed on several fairways of a local golf course. Once a particular fairway was selected for study and preliminary soil sampling conducted, GS+, a geostatistical computer program, was used to map the location of certain chemical deficiencies. A moderate to severe Mg deficiency was detected throughout the …


The Possible Enzymatic Differences Between Cattle And Sheep In Their Response To Ergot Alkaloids, Susan M. Cannon, Charles F. Rosenkrans, Ali Moubarak Jan 2001

The Possible Enzymatic Differences Between Cattle And Sheep In Their Response To Ergot Alkaloids, Susan M. Cannon, Charles F. Rosenkrans, Ali Moubarak

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

Ergotamine is an ergot alkaloid associated with fescue toxicosis of livestock who have grazed endophyte-infected fescue. High performance liquid chromatography (HPLC) was used to detect individual or species-specific differences in the metabolism of ergotamine by liver cytochrome P450 of sheep and cattle. Livers were collected from four steers and two sheep. The diet of the steers used in this study consisted of two being fed a grain diet, one steer grazing endophyte-infected fescue, and the final steer grazing endophyte-free fescue. The two lambs were both fed a grain diet. Livers were prepared and examined for the disappearance of ergotamine and …


Letter From The Dean, Gregory J. Weidemann Jan 2001

Letter From The Dean, Gregory J. Weidemann

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

No abstract provided.


Contents, Discovery Editors Jan 2001

Contents, Discovery Editors

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

No abstract provided.


Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 2 2001, Several Authors Jan 2001

Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 2 2001, Several Authors

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

No abstract provided.


Arkansas Field Botany (Flora And Vegetation) Bibliography (1988-2000), James H. Peck, C. Theo Witsell, Thomas L. Foti Jan 2001

Arkansas Field Botany (Flora And Vegetation) Bibliography (1988-2000), James H. Peck, C. Theo Witsell, Thomas L. Foti

Journal of the Arkansas Academy of Science

The floristic richness and diversity of vegetation in Arkansas continues to require and stimulate a growing body of taxonomic and ecological research publications. Peck and Peck (1988) listed 766 references, including those of the two prior lists. Since then we have gathered 417 additional references. The total list now contains 1,183 references, with 70% prepared or published since 1970. This update is provided for four reasons: 1) to compile a comprehensive source to direct and facilitate future studies, 2) to provide easier access to many reports not normally located in electronic databases, 3) to improve communications with botanists outside Arkansas, …


Food Habits Of The Ouachita Dusky Salamander, Desmognathus Brimleyorum (Caudata: Plethodontidae), In Arkansas, David H. Jamieson, Peter J. Rust, Stanley E. Trauth Jan 2001

Food Habits Of The Ouachita Dusky Salamander, Desmognathus Brimleyorum (Caudata: Plethodontidae), In Arkansas, David H. Jamieson, Peter J. Rust, Stanley E. Trauth

Journal of the Arkansas Academy of Science

No abstract provided.


Diversity Of Lamium (Lamiceae) In Arkansas, Including Occurrences Of Lamium Hybridum And Flower Color Forms, Jason A. Haley, Daniel L. Marsh Jan 2001

Diversity Of Lamium (Lamiceae) In Arkansas, Including Occurrences Of Lamium Hybridum And Flower Color Forms, Jason A. Haley, Daniel L. Marsh

Journal of the Arkansas Academy of Science

No abstract provided.


Status Of Pet Mountain Lions (Puma Concolor) In Arkansas, D. Blake Sasse Jan 2001

Status Of Pet Mountain Lions (Puma Concolor) In Arkansas, D. Blake Sasse

Journal of the Arkansas Academy of Science

No abstract provided.


Redescription Of Eimeria Macyi (Apicomplexa: Eimeriidae) From The Eastern Pipistrelle, Pipistrellus Subflavus (Mammalia: Chiroptera), From Arkansas, Chris T. Mcallister, Steve J. Upton, Stanley E. Trauth, David W. Allard Jan 2001

Redescription Of Eimeria Macyi (Apicomplexa: Eimeriidae) From The Eastern Pipistrelle, Pipistrellus Subflavus (Mammalia: Chiroptera), From Arkansas, Chris T. Mcallister, Steve J. Upton, Stanley E. Trauth, David W. Allard

Journal of the Arkansas Academy of Science

No abstract provided.


Hydrophobic Matching Of Short Gramicidins With Phospholipids, Elizabeth Dunn Jan 2001

Hydrophobic Matching Of Short Gramicidins With Phospholipids, Elizabeth Dunn

Inquiry: The University of Arkansas Undergraduate Research Journal

Given the highly stochastic nature of larval supply, coral reef fish may often settle in sub-optimal habitats with limited prey. This study examines the foraging and territorial habits of a coral feeding butterflyfish, Chaetodon baronessa, living in two contrasting habitats with markedly different coral prey. In exposed front reef habitats, where coral prey was highly abundant, C. baronessa was highly selective in its choice of prey and aggressively maintained small territories. In contrast, in back reef habitats where coral prey was scarcer, C. baronessa was more generalist in its choice of prey, and had larger territories that were only weakly …


Evaluation Of Chilling Requirements For Six Arkansas Blackberry Cultivars Utilizing Stem Cuttings, Dayanee Yazzetti Jan 2001

Evaluation Of Chilling Requirements For Six Arkansas Blackberry Cultivars Utilizing Stem Cuttings, Dayanee Yazzetti

Inquiry: The University of Arkansas Undergraduate Research Journal

Woody perennial plants including blackberries (Rubus subgenus Rubus Watson) require certain amounts of chilling or rest hours below 7T during the dormant season for successful bud break the following year. Blackberry cultivars developed in Arkansas are being grown in various climates worldwide, and all cultivars need chilling requirement estimates for accurate recommendations of adaptation. Determining chilling requirements using stem cuttings collected from field-grown plants rather than whole plants is a desirable system. We conducted a study to evaluate both artificial- and field-chilling of six cultivars. For the artificial-chilling study, 12-node stem cuttings were collected 2 days after the first killing …


Voltage Gating Of A Model Membrane Spanning Channel, Eric Miller Jan 2001

Voltage Gating Of A Model Membrane Spanning Channel, Eric Miller

Inquiry: The University of Arkansas Undergraduate Research Journal

Channels in cell membranes are important for intercellular communication and especially for the function of the nervous system in higher vertebrates. These channels consist of proteins made from the 20 common amino acids. Channel proteins are embedded into the lipid bilayer membranes of living cells and function by allowing the specific passage of a positively charged material such as sodium or potassium ions across the membrane in response to an external signal. The external signaloeither a chemical signal or a voltageoregulates the opening and closing of channels. In an attempt to understand the voltage-dependent opening of channels (igatingi), we are …


Diet And Territory Size Of Butterflyfish In Habitats With Varying Coral Cover And Composition, Michael Berumen Jan 2001

Diet And Territory Size Of Butterflyfish In Habitats With Varying Coral Cover And Composition, Michael Berumen

Inquiry: The University of Arkansas Undergraduate Research Journal

Given the highly stochastic nature of larval supply, coral reef fish may often settle in sub-optimal habitats with limited prey. This study examines the foraging and territorial habits of a coral feeding butterflyfish, Chaetodon baronessa, living in two contrasting habitats with markedly different coral prey. In exposed front reef habitats, where coral prey was highly abundant, C. baronessa was highly selective in its choice of prey and aggressively maintained small territories. In contrast, in back reef habitats where coral prey was scarcer, C. baronessa was more generalist in its choice of prey, and had larger territories that were only weakly …


Molecular Orbital Studies Of Nitrosyl Metalloporphyrin Complexes, John P. Graham, Genevive Brown Jan 2001

Molecular Orbital Studies Of Nitrosyl Metalloporphyrin Complexes, John P. Graham, Genevive Brown

Journal of the Arkansas Academy of Science

Molecular orbital calculations are applied to the study of the structure and bonding of nitrosyl metalloporphyrin complexes. The Fenske-Hall approximate molecular orbital method and the Amsterdam Density Functional (ADF) method are used. The calculations provide qualitative and quantitative explanations for the observed structural differences between the nitrosyl porphyrin complexes ofiron, manganese, and cobalt. It is proposed that the energy of the highest occupied molecular orbital (HOMO) of these complexes is primarily responsible for the observed structural differences. The interaction between the nitrosyl ligand and metal dz2 orbital results in an antibonding orbital that is occupied in the complexes of Fe …


Distribution And Status Of Ophiogomphus Westfalli (Ondonata: Gomphidae) In Missouri And Arkansas, George L. Harp, Linden Trial Jan 2001

Distribution And Status Of Ophiogomphus Westfalli (Ondonata: Gomphidae) In Missouri And Arkansas, George L. Harp, Linden Trial

Journal of the Arkansas Academy of Science

Ophiogomphus westfalli is endemic to the Interior Highlands (Ozark Plateaus and Ouachita Mountains), in Missouri, Arkansas and southeastern Kansas. First described in 1985, its life history is still little known. Prior to 1997, this species was known from only six sites in Missouri and 10 in Arkansas. From late May through late July in both 1999 and 2000 we surveyed 49 sites, three of them twice each, on Missouri Ozark streams inorder to further clarify the distribution and relative abundance of this dragonfly. Adults, nymphs and/or exuviae were found at 23 sites. Literature and museum searches bring to 72 locations …


Identification Of Florida Largemouth Bass Alleles In Arkansas Public And Private Aquaculture Ponds, Ronald L. Johnson, Randall Staley Jan 2001

Identification Of Florida Largemouth Bass Alleles In Arkansas Public And Private Aquaculture Ponds, Ronald L. Johnson, Randall Staley

Journal of the Arkansas Academy of Science

The Florida subspecies of the largemouth bass (LMB) has often been introduced into waters outside of its range, with escape of individuals into associated waterways common. Sustaining pure lines within controlled hatchery settings is also difficult. The present study investigated LMB populations by way of allozyme analysis of three diagnostic loci of 115 LMB in three public and seven private aquaculture ponds within Arkansas. The goal was to determine the success of hatcheries in maintaining pure subspecies. None of the pond populations studied were fixed for all alleles. Private ponds had northern LMB allele frequencies of up to 0.40 in …


Perceived Damage By Elk In The Arkansas Ozarks, Jennifer H. Herner-Thogmartin, Kimberly G. Smith, Michael E. Cartwright Jan 2001

Perceived Damage By Elk In The Arkansas Ozarks, Jennifer H. Herner-Thogmartin, Kimberly G. Smith, Michael E. Cartwright

Journal of the Arkansas Academy of Science

Wildlife managers in Arkansas are faced with managing a growing population of Rocky Mountain elk (Cervus elaphus neloni) that has extended its range to incorporate private lands near the Buffalo National River (BNR) in northcentral Arkansas. This range expansion has created conflicts between private landowners and wildlife management personnel. To document the extent of damage and assess attitudes of landowners with elk on their land, interviews were conducted with landowners who contacted us or the Arkansas Game and Fish Commission about problems with elk. A survey also was created and sent to landowners who live near the BNR in Boone …


Survey Of The Macrobenthic Community In Ferguson Lake, Saline County, Arkansas, John D. Rickett, E. P. (Perk) Floyd Jan 2001

Survey Of The Macrobenthic Community In Ferguson Lake, Saline County, Arkansas, John D. Rickett, E. P. (Perk) Floyd

Journal of the Arkansas Academy of Science

One hundred thirty benthic samples were collected on 33 visits to Ferguson Lake, Saline County, Arkansas, between May 1997 and October 2000. Sediments were visually examined and described, and some were returned to the lab for sediment oxygen demand (SOD) analysis. Fourteen taxa, representing five phyla of invertebrates, were identified. In all samples, oligochaetes, chaoborids, and chironomids comprised the majority of individuals, reaching densities up to 7449, 14,208, and 8783 per m2, respectively. When seasonally grouped, largest total abundances and greatest abundances of most taxa were collected during the winter months (December-February). A minor abundance peak occurred in July due …


Characterization Of A PorosTm-Fumonisin B1 Affinity Column For Isolating Ceramide Synthase From Rat Liver, S. Jernigan, W. B. Melchior Jr., G. R. Jenkins, K. L. Rowland, D. W. Roberts, P. C. Howard, H. Tolleson Jan 2001

Characterization Of A PorosTm-Fumonisin B1 Affinity Column For Isolating Ceramide Synthase From Rat Liver, S. Jernigan, W. B. Melchior Jr., G. R. Jenkins, K. L. Rowland, D. W. Roberts, P. C. Howard, H. Tolleson

Journal of the Arkansas Academy of Science

Fumonisin B1 is a mycotoxin produced by fungi of the genus Fusarium, common pathogens of corn and other grain plants. Toxic effects associated with fumonisin B1 include equine leukoencephalomacia, porcine pulmonary edema, rat renal carcinoma, and murine hepatocellular carcinoma. Increased risk for esophageal cancer in humans has been epidemiologically associated with consumption of corn contaminated with Fusarium, suggesting that fumonisin B1 may be involved. The biological effects of fumonisin B1 exposure result primarily from disruption of de novo sphingolipid biosynthesis via inhibition of ceramide synthase. Exposure of animals or cultured cells to fumonisin B1 results in the characteristic accumulation of …


New Records Of The Woodchuck (Marmota Monax) From Southern Arkansas, C. Renn Tumlison, Anna Smith, Randy Frazier Jan 2001

New Records Of The Woodchuck (Marmota Monax) From Southern Arkansas, C. Renn Tumlison, Anna Smith, Randy Frazier

Journal of the Arkansas Academy of Science

No abstract provided.


Distribution Of Leconte's Free-Tailed Bat (Tadarida Brasiliensis Cynocephala) In Arkansas, With Notes On Reproduction And Natural History, David A. Saugey, D. Blake Sasse, J. D. Wilhide, Drew Reed, Tammy R. Jones, Darrell R. Heath, Daniel R. England Jan 2001

Distribution Of Leconte's Free-Tailed Bat (Tadarida Brasiliensis Cynocephala) In Arkansas, With Notes On Reproduction And Natural History, David A. Saugey, D. Blake Sasse, J. D. Wilhide, Drew Reed, Tammy R. Jones, Darrell R. Heath, Daniel R. England

Journal of the Arkansas Academy of Science

During the past 20 years (1982-2001) we have studied the biology, occurrence and distribution of LeConte's (Brazilian) free-tailed bat, Tadarida brasiliensis cynocephala, in Arkansas. Colonies and individuals were reported from man made structures only. Four new county records have been documented since 1988, extending the range from the central part of the state to Arkansas's northern-most tier of counties. Numerous nuisance maternity colonies were investigated during exclusion activities and one, year-round colony provided the majority of reproductive data. A total of 152 free-tailed bats was submitted to the Arkansas Department of Health Rabies Laboratory (1982-2001); most during February through April, …