Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 18 of 18
Full-Text Articles in Life Sciences
Isolation And Characterization Of Temperature-Sensitive Protein Synthesis Mutants Of Escherichia Coli By Directed Mutagenesis Of The Defective Bacteriophage Lambda Fus2, Kenton L. Lohman
Electronic Theses and Dissertations
Mutagenesis of the defective transducing bacteriophage lambda fus2 was used to isolate a collection of temperature-sensitive mutants of E. coli in the major ribosomal protein gene cluster. Four mutants were examined in detail. Two of the mutants were resistant to the ribosomal antibiotics neamine and spectinomycin. Another mutant was defective in 50S ribosomal subunit assembly at 42(DEGREES)C. The 30S subunit proteins S17 and S19 were changed in two different mutants. Each protein migrated as a more basic species in two-dimensional gels of ribosomal proteins. Ribosomes from each of the four mutants examined showed a temperature-dependent reduction in translational activity in …
Cisplatin Ototoxicity In The Guinea Pig: An Electrophysiological, Morphological, And Biochemical Study, Sarah E. Barron
Cisplatin Ototoxicity In The Guinea Pig: An Electrophysiological, Morphological, And Biochemical Study, Sarah E. Barron
Electronic Theses and Dissertations
The purpose of this study was to determine changes induced by cisplatin on hair cell (HC) morphology, compound action potential (CAP), Preyer reflex (PR), and Na,K-ATPase activity in the cochlear lateral wall. Guinea pigs were treated with either 0.42, 0.83, 1.17, 1.50 mg/kg cisplatin, i.p. or sterile water for 12 consecutive days and tested on day 13. HC condition was visualized with scanning electron microscopy (SEM), CAP was initiated with a 1 volt click, and Na,K-ATPase activity was measured by the method of Fiske and SubbaRow. HC damage was linear with dose and occurred throughout the turns of the cochlea …
Failure Of Opioids To Modify Noradrenergic Neuronal Recovery From A Dorsal Bundle Lesion In Neonatal Rats, Ellen L. Kunkel-Bagden
Failure Of Opioids To Modify Noradrenergic Neuronal Recovery From A Dorsal Bundle Lesion In Neonatal Rats, Ellen L. Kunkel-Bagden
Electronic Theses and Dissertations
Morphine and exogenous opioid peptides alter the development of central noradrenergic neurons damaged by neonatal treatment with the neurotoxin 6-hydroxydopa. Transection of the dorsal noradrenergic bundle (DNB) in neonatal rats produces nearly the same alteration in the developmental pattern. It was of interest to determine whether morphine or an exogenous opioid peptide (metenkephalin) was able to modify the recovery of noradrenergic neurons after neonatal surgical transection of the DNB. Neonatal rats were divided into two groups. Both groups received saline (0.85%) or naloxone (2.0 mg/kg) by the intraperitoneal (i.p.) route. In the first group the animals received an additional i.p. …
Two Year Survival And Growth Of Loblolly Pine Seedlings From Two Texas Seed Sources On Lignite Minesoils, Gerald Allen Wood
Two Year Survival And Growth Of Loblolly Pine Seedlings From Two Texas Seed Sources On Lignite Minesoils, Gerald Allen Wood
Electronic Theses and Dissertations
Loblolly pine seedlings from Lost Pines (drought-hardy) and East Texas (regular) seed sources were planted in lignite minesoils in Panola County, Texas. Heights, root-collar diameters, and survival were monitored for two years. Treatments included application of Pisolithus tinctorius basidiospores immediately after planting and use of acephate for tip moth control during the second growing season. Standard foliar analyses were conducted at the end of the second growing season. East Texas seedlings grew more in height and root-collar diameter, and had higher survival percentages than Lost Pines. No growth response from treatment with P. tinctorius was observed. Treatment with acephate resulted …
Sulfate Leaching From Sulphur Binding Agents In Experimental Asphalt Pavement, Angelina County, Texas, Peter Blanchette
Sulfate Leaching From Sulphur Binding Agents In Experimental Asphalt Pavement, Angelina County, Texas, Peter Blanchette
Electronic Theses and Dissertations
Sulfate leaching from sulphur-binding agents used in asphalt pavement was significantly higher (p>.05) from four layers of a mixture of a single aggregate base material of hot sand, when compared to all other treatments. Analysis of the data showed that the other treatments had no overall effect on the soil sulfates. Four layers of a single aggregate of hot sand increased the quantity of sulfates in the soil by 107%. I recommend the use of sulphur-asphalt binder with the type "D" base material throughout construction or when two layers of the type "D" base material are placed on top …
Human Lung Tryptase Purification And Characterization, Timothy J. Smith
Human Lung Tryptase Purification And Characterization, Timothy J. Smith
Electronic Theses and Dissertations
Human lung tryptase (HLT), a mast cell derived trypsin-like enzyme, was isolated from whole human lung tissue obtained at autopsy. Increased yields from this purification process allowed extensive characterization of the enzyme. One of the critical steps in the purification scheme was the use of a linear heparin gradient to elute active material from cellulose phosphate. Gel filtration studies in 1.0 M NaCl yielded an apparent M(,r) of 135,000, and subsequent electrophoresis on sodium dodecyl sulfate-polyacrylamide gels demonstrated the presence of two active species with apparent M(,r) = 30,900 and 31,600. Enzymatic activity was sensitive to NaCl concentrations above 0.05 …
Comparison Of Two Phosphorus Tests On Calcareous Soils Of Eastern South Dakota, Mohamed Ali
Comparison Of Two Phosphorus Tests On Calcareous Soils Of Eastern South Dakota, Mohamed Ali
Electronic Theses and Dissertations
Phosphorus is an important nutrient in crop production, since many soils in their native state do not contain sufficient available phosphorus to maximize crop yield. Now, more than ever, the importance of an adequate supply of plant nutrients to insure [sic] sufficient crop production is being recognized. Soil scientists and agronomists are continually striving to overcome nutrient deficiencies as well as use improved management practices in order that yields may more nearly approach the genetic limit of crop plants. Phosphorous forms sparingly soluble compounds with divalent and trivalent cations in soils. Therefore, the amount of P in the soil solution …
Studies On Perennial Weed Control In South Dakota, Steven Robert Gylling
Studies On Perennial Weed Control In South Dakota, Steven Robert Gylling
Electronic Theses and Dissertations
Studies were conducted to measure efficacy and economics of selected herbicide treatments for leafy spurge control in pasture, and to characterize the interaction of ammonium sulfate and glyphosate for quackgrass control. Several treatments resulted in leafy spurge control exceeding 90% in the tested pasture. Mean herbage dry-weight yield in treated plots was 2340 kg/ha, a 67% increase over untreated plots. Forage yields did not significantly differ among treatments controlling 90% or more leafy spurge. Marginal net return over marginal cost from herbicide treatments ranged from $35 to loss of $63/ha. Treatments providing satisfactory leafy spurge control with minimum economic risk …
Response Of Five Spring Wheat Cultivars To Drought, Gregory Keith Hess
Response Of Five Spring Wheat Cultivars To Drought, Gregory Keith Hess
Electronic Theses and Dissertations
Response of plants to water stress are numerous and interrelated. Morphological traits and growth patterns have been studied and reviewed extensively. Root growth patterns, leaf area and thickness, presence of cuticle hair and waxes, leaf movement, and wilting are only a few traits studied. Metabolic functions and how water stress affects these processes through stomatal behavior, transpiration rates and carbon dioxide exchange rates have also been reviewed. Plant breeders are continually searching for traits which aid in selecting for high yielding genotypes in any one environment. Moisture is often limiting in South Dakota's environment, leading to relatively low grain yields …
The Effects Of Nitrogen And Tillage On Denitrification Rates And The Yield Of Corn, Oats, And Soybeans In Eastern South Dakota, Brian Robert Hilton
The Effects Of Nitrogen And Tillage On Denitrification Rates And The Yield Of Corn, Oats, And Soybeans In Eastern South Dakota, Brian Robert Hilton
Electronic Theses and Dissertations
Two field experiments were established in 1983 to evaluate the effect of nitrogen (N) on corn, oats and soybeans grown under various tillage sytems [sic] in east central South Dakota. A corn-oats rotation was grown under moldboard plow (MP), chisel plow (CH), and no-till (NT) tillage systems in a Poinsett silty clay loam soil (Udic Haplaboroll, fine-silty, mixed). In southeast South Dakota a corn-soybean rotation and a continous [sic] corn rotation were grown under MP NT and till plant (TP) and MP CH and NT systems, respectively on an Egan silty clay loam soil (Udic Haplustoll fine silty mixed). Nitrogen …
An Ecological Study Of The Vegetation Of The Grand River/Cedar River, Sioux, And Ashland Districts Of The Custer National Forest, Paul Luther Hansen
An Ecological Study Of The Vegetation Of The Grand River/Cedar River, Sioux, And Ashland Districts Of The Custer National Forest, Paul Luther Hansen
Electronic Theses and Dissertations
A land-classification system based on potential natural vegetation is presented for the Grand River/Cedar River, Sioux, and Ashland Districts of the Custer National Forest. The districts are located in northwestern South Dakota, southwestern North Dakota, and southeastern Montana. The vegetation was characterized according to habitat type based on concepts and methods developed by Daubenmire. A total of 169 stands were intensively sampled over a four-year period. Twenty-six habitat types were described including eight steppe, nine shrub-steppe, four woodland, and five forested habitat types. In addition, two shrub-steppe community types were identified. A diagnostic key is provided for field identification of …
Evaluation Of Yield And Quality Of Cheddar Cheese Manufactured From Milk With Added Whey Protein Concentrate, Kirk Alan Baldwin
Evaluation Of Yield And Quality Of Cheddar Cheese Manufactured From Milk With Added Whey Protein Concentrate, Kirk Alan Baldwin
Electronic Theses and Dissertations
Large quantities of whey are produced as a by-product from the manufacture of cheese or casein. The United States has an annual cheese production of about 2.2 billion kg. The cheese industry has also experienced a steady increase in cheese production of about 6% a year (44). In the process, nearly 18.1 billion kg of whey are produced. Whey was once a discarded product of little value to the cheese producers. With the advent of laws and regulations governing the disposal of whey, whey became a problem that had few solutions. Even today, with the high cost of disposal and …
Extruded Blend Of Soybean Meal And Sunflower Seeds For Dairy Cattle In Early Lactation, James K. Drackley
Extruded Blend Of Soybean Meal And Sunflower Seeds For Dairy Cattle In Early Lactation, James K. Drackley
Electronic Theses and Dissertations
An extruded blend of 44% crude protein soybean meal (50%), sunflower seeds (45%), and premix (5%) was evaluated as a protein and energy source for dairy cows in early lactation. Thirty Holstein cows (24 multiparos and 6 primiparous) were assigned to either a corn-oats-soybean meal concentrate (SBM) or a concentrate where soy-sunflower blend replaced all soybean meal and portions of corn and oats (SSF). Dry matter of total mixed diets was 36% corn silage, 21% alfalfa haylage, and 43% concentrate. Yields of milk (33.6 and 33.8 kg/day) and 4% fat-corrected milk (30.9 and 30.5 kg/day) were similar for cows fed …
Identification Of Volatile Compounds Produced By Brevibacterium Linens That Inhibit Molds, Samuel E. Beattie
Identification Of Volatile Compounds Produced By Brevibacterium Linens That Inhibit Molds, Samuel E. Beattie
Electronic Theses and Dissertations
Mold contamination of processed food and its raw ingredients is a major concern in agriculture. Although at one time mold contamination of cheese and other foods was considered to be of little conse9uence, discovery of carcinogenic and/or teratogenic toxins (73) produced by molds commonly associated with food has changed this innocuous and frequent inconvenience into a serious health consideration. The presence of mold on or in cheese is a common occurrence, indeed, many cheeses depend upon molds to provide characteristic cheese flavor and texture. Cheeses such as blue, Roquefort, Camembert, and Brie are ripened under controlled conditions by species of …
Comparative Nutritive Value Of Soybean Meal, Sunflower Meal, And Meat And Bone Meal For Egg Production, Smart M. Oruseibio
Comparative Nutritive Value Of Soybean Meal, Sunflower Meal, And Meat And Bone Meal For Egg Production, Smart M. Oruseibio
Electronic Theses and Dissertations
Two experiments were conducted over a period of two years to evaluate the comparative nutritive value of soybean meal, sunflower meal, and meat and bone meal. Experiment 1 consisted of 864 Babcock--3OO pullets randomly distributed into twelve diet treatments. Each treatment was replicated six-times with twelve birds per unit. Layers diets were formulated at 16, 14, and 12% protein levels with and without amino acid supplementation. The 12% amino acid supplemented level served as the control in the experiment. Soybean meal, sum-lower meal, and eat_ and bone meal were utilized as major sources of protein supplement in yellow-corn based diets. …
Effects Of Partial Homogenization Of Milk On Yield And Quality Of Cheddar Cheese, Anand Rao
Effects Of Partial Homogenization Of Milk On Yield And Quality Of Cheddar Cheese, Anand Rao
Electronic Theses and Dissertations
In the past decade, the cheese industry in the United States (US) has grown rapidly, with cheese sales increasing by 33% (36). The cheese industry, in 1983, utilized 29.2% of total US milkfat supply as compared to 20.3% utilization in 1973 (36). Compared to the total cheese production of 2,059,2Z8 kg (4,539,822 lb) in 1982, 2,185,611 kg (4,818,449 lb) of cheese were manufactured in 1983 in the .US (36). The increased production of cheese was made possible by modifications in the cheese making process and advent of modern equipment; and it was fostered by increased demand .and higher prices. One …
Evaluation Of Urea And Dried Whey In Diets Of Cows During Early Lactation, David Paul Casper
Evaluation Of Urea And Dried Whey In Diets Of Cows During Early Lactation, David Paul Casper
Electronic Theses and Dissertations
Previous research indicated that soluble nitrogen may be utilized more efficiently for rumen microbial production in diets containing dried whey. To further evaluate this, 33 Holstein, cows (30 multiparous and 3 primiparous) were fed one of three concentrate mixes containing all natural proteins (SBM). 1% urea (U), or 1% urea and 30% dried whey (UDW) from wk 3 through 16 postpartum. Urea replaced portions of the soybean meal in the SBM mix while dried whey replaced portions of the corn and soybean meal. Cows were fed total mixed rations consisting of 40% (dry matter basis) corn silage, 10% alfalfa hay, …
Protected Methionine And Heat-Treated Soybean Meal For High-Producing Dairy Cows, Che-Ming Jimmy Yang
Protected Methionine And Heat-Treated Soybean Meal For High-Producing Dairy Cows, Che-Ming Jimmy Yang
Electronic Theses and Dissertations
The effectiveness of a rumen-protected methionine preparation was studied as an amino acid source for high-producing dairy cows during wk 4 through 16 postpartum. Twenty-four Holstein cows (14 primiparous and 10 multiparous) were fed concentrate containing heat-treated· soybean meal without or with 50 g/cow/day of added ruminally protected methionine product which provided 15 g of added DL-methionine daily. Cows were fed 16% crude protein mixed diets containing 30% of dry matter as corn silage, 15% as alfalfa hay, and 55% as concentrate. Milk production and composition were adjusted for pretreatment values (3 wk postpartum) by analysis of covariance. Adjusted milk …