Digital Commons Network^™

Combinatorial Control Of Yeast Fet4 Gene Expression By Iron, Zinc, And Oxygen, Brian M. Waters, David J. Eide

Department of Agronomy and Horticulture: Faculty Publications

Acquisition of metals such as iron, copper, and zinc by the yeast Saccharomyces cerevisiae is tightly regulated. High affinity uptake systems are induced under metal-limiting conditions to maintain an adequate supply of these essential nutrients. Low affinity uptake systems function when their substrates are in greater supply. The FET₄ gene encodes a low affinity iron and copper uptake transporter. FET₄ expression is regulated by several environmental factors. In this report, we describe the molecular mechanisms underlying this regulation. First, we found that FET₄ expression is induced in iron-limited cells by the Aft1 iron-responsive transcriptional activator. Second, FET …

Ft-Nir Spectroscopic Analysis Of Nitrogen In Cotton Leaves, Mark R. Riley, Loreto C. Canaves

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Near-infrared spectroscopy was evaluated as a means to quantify the nitrogen content- in fresh cotton leaves (Gossypium hirsutum L. var. Delta Pine 90) subjected to a factorial design experiment of varying nitrogen and water applications. Absorbance spectra were collected in the 10000-4000 cm^-1 (1000-2500 nm) region from fresh cotton leaves over a two month portion of the growing season. Total nitrogen content was quantified by a wet chemistry Kjeldahl method for validation purposes. Partial least-squares regression analysis, using an automated grid search method, selected the spectral region 6041 to 5651 cm^-1 (1650-1770 nm) for analysis based on having …

Life History Response Of Mediterranean Fruit Flies To Dietary Restriction, James R. Carey, Pablo Liedo, Lawrence G. Harshman, Ying Zhang, Hans-Georg Müller, Linda Partridge, Jane-Ling Wang

Lawrence G. Harshman Publications

The purpose of this study was to investigate medfly longevity and reproduction across a broad spectrum of diet restriction using a protocol similar to those applied in most rodent studies. Age-specific reproduction and age of death were monitored for 1,200 adult males and 1,200 females, each individually maintained on one of 12 diets from ad libitum to 30% of ad libitum. Diet was provided in a fixed volume of solution that was fully consumed each day, ensuring control of total nutrient consumption for every fly. Contrary to expectation and precedence, increased longevity was not observed at any level of …

Food Pulses Increase Longevity And Induce Cyclical Egg Production In Mediterranean Fruit Flies, James R. Carey, Pablo Liedo, Lawrence G. Harshman, X. Liu, Hans-Georg Müller, Linda Partridge, Jane-Ling Wang

Lawrence G. Harshman Publications

1. Inasmuch as virtually all studies on mortality and reproduction in insects are conducted under conditions in which food availability is constant, little is known about the demographic response of insects to variable food environments. For example, it is not known if and to what extent the life expectancy of insects subjected to shortages of high-quality food will increase and/or whether this increase is associated with major decreases in lifetime reproduction.

2. Therefore cohorts of 100 individual female medflies were subjected to different sets of conditions of protein availability (interspersed with sugar-only diets) including ad libitum sugar-only (no protein), ad …

A Preliminary Analysis Of Proteolytic Activity Of Excretory-Secretory Products From Cyathostominea, Jane L. Kinsella, J. Ralph Lichtenfels, Michael F. Ryan

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The excretory-secretory product (ESP) derived from Cyathostominea in vitro was assessed, in terms of subunit composition, and proteolytic activity using as substrates azocasein and two synthetic fluorogenic peptides. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) resolved 13 subunits, and the presence of the protein cysteine proteinase activator dithiothreitol (DTT) revealed 21 subunits.DTTalso enhanced azocaseinolysis, and hydrolysis of carbobenzoxy-phenylalanyl-arginine-7-amido-4-methylcoumarin (Z-Phe-Arg-NHMec) and carbobenzoxy-arginyl-arginine-7-amido-4-methylcoumarin (Z-Arg-Arg-NHMec). At the optimum pH of 5.5, hydrolysis of Z-Phe-Arg-NHMec was three-fold greater than that of Z-Arg-Arg-NHMec suggesting that the proteolytic specificities of the ESP are more like those of papain or cathepsin L, rather than cathepsin B. In SDS-PAGE …

Relating Net Nitrogen Input In The Mississippi River Basin To Nitrate Flux In The Lower Mississippi River: A Comparison Of Approaches, Gregory F. Mcisaac, Mark B. David, George Z. Gertner, Donald A. Goolsby

United States Geological Survey: Staff Publications

A quantitative understanding of the relationship between terrestrial N inputs and riverine N flux can help guide conservation, policy, and adaptive management efforts aimed at preserving or restoring water quality. The objective of this study was to compare recently published approaches for relating terrestrial N inputs to the Mississippi River basin (MRB) with measured nitrate flux in the lower Mississippi River. Nitrogen inputs to and outputs from the MRB (1951 to 1996) were estimated from state-level annual agricultural production statistics and NO_y (inorganic oxides of N) deposition estimates for 20 states that comprise 90% of the MRB. A model …

Beet Armyworm (Lepidoptera: Noctuidae) Host Plant Preferences For Oviposition, S. M. Greenberg, T. W. Sappington, T.-X. Liu

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Beet armyworm, Spodoptera exigua (Hübner), oviposition preferences were determined on five host plants: cabbage (Brassica oleracea capitata L.), cotton (Gossypium hirsutum L.), bell pepper (Capsicum annuum L.), pigweed (Amaranthus retroflexus L.), and sunflower (Helianthus annuus L.) in no-choice, two-choice, and five-choice tests. Tests were conducted in the laboratory, greenhouse, and field cages. Oviposition preferences were compared on the basis of two measurements, the proportion of eggs laid on the plants to total that were deposited, and the oviposition preference index defined as [(number of eggs laid on the plant) - (number of eggs laid on …

Detecting Single Wheat Kernels Containing Live Or Dead Insects Using Near-Infrared Reflectance Spectroscopy, Elizabeth B. Maghirang, Floyd E. Dowell, James E. Baker, James E. Throne

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

An automated NIR system was used over a two-month storage period to detect single wheat kernels that contained live or dead internal rice weevils at various stages of growth. Correct classification of sound kernels and kernels containing live pupae, large larvae, medium-sized larvae, and small larvae averaged 94, 92, 84, and 62%, respectively. Pupae + large larvae calibrations were developed using live or dead internal insects. Validation results showed correct classifications ranging from 86 to 96% over the two-month storage period. Thus, wheat kernels containing either live or dead insects can be used to develop calibrations for detecting both live …

Seasonal Migration Of Columbia Spotted Frogs (Rana Luteiventris) Among Complementary Resources In A High Mountain Basin, David S. Pilliod, Charles R. Peterson, Peter I. Ritson

United States Geological Survey: Staff Publications

Information on how animals partition their activities and travel among complementary resources, such as breeding or overwintering habitats, is needed for species conservation. In a mountain basin at 2500 m elevation in central Idaho, we studied the habitat use and movement patterns of 736 marked and 87 radio-tagged Columbia spotted frogs (Rana luteiventris) from 1995 to 1998. The goals of this study were to (i) identify and characterize R. luteiventris breeding, summer foraging, and overwintering habitats, (ii) describe the movement patterns of juvenile, male, and female R. luteiventris among these resources, and (iii …

Managing Young Cows, Dick Pruitt

Range Beef Cow Symposium

In a recent analysis of SPA records from the Northern Great Plains, pregnancy percentage, calving percentage and weaning percentage were important production variables related to profit (Dunn, 2000). The high profit group did not wean heavier calves than the medium profit group. Consistent with other studies, the high profit group had lower investment and total expenditures per cow than the medium or low profit groups. Although describing what makes a cow-calf enterprise profitable is not as simple as we might like, there is strong evidence that relatively high reproductive rate in combination with low cost of production is a very …

The Role Of Undegradable Intake Protein In Management Of The Young Beef Female, Trey Patterson

Range Beef Cow Symposium

Reproductive failure in young cows is expensive to many beef operations in the Northern Great Plains. Scientists, nutritionists, and producers have typically placed great effort into heifer development and mature cow management at the expense of two- and three-year-old cows. Meek et al. (1999), working with a ranch in the Nebraska Sandhills, found that the net present value (current animal value accounting for time value of money) of beef females peaked at four years old. Why were bred heifers and pregnant two-year-olds not more valuable than four-year-old cows? Reproductive failure in the young cows did not allow them to stay …

Economics Of Young Female Management, Dillon M. Feuz

Range Beef Cow Symposium

What is the value of a heifer calf, a bred heifer, or a re-bred 2nd calf cow? How does that value compare to the current market price? What is your cost of raising a heifer calf, bred heifer, or re-bred 2nd calf cow? How many pencils have been worn dull or how many spreadsheets have been created to answer these questions? The unrealistic objective of this paper is to answer these questions. Perhaps a more realistic objective is to answer some of these questions and to provide you the framework to answer some of the questions for your own operation. …

Vertical Communication: The Aligning Of The Beef Industry Segments, Dave True

Range Beef Cow Symposium

During this presentation, I hope to convey why True Ranches, a family owned cow/calf producer and feeder in Wyoming has joined forces with Future Beef Operations (FBO). In brief summary, we believe that True Ranches fits well with FBO’s strategy and there is a clear, well identified target towards which the entire system is striving.

An Update On Clostridial Diseases/Abomasal Ulcers, R. G. Mortimer, R. P. Ellis

Range Beef Cow Symposium

Losses of calves in beef herds to Clostridial diseases continues to be a problem. In a large 1991 Colorado study of 47 herds with 11,767 cows reported that two of the most common causes of calf mortality were enteric and sudden death diseases. Both of these entities are consistent with Clostridial disease. Unfortunately, less than 1% of the calves that died were ever presented to a diagnostic lab for confirmation of death and 99% was based on producer perception. A smaller study conducted in 1992-93 of 15 beef herds in Colorado, Wyoming and Nebraska with 3,273 calves born attempted to …

Dna Assisted Selection – A Realistic Perspective, Daniel Pomp

Range Beef Cow Symposium

Breathtaking advances are occurring in the knowledge and understanding of the structure, sequence and function of DNA. The entire genetic blueprint, or DNA code, has now been deciphered for humans, mice and a variety of other organisms. This modern-day “Genomic Revolution” may be one of the most important periods in the scientific history of humankind, promising diagnostics and therapeutics for numerous diseases and maladies.

In animal agriculture, and particularly in beef cattle improvement, the payoffs of the “Genomic Revolution” have seemingly been few and far between. DNA information on cattle is now routinely used for determining parentage and for quality …

Objective Development Of Grazing Strategies, Patrick E. Reese

Range Beef Cow Symposium

A grazing strategy is a plan for accomplishing a set of objectives based on comprehensive knowledge of available resources, and the production and marketing environment. Management can be greatly simplified when grazing strategies are based on clearly stated and prioritized resource-management and livestock-production objectives (Fig. I ). Decisions on when and how to use plant resources have profound effects on the success of grazing strategies. Plant resources can be used for livestock production or wildlife cover and ecosystem functions such as hydrologic condition and site stability.

While many rangelands in the central and northern Great Plains are dominated by grasses …

The Value Of Corn As A Hay Replacement For Cows, Cody Wright

Range Beef Cow Symposium

In many western cattle operations, harvested forages have traditionally been considered the most economical feedstuffs for wintering beef cows. However, in certain situations, the nutrient content of standing or harvested forages may be inadequate to meet the nutritional requirements of the beef cow for maintenance, gestation, or lactation. Furthermore, the availability of standing or harvested forages may be limited, especially during drought years and(or) severe winters when the cost of medium- to low-quality forages may reach $80-100 per ton. Feeding corn grain may represent an economically viable alternative in each of these scenarios.

Producers commonly ask “how much corn can …

Effects Of Mineral Nutrition Of Immune Function And Factors That Affect Trace Mineral Requirements Of Beef Cattle, Terry E. Engle

Range Beef Cow Symposium

Trace minerals exist in cells and tissues of the animal body in a variety of chemical combinations, and in characteristic concentrations, which vary with the trace mineral and tissue (McDowell, 1989, 1992; Underwood and Suttle, 1999). The concentrations of trace minerals must usually be maintained within quite narrow limits if the functional and structural integrity of the tissue is to be maintained and the growth, health, and productivity of the animal are to remain unimpaired (McDowell, 1989, 1992; Underwood and Suttle, 1999). Ingestion of diets that are deficient, imbalanced, or excessively high in trace minerals may induce changes in the …

A Systems Approach To Production From Weaning To Harvest, Terry J. Klopfenstein, D. J. Jordon, Galen E. Erickson

Range Beef Cow Symposium

Although some summer and fall calving occurs, the majority of calves in the Northern States are born in the spring. Therefore, to have a consistent supply of feeders entering feedlots, a variety of stocker programs are used. About 30% of calves produced in the U. S. enter the feedlot as calf-feds. Some of these calf-feds are weaned and enter the feedlot 30 to 40 days later. It is also common for calves to be backgrounded two to six months before entering the feedlot.

Many calves enter yearling programs. These cattle are nutritionally restricted to varying degrees and for various times. …

A Cowboy’S Guide To Building Teams, Tom G. Field, Michael G. Hays

Range Beef Cow Symposium

One of the daunting challenges facing the cattle industry in the near term is the ability to attract and retain skilled and effective human resources to the ranching business. We currently have at our disposal vast amounts of information about marketing, health, reproduction, nutrition, genetics, forage management, and financial decision-making to create and sustain a viable cow-calf, stocker, or feedlot business. In fact, any of the existing enterprise managers in the industry likely excel in a majority of the aforementioned topics. However, one of the major obstacles to success in agriculture is a failure to recognize that human beings are …

University Of Nebraska Board Of Regents/ Academic Affairs Committee: Engagement With Community, John Owens

John Owens: Speeches and Appearances

Board of Regents and President Smith: It's a real pleasure to be able to discuss the University's role in engagement with you today on behalf of the four campuses that comprise the University of Nebraska.
In preparing this presentation I've drawn heavily upon the Kellogg Commission's report, entitled: "Returning to our Roots - The Engaged Institution," and the Michigan State University guidebook for planning-and-evaluating quality outreach, which is entitled: "Points of Distinction." I think both publications offer valuable insights as we explore the University's role as an engaged-partner with Nebraska.

Nebraska Cattlemen/Nebraska Cattle Women Conference, John Owens

John Owens: Speeches and Appearances

I’m so pleased to be here with you today, and I look forward to visiting and working with members of this group now and in the future. Since arriving in Nebraska nearly a year ago now on a snowy, blustery day, I’ve been delighted to take every opportunity that comes my way to get to know Nebraska and Nebraskans better. I want to know what you think are Nebraska’s greatest needs, now and in the future. I want to know how you think the University of Nebraska Institute of Agriculture and Natural Resources can help meet those needs. I seek …

Nebline, December 2001

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Bioterrorism and the Biosecurity Measures We Can Use to Reduce our Risks
Biosecurity Related NebGuides and NebFacts
Deicing Salts Harmful to Plants
Houseplant Problems
Horticulture information center
Growing Cacti and Succulents
How Do Honey Bees Survive the Winter?
Nothing Brightens up a Winter Day Like the Song of a Bird
Looking for a New Hobby? Learn to Manage Bees and Produce Honey!
Extension Resources on Feeding Birds and Wildlife Habitat
Fungus Gnats Are Nuisance Often Found in Soil of Houseplants
Producer Question — Should I Aerate my Pasture?
Management Pays Better than Labor
Biosolids Improves Soil and Cuts Production Costs …

Chronic Exposure Of The European Corn Borer (Lepidoptera: Crambidae) To Cry1ab Bacillus Thuringiensis Toxin, Josette Chafaux, Maryvonne Seguin, Jeffrey J. Swanson, Denis Bourguet, Blair D. Siegfried

Department of Entomology: Faculty Publications

Transgenic corn expressing the insecticidal toxin from Bacillus thuringiensis Berliner is gaining support as an effective control technology for use against lepidopteran pests, particularly European corn borer, Ostrinia nubilalis Hubner (Lepidoptera: Crambidae). However, there is concern that widespread adoption of transgenic plants will rapidly lead to B. thuringiensis toxin resistance. Thus, long-term selection of O. nubilalis populations with the Cry1Ab B. thuringiensis toxin has been undertaken in several laboratories in the United States and in Europe. We present results from two independent selection experiments performed in laboratories at the University of Nebraska and at the Institut National de la Recherche …

Identification Of A Cellular Protein That Interacts And Synergizes With The Rta (Orf50) Protein Of Kaposi’S Sarcoma-Associated Herpesvirus In Transcriptional Activation, Shizhen Wang, Shuhong Liu, Ming-Hoi Wu, Yunqi Geng, Charles Wood

Nebraska Center for Virology: Faculty Publications

Lytic reactivation of Kaposi’s sarcoma-associated herpesvirus (KSHV), or human herpesvirus 8, from latency requires transcriptional transactivation by the viral protein RTA encoded by the ORF50 gene. Very little is known about how RTA functions and the cellular factors that may be involved in its transactivation function. Using the yeast two-hybrid system, we have identified a human cellular protein that can interact with KSHV RTA. The cellular protein, referred to as the human hypothetical protein MGC2663 by GenBank, is encoded by human chromosome 19. This protein is 554 amino acids (aa) in size and displays sequence similarity with members of the …

Nebline, November 2001

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Celebrate Family Connections!
Take Time to be Thankful
Hints for Fruit Storage
Harvesting Popcorn
Winter Care For Strawberry Plants
Aloes, Easy and Fun to Grow
Horticulture information center
Pine Cones For Decoration
Combing: a Safe, Non-Toxic Method of Lice Control
Celebrate America Recycles Day
Head Lice Resources Available from the Extension Office
Asthma and Indoor Air Contaminants
Extension Record-Keeping Workshop Receives Award
Year End Financial Analysis and Planning
Beware of Entrapment in Moving Grain
Winterize Equipment Before Storing
Storing Leftover Pesticides
Heavy Water Use May Harm Septic Systems
Reduce Orchard Woes
Beware of Wood Heating Dangers]
T-U-R-K-E-Y Tips
Healthy Eating: …

Predicting Leaf/Stem Ratio And Nutritive Value In Grazed And Nongrazed Big Bluestem, Alexander J. Smart, Walter H. Schacht, Lowell E. Moser

Department of Agronomy and Horticulture: Faculty Publications

Recent advancements in describing morphological development of perennial grasses have provided a useful index for identifying dates to harvest hay or graze pasture. The objective of this study was to determine the relationship between big bluestem (Andropogon gerardii Vitman) morphological developmental stage, days from 1 May, and accumulated growing degree days (GDD) and leaf/stem ratio, crude protein (CP), and neutral detergent fiber (NDF) in grazed and nongrazed swards. The grazing experiment was conducted in eastern Nebraska during 1997 and 1998. Six grazing treatments consisting of all combinations of two herbage allowances (22 or 66 kg of herbage dry matter …

Deviant Behavior And Victimization Among Homeless And Runaway Adolescents, Les B. Whitbeck, Dan R. Hoyt, Kevin A. Yoder, Ana Mari Cauce, Matt Paradise

Department of Sociology: Faculty Publications

This study used a high-risk population of runaway and homeless adolescents to investigate the effects of history of caretaker abuse and deviant subsistence strategies on victimization among adolescents. Based on a multisite sample of 974 homeless and runaway adolescents, logistic regression models were used first to examine factors predicting involvement in sexual and nonsexual deviant subsistence strategies and then to investigate the effects of deviant subsistence strategies on physical and sexual victimization when adolescents were on the streets. Results indicated that when controlling for all other factors, including histories of physical and sexual maltreatment in families of origin, street behaviors, …

The Land Grant University Movement And The Future Of Ianr Uaad, John Owens

John Owens: Speeches and Appearances

Good afternoon. It is a real pleasure for me to be here with you today, and I thank you for inviting me. I also, as I begin my remarks today, want to thank each of you for the work you do, everyday, to help make this a better university. Please know that work is both valued and appreciated.
I'd like to talk with you about a couple of topics today, and after that I'm going to open the floor for questions and comments. I look forward to hearing what you have to say, too.
The first topic I'm going to …

Center For Grassland Studies Newsletter, Fall 2001, Volume 7, No. 4

Center for Grassland Studies: Newsletters

New Hosts of the Buffalograss Chinch Bug, Blissus occiduus by Thomas Eickhoff and Frederick Baxendale, Department of Entomology, UNL

Grassland Opportunities in the New Farm Bill by Craig Derickson, Natural Resources Conservation Service, USDA

Nebraska Grazing Conference Huge Success

Grazing Livestock Systems Major Enters Third Year

Great Plains Migrations Symposium

“Promoting Prairie” Conference in June 2002