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Characterization Of The Folate Salvage Enzyme P-Aminobenzoylglutamate Hydrolase In Plants, Gale G. Bozzo, Gilles J. C. Basset, Valeria Naponelli, Alexandre Noiriel, Jesse F. Gregory Iii, Andrew D. Hanson Jan 2008

Characterization Of The Folate Salvage Enzyme P-Aminobenzoylglutamate Hydrolase In Plants, Gale G. Bozzo, Gilles J. C. Basset, Valeria Naponelli, Alexandre Noiriel, Jesse F. Gregory Iii, Andrew D. Hanson

Department of Agronomy and Horticulture: Faculty Publications

Folates break down in vivo to give pterin and p-aminobenzoylglutamate (pABAGlu) fragments, the latter usually having a polyglutamyl tail. Pilot studies have shown that plants can hydrolyze pABAGlu and its polyglutamates to p-aminobenzoate, a folate biosynthesis precursor. The enzymatic basis of this hydrolysis was further investigated. pABAGlu hydrolase activity was found in all species and organs tested; activity levels implied that the proteins responsible are very rare. The activity was located in cytosol/vacuole and mitochondrial fractions of pea (Pisum sativum L.) leaves, and column chromatography of the activity from Arabidopsis tissues indicated at …


Whole-Plant Mineral Partitioning Throughout The Life Cycle In Arabidopsis Thaliana Ecotypes Columbia, Landsberg Erecta, Cape Verde Islands, And The Mutant Line Ysl1ysl3, Brian M. Waters, Michael A. Grusak Jan 2008

Whole-Plant Mineral Partitioning Throughout The Life Cycle In Arabidopsis Thaliana Ecotypes Columbia, Landsberg Erecta, Cape Verde Islands, And The Mutant Line Ysl1ysl3, Brian M. Waters, Michael A. Grusak

Department of Agronomy and Horticulture: Faculty Publications

Minimal information exists on whole-plant dynamics of mineral flow through Arabidopsis thaliana or on the source tissues responsible for mineral export to developing seeds. Understanding these phenomena in a model plant could help in the development of nutritionally enhanced crop cultivars. A whole-plant partitioning study, using sequential harvests, was conducted to characterize growth and mineral concentrations and contents of rosettes, cauline leaves, stems, immature fruit, mature fruit hulls, and seeds of three WT lines (Col-0, Ler, and Cvi) and one mutant line (Col-0::ysl1ysl3). Shoot mineral content increased throughout the life cycle for all minerals, although tissue-specific …


Comparison Of Lipid Extraction Methods Of Food-Grade Sorghum (Sorghum Bicolor) Using Hexane, K. L. Christiansen, Curtis L. Weller, V. L. Schlegel, I. M. Dweikat Jan 2008

Comparison Of Lipid Extraction Methods Of Food-Grade Sorghum (Sorghum Bicolor) Using Hexane, K. L. Christiansen, Curtis L. Weller, V. L. Schlegel, I. M. Dweikat

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Much has been reported concerning sorghum phytochemicals, such as policosanols, but little literature exists on how various extraction methods might be used to optimize the recovery of such phytochemicals. The purpose of this study was to compare three extraction methods for recovery of different sorghum lipids. Lipids were extracted from whole kernel and ground Macia, a food-grade sorghum hybrid, with hexane by a Soxtec method, a refluxing method (RB), and a bench-scale recirculated solvent (RC) method. Comparisons of total lipid yield and lipid class yields extracted from the grain by each method were made. Total lipid yield for the three …


Reduced Reliance On The Trace Element Selenium During Evolution Of Mammals, Alexey Lobanov, Dolph Hatfield, Vadim N. Gladyshev Jan 2008

Reduced Reliance On The Trace Element Selenium During Evolution Of Mammals, Alexey Lobanov, Dolph Hatfield, Vadim N. Gladyshev

Vadim Gladyshev Publications

Background: Selenium (Se) is an essential trace element that occurs in proteins in the form of selenocysteine (Sec). It is transported throughout the body in the form of Sec residues in Selenoprotein P (SelP), a plasma protein of unclear origin recently proposed as an experimental marker of dietary Se status.
Results: Here, we report that the amino-terminal domain of SelP is distantly related to ancestral bacterial thiol oxidoreductases of the thioredoxin superfamily, and that its carboxy-terminal Se transport domain may have originated in early metazoan evolution by de novo accumulation of Sec residues. Reconstruction of evolutionary changes in the Se …


A Functional Link Between Housekeeping Selenoproteins And Phase Ii Enzymes, Aniruddha Sengupta, Bradley A. Carlson, James A. Weaver, Sergey V. Novoselov, Dmitri E. Fomenko, Vadim N. Gladyshev, Dolph Hatfield Jan 2008

A Functional Link Between Housekeeping Selenoproteins And Phase Ii Enzymes, Aniruddha Sengupta, Bradley A. Carlson, James A. Weaver, Sergey V. Novoselov, Dmitri E. Fomenko, Vadim N. Gladyshev, Dolph Hatfield

Vadim Gladyshev Publications

Sec (selenocysteine) is biosynthesized on its tRNA and incorporated into selenium-containing proteins (selenoproteins) as the 21st amino acid residue. Selenoprotein synthesis is dependent on Sec tRNA and the expression of this class of proteins can be modulated by altering Sec tRNA expression. The gene encoding Sec tRNA (Trsp) is a single-copy gene and its targeted removal in liver demonstrated that selenoproteins are essential for proper function wherein their absence leads to necrosis and hepatocellular degeneration. In the present study, we found that the complete loss of selenoproteins in liver was compensated for by an enhanced expression of several phase II …


Identification Of A Consensus Dna-Binding Site For The Arabidopsis Thaliana Sbp Domain Transcription Factor, Atspl14, And Binding Kinetics By Surface Plasmon Resonance, Xinwen Liang, Tara J. Nazarenus, Julie M. Stone Jan 2008

Identification Of A Consensus Dna-Binding Site For The Arabidopsis Thaliana Sbp Domain Transcription Factor, Atspl14, And Binding Kinetics By Surface Plasmon Resonance, Xinwen Liang, Tara J. Nazarenus, Julie M. Stone

Department of Biochemistry: Faculty Publications

Proteins with a conserved Cys- and His-rich SQUAMOSA promoter binding protein (SBP) domain are transcription factors restricted to photosynthetic organisms that possess a novel two Zn-finger structure DNA-binding domain. Despite the fact that altered expression of some SBP-encoding genes has profound effects on organism growth and development, little is known about SBP domain protein target genes. Misexpression of the Arabidopsis thaliana AtSPL14 SBP domain gene confers resistance to programmed cell death and modifies plant architecture. A consensus DNA-binding motif for AtSPL14 was identified by systematic evolution of ligands by exponential enrichment (SELEX) or random binding site selection (RBSS). DNA recognized …


Comparative Metabolite Profiling Of Carboxylic Acids In Rat Urine By Ce-Esi Ms/Ms Through Positively Pre-Charged And 2H-Coded Derivatization, Wen-Chu Yang, Fred E. Regnier, Jiri Adamec Jan 2008

Comparative Metabolite Profiling Of Carboxylic Acids In Rat Urine By Ce-Esi Ms/Ms Through Positively Pre-Charged And 2H-Coded Derivatization, Wen-Chu Yang, Fred E. Regnier, Jiri Adamec

Department of Biochemistry: Faculty Publications

A new approach for the selective comparative metabolite profiling of carboxylic acids in rat urine was established using capillary electrophoresis-mass spectrometry (CE-MS) and a method for positively pre-charged and 2H-coded derivatization. Novel derivatizing reagents, N-alkyl-4-

aminomethylpyridinum iodide (alkyl=butyl, butyl-d9 or hexyl), containing quaternary amine and

stable isotope atoms (deuterium), were introduced for the derivatization of carboxylic acids. CE

separation in positive polarity showed high reproducibility (0.99 –1.32% RSD of migration time)

and eliminated problems with capillary coating known in CE-MS anion analyses. Essentially

complete ionization and increased hydrophobicity after the derivatization also enhanced MS

detection sensitivity (e.g. formic …


Regulation Of Aromatic Alcohol Production In Candida Albicans, Suman Ghosh, Bessie W. Kebaara, Audrey L. Atkin, Kenneth W. Nickerson Jan 2008

Regulation Of Aromatic Alcohol Production In Candida Albicans, Suman Ghosh, Bessie W. Kebaara, Audrey L. Atkin, Kenneth W. Nickerson

School of Biological Sciences: Faculty Publications

Colonization by the fungal pathogen Candida albicans varies significantly, depending upon the pH and availability of oxygen. Because of our interest in extracellular molecules as potential quorum-sensing molecules, we examined the physiological conditions which regulate the production of the aromatic alcohols, i.e., phenethyl alcohol, tyrosol, and tryptophol. The production of these fusel oils has been well studied for Saccharomyces cerevisiae. Our data show that aromatic alcohol yields for C. albicans are determined by growth conditions. These conditions include the availability of aromatic amino acids, the pH, oxygen levels, and the presence of ammonium salts. For example, for wild-type C. …


Pea Aphid, Jennifer A. Brisson, Gregory K. Davis Jan 2008

Pea Aphid, Jennifer A. Brisson, Gregory K. Davis

School of Biological Sciences: Faculty Publications

Aphids have long been of interest because of their complex life cycles, environmentally induced morphologies, and importance to agriculture. However, only recently has the resulting wealth of ecological and population genetic data begun to be supplemented by genomic and genetic mapping approaches. In 2004, the International Aphid Genomics Consortium, a collaboration of aphid researchers, chose to establish the pea aphid, Acyrthosiphon pisum, as the aphid of choice for the development of genomic resources. Here we introduce the pea aphid and discuss a number of biological questions for which the species is well suited. We then review previous mapping and quantitative …


The Genome Sequence Of The Metal-Mobilizing, Extremely Thermoacidophilic Archaeon Metallosphaera Sedula Provides Insights Into Bioleaching-Associated Metabolism, Kathryne S. Auernik, Yukari Maezato, Paul H. Blum, Robert M. Kelly Jan 2008

The Genome Sequence Of The Metal-Mobilizing, Extremely Thermoacidophilic Archaeon Metallosphaera Sedula Provides Insights Into Bioleaching-Associated Metabolism, Kathryne S. Auernik, Yukari Maezato, Paul H. Blum, Robert M. Kelly

School of Biological Sciences: Faculty Publications

Despite their taxonomic description, not all members of the order Sulfolobales are capable of oxidizing

reduced sulfur species, which, in addition to iron oxidation, is a desirable trait of biomining microorganisms.

However, the complete genome sequence of the extremely thermoacidophilic archaeon Metallosphaera sedula

DSM 5348 (2.2 Mb, _2,300 open reading frames [ORFs]) provides insights into biologically catalyzed metal

sulfide oxidation. Comparative genomics was used to identify pathways and proteins involved (directly or

indirectly) with bioleaching. As expected, the M. sedula genome contains genes related to autotrophic carbon

fixation, metal tolerance, and adhesion. Also, terminal oxidase cluster organization indicates the presence …


Ecological Genomics: Understanding Gene And Genome Function In The Natural Environment, M. C. Ungerer, L. C. Johnson, M. A. Herman Jan 2008

Ecological Genomics: Understanding Gene And Genome Function In The Natural Environment, M. C. Ungerer, L. C. Johnson, M. A. Herman

School of Biological Sciences: Faculty Publications

The field of ecological genomics seeks to understand the genetic mechanisms underlying responses of organisms to their natural environments. This is being achieved through the application of functional genomic approaches to identify and characterize genes with ecological and evolutionary relevance. By its very nature, ecological genomics is an interdisciplinary field. In this review, we consider the significance of this new area of study from both an ecological and genomic perspective using examples from the recent literature. We submit that by considering more fully an ecological context, researchers may gain additional insights into the underlying genetic basis of ecologically relevant phenotypic …


Presidential Address: Nothing Succeeds Like Excess, Steven A. Nadler Jan 2008

Presidential Address: Nothing Succeeds Like Excess, Steven A. Nadler

Harold W. Manter Laboratory of Parasitology: Faculty Publications

To the members of the American Society of Parasitologists, I offer my appreciation for the opportunity to serve as your president. When I was notified of my successful election as an officer, it brought to mind that famous remark by Adlai Stevenson who said, ‘‘In America, anybody can be president. That’s one of the risks you take.’’ So, what I initially perceived as somewhat of a risky venture, proved to be a more valuable and interesting experience than I anticipated. Let’s hope that my presidential address has a similar outcome.


Tricarboxylic Acid Cycle-Dependent Regulation Of Staphylococcus Epidermidis Polysaccharide Intercellular Adhesin Synthesis, Marat R. Sadykov, Michael E. Olson, Steven M. Halouska, Yefei Zhu, Paul D. Fey, Robert Powers, Greg A. Somerville Jan 2008

Tricarboxylic Acid Cycle-Dependent Regulation Of Staphylococcus Epidermidis Polysaccharide Intercellular Adhesin Synthesis, Marat R. Sadykov, Michael E. Olson, Steven M. Halouska, Yefei Zhu, Paul D. Fey, Robert Powers, Greg A. Somerville

Robert Powers Publications

Staphylococcus epidermidis is a major nosocomial pathogen primarily infecting immunocompromised individuals or those with implanted biomaterials (e.g., catheters). Biomaterial-associated infections often involve the formation of a biofilm on the surface of the medical device. In S. epidermidis, polysaccharide intercellular adhesin (PIA) is an important mediator of biofilm formation and pathogenesis. Synthesis of PIA is regulated by at least three DNA binding proteins (IcaR, SarA, and σB) and several environmental and nutritional conditions. Previously, we observed the environmental conditions that increased PIA synthesis decreased tricarboxylic acid (TCA) cycle activity. In this study, S. epidermidis TCA cycle mutants were …


Fumonisin Level In Corn-Based Food And Feed From Linxian County, A High-Risk Area For Esophageal Cancer In China, Jiansheng Wang, Ying Zhou, Wanbo Liu, Xiangcheng Zhu, Liangcheng Du, Qiaomei Wang Jan 2008

Fumonisin Level In Corn-Based Food And Feed From Linxian County, A High-Risk Area For Esophageal Cancer In China, Jiansheng Wang, Ying Zhou, Wanbo Liu, Xiangcheng Zhu, Liangcheng Du, Qiaomei Wang

Liangcheng Du Publications

The level of mycotoxin fumonisins in corn-based food and feed collected from Linxian County, a high-risk area for esophageal cancer in China, has been analyzed using high-performance liquid chromatographic coupled with evaporative laser scattering detector (HPLC-ELSD). A total of 104 corn kernel samples were obtained from local households, granaries, wholesale markets (central markets), and retail markets (stores and supermarkets). Fumonisin B1 (FB1) was detected in the samples from households, granaries, central markets, and stores, with a positive rate of 61.5%, 50%, 33.3%, and 17%, respectively. No fumonisin was detected in samples from the supermarket. The highest FB1 levels (0.30–3.20 μg/ …


Mechanisms Of Hemoglobin Adaptation To High Altitude Hypoxia, Jay F. Storz, Hideaki Moriyama Jan 2008

Mechanisms Of Hemoglobin Adaptation To High Altitude Hypoxia, Jay F. Storz, Hideaki Moriyama

Hideaki Moriyama Publications

Evidence from a number of vertebrate taxa suggests that modifications of hemoglobin (Hb) function may often play a key role in mediating an adaptive response to high altitude hypoxia. The respiratory functions of Hb are a product of the protein’s intrinsic O2-binding affinity and its interactions with allosteric effectors such as protons, chloride ions, CO2, and organic phosphates. Here we review several case studies involving high altitude vertebrates where it has been possible to identify specific mechanisms of Hb adaptation to hypoxia. In addition to comparative studies of Hbs from diverse animal species, functional studies of …


Mechanisms Of Hemoglobin Adaptation To High Altitude Hypoxia, Jay F. Storz, Hideaki Moriyama Jan 2008

Mechanisms Of Hemoglobin Adaptation To High Altitude Hypoxia, Jay F. Storz, Hideaki Moriyama

Hideaki Moriyama Publications

Evidence from a number of vertebrate taxa suggests that modifications of hemoglobin (Hb) function may often play a key role in mediating an adaptive response to high altitude hypoxia. The respiratory functions of Hb are a product of the protein’s intrinsic O2-binding affinity and its interactions with allosteric effectors such as protons, chloride ions, CO2, and organic phosphates. Here we review several case studies involving high altitude vertebrates where it has been possible to identify specific mechanisms of Hb adaptation to hypoxia. In addition to comparative studies of Hbs from diverse animal species, functional studies of …


Parasite Pathoecology Of Salmon Pueblo And Other Chacoan Great Houses: The Healthiest And Wormiest Ancestral Puebloans, Karl Reinhard Jan 2008

Parasite Pathoecology Of Salmon Pueblo And Other Chacoan Great Houses: The Healthiest And Wormiest Ancestral Puebloans, Karl Reinhard

Karl Reinhard Publications

Two fields of paleopathological investigation originated in the Southwest. Archaeoparasitology is the study of ancient parasite infection (Reinhard 1990, 1992b). It includes comparisons between time periods of single societies as well as comparisons of parasitism between different, contemporaneous cultures. For example, Fry (1980) compared Fremont and Anasazi parasitism, and also Archaic hunter-gatherer and ancestral Pueblo parasitism. All of these studies fall into the definition of archaeoparasitology.

By contrast, pathoecology is the reconstruction of relationships among behavior, environment, and disease organisms in the development of illness (Martinson et al. 2003; ReinhardandBuikstra2003; Reinhardet al. 2003; Santoro et al. 2003).1his field developed from …


Pathoecology And The Future Of Coprolite Studies In Bioarchaeology, Karl J. Reinhard, Vaughn M. Bryant Jr. Jan 2008

Pathoecology And The Future Of Coprolite Studies In Bioarchaeology, Karl J. Reinhard, Vaughn M. Bryant Jr.

Karl Reinhard Publications

Human coprolites currently provide an expanding array of information about the diet, health, and ecology of prehistoric people in the Southwest, but for many years coprolites were not recognized or preserved, or they were not considered important and thus were not saved (Bryant and Dean 2006). With the expansion of archaeological field work during the last half of the twentieth century archaeologists have increasingly explored the "complete" potentials of sites, including the collection and analysis of geomorphologic, botanical, and faunal data. In some ideal habitats (e.g., very dry or frozen) this includes exploring the scientific potential of human coprolite studies. …


Pathoecology Of Two Ancestral Pueblo Villages, Karl Reinhard Jan 2008

Pathoecology Of Two Ancestral Pueblo Villages, Karl Reinhard

Karl Reinhard Publications

Pathoecology is the study of the biotic, abiotic, and cultural environments of disease (Martinson et al. 2003). A parasitic infection is the result of the pathoecological interaction of host behavior, parasite life cycle, the environment in which both life forms live, the nutritional status of the host, and host physiological responses to all of these factors. Parasites contribute to anemia in many ways. Some, such as hookworm, actually consume blood and cause iron loss through their activities. For other parasites, symptoms such as profuse diarrhea reduce intestinal absorption of nutrients. Others, such as certain fish tapeworms, actually compete for absorption …


The New Empirical Biopolitics, John R. Alford, John R. Hibbing Jan 2008

The New Empirical Biopolitics, John R. Alford, John R. Hibbing

Department of Political Science: Faculty Publications

Political science traditionally has either ignored biology in favor of purely environmental explanations for political phenomena or merely ruminated about the likely role of biology, leaving data-based research on biopolitics in dangerously short supply. Currently, attention to the apparent genetic basis for political and social orientations holds the greatest promise of advancing empirical biopolitics. Thus, in this essay, we orient behavior genetics research in the larger framework of biology and politics, confront its normative implications, describe the techniques involved, assess the strengths and weaknesses of commonly employed data and procedures, and describe the next steps in this research stream. Because …


Avoidance Of Hydrolyzed Casein By Mice, Kristin L. Field, Bruce A. Kimball, Julie A. Mennella, Gary K. Beauchamp, Alexander A. Bachmanov Jan 2008

Avoidance Of Hydrolyzed Casein By Mice, Kristin L. Field, Bruce A. Kimball, Julie A. Mennella, Gary K. Beauchamp, Alexander A. Bachmanov

United States Department of Agriculture Wildlife Services: Staff Publications

When casein, a milk protein, is hydrolyzed, it renders human foods that contain it (e.g., hypoallergenic infant formula, cheeses) distasteful to many people. This rejection of hydrolyzed casein (HC)-containing foods has recently been found to also occur in a non-human species (deer, Odocoileus spp.). Identifying other animals that avoid HC would facilitate understanding how and why HC-containing food is often rejected. This study determined whether HC-containing food is avoided by Mus musculus and whether consumption patterns were sensitive to testing conditions, specifically food form (powder, pellet or dough) and food access (ad libitum or 1.5 h/day following 6 h …


Winter Cover Crops And Vinegar For Early-Season Weed Control In Sustainable Cotton, P. J. Moran, S. M. Greenberg Jan 2008

Winter Cover Crops And Vinegar For Early-Season Weed Control In Sustainable Cotton, P. J. Moran, S. M. Greenberg

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

Weeds may be suppressed by winter cover crops and the use of organic herbicides such as vinegar. Black oat (Avena strigosa) and hairy vetch (Vicia villosa) winter cover crops were planted for 2 years as part of a sustainable production system for cotton in the Lower Rio Grande Valley of Texas, and were till-killed each spring prior to cotton planting. Palmer amaranth (Amaranthus palmeri), common purslane (Portulaca oleracea), and sunflower (Helianthus annuus) were frequently-encountered winter and spring weeds. Both cover crops controlled winter weeds as well as did winter tillage …


Babbling, Chewing, And Sucking: Oromandibular Coordination At 9 Months, Roger W. Steeve, Christopher A. Moore, Jordan R. Green, Kevin J. Reilly, Jacki Ruark Mcmurtrey Jan 2008

Babbling, Chewing, And Sucking: Oromandibular Coordination At 9 Months, Roger W. Steeve, Christopher A. Moore, Jordan R. Green, Kevin J. Reilly, Jacki Ruark Mcmurtrey

Department of Special Education and Communication Disorders: Faculty Publications

Purpose: The ontogeny of mandibular control is important for understanding the general neurophysiologic development for speech and alimentary behaviors. Prior investigations suggest that mandibular control is organized distinctively across speech and nonspeech tasks in 15-month-olds and adults and that, with development, these extant forms of motor control primarily undergo refinement and rescaling. The present investigation was designed to evaluate whether these coordinative infrastructures for alimentary behaviors and speech are evident during the earliest period of their co-occurrence.
Method: Electromyographic (EMG) signals were obtained from the mandibular muscle groups of 15 typically developing 9-month-old children during sucking, chewing, and speech.
Results: …


Respiratory Treatment History Predicts Suck Pattern Stability In Preterm Infants, Meredith Poore, Steven M. Barlow, Jingyan Wang, Mereditch Estep, Jaehoon Lee Jan 2008

Respiratory Treatment History Predicts Suck Pattern Stability In Preterm Infants, Meredith Poore, Steven M. Barlow, Jingyan Wang, Mereditch Estep, Jaehoon Lee

Department of Special Education and Communication Disorders: Faculty Publications

Sensory deprivation and motor restriction associated with extensive oxygen therapy may lead to poor oromotor control in preterm infants. Non-nutritive suck is one of the first complex oromotor behaviors infants perform. This study determined the spatiotemporal variability of non-nutritive suck (NNS) pressure trajectories in three preterm groups with differing oxygen histories—one control group with minimal or no O2 therapy, and two Respiratory Distress Syndrome (RDS) groups with either a mild/moderate (RDS1) or moderate/severe (RDS2) O2 history. The Non-nutritive Suck Spatiotemporal Index (NNS STI) quantifies spatial and temporal variability across kinematic trajectories, and was calculated from digital representations of …


Influence Of Plankton Mercury Dynamics And Trophic Pathways On Mercury Concentrations Of Top Predator Fish Of A Mining-Impacted Reservoir, A. Robin Stewart, Michael K. Saiki, James S. Kuwabara, Charles N. Alpers, Mark Marvin-Dipasquale, David P. Krabbenhoft Jan 2008

Influence Of Plankton Mercury Dynamics And Trophic Pathways On Mercury Concentrations Of Top Predator Fish Of A Mining-Impacted Reservoir, A. Robin Stewart, Michael K. Saiki, James S. Kuwabara, Charles N. Alpers, Mark Marvin-Dipasquale, David P. Krabbenhoft

United States Geological Survey: Staff Publications

Physical and biogeochemical characteristics of the aquatic environment that affect growth dynamics of phytoplankton and the zooplankton communities that depend on them may also affect uptake of methylmercury (MeHg) into the pelagic food web of oligotrophic reservoirs. We evaluated changes in the quality and quantity of suspended particulate material, zooplankton taxonomy, and MeHg concentrations coincident with seasonal changes in water storage of a mining-impacted reservoir in northern California, USA. MeHg concentrations in bulk zooplankton increased from 4 ng·g–1 at low water to 77 ± 6.1 ng·g–1 at high water and were positively correlated with cladoceran biomass (r = …


Boselaphus Tragocamelus (Artiodactyla: Bovidae), David M. Leslie Jr. Jan 2008

Boselaphus Tragocamelus (Artiodactyla: Bovidae), David M. Leslie Jr.

United States Geological Survey: Staff Publications

Boselaphus tragocamelus (Pallas, 1766) is a bovid commonly called the nilgai or blue bull and is Asia’s largest antelope. A sexually dimorphic ungulate of large stature and unique coloration, it is the only species in the genus Boselaphus. It is endemic to peninsular India and small parts of Pakistan and Nepal, has been extirpated from Bangladesh, and has been introduced in the United States (Texas), Mexico, South Africa, and Italy. It prefers open grassland and savannas and locally is a significant agricultural pest in India. It is not of special conservation concern and is well represented in zoos and …


Management And Conservation Note: Conserving Waste Rice For Wintering Waterfowl In The Mississippi Alluvial Valley, Jennifer P. Kross, Richard M. Kaminski, Aaron T. Pearse Jan 2008

Management And Conservation Note: Conserving Waste Rice For Wintering Waterfowl In The Mississippi Alluvial Valley, Jennifer P. Kross, Richard M. Kaminski, Aaron T. Pearse

United States Geological Survey: Staff Publications

The Mississippi Alluvial Valley (MAV), USA, is an internationally important migration and wintering region for North American waterfowl (Reinecke et al. 1989). The Lower Mississippi Valley Joint Venture (LMVJV) assumes food availability is the primary factor influencing carrying capacity of wintering waterfowl in this region (Reinecke and Loesch 1996). Because much of the MAV was converted from a seasonally flooded bottomland-hardwood ecosystem to a landscape dominated by agriculture, the LMVJV has incorporated estimates of the abundance of agricultural seeds such as rice into habitat conservation plans (Reinecke et al. 1988, Fredrickson et al. 2005). Biologists designed these plans to provide …


Omtvedt Innovation Award Winners, John Owens Jan 2008

Omtvedt Innovation Award Winners, John Owens

John Owens: Speeches and Appearances

It is a wonderful pleasure to have this opportunity today to present, two Omtvedt Innovation Awards to Institute colleagues whose outstanding work is a source of tremendous pride and inspiration for us all.


Asas Centennial Paper: Net Energy Systems For Beef Cattle – Cattles, Application, And Future Models, Calvin Ferrell, J. W. Oltjen Jan 2008

Asas Centennial Paper: Net Energy Systems For Beef Cattle – Cattles, Application, And Future Models, Calvin Ferrell, J. W. Oltjen

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

Development of nutritional energetics can be traced to the 1400s. Lavoisier established relationships among O2 use, CO2 production and heat production in the late 1700s, and the laws of thermodynamics and law of Hess were discovered during the 1840s. Those discoveries established the fundamental bases for nutritional energetics and enabled the fundamental entity ME = retained energy + heat energy to be established. Objectives became: 1) to establish relationships between gas exchange and heat energy, 2) to devise bases for evaluation of foods that could be related to energy expenditures, and 3) to establish causes of energy expenditures. …


Chapter 4. Relationship Of Environmental Nitrogen Metabolism To Human Health, J. R. Follett, R. F. Follett Jan 2008

Chapter 4. Relationship Of Environmental Nitrogen Metabolism To Human Health, J. R. Follett, R. F. Follett

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

The need for humans to produce and consume food and other agricultural products is increasing. This need is directly related to increasing world populations, demands for goods and services, and expectations. Nitrogen (N) is contained in all of the amino acids and proteins in the foods consumed by humans. The use of N to produce food and other products is generally increasing as human needs increase. Proteins are an essential component of the human diet because, unlike plants, humans are unable to utilize more simple forms of N and rely on food sources for protein which can then be digested …