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Adoption Of Breeding Technologies In The U.S. Dairy Industry And Their Influences On Farm Profitability, Aditya Raj Khanal 2010 Louisiana State University and Agricultural and Mechanical College

Adoption Of Breeding Technologies In The U.S. Dairy Industry And Their Influences On Farm Profitability, Aditya Raj Khanal

LSU Master's Theses

Current trends in the U. S. dairy industry show an increase in milk cows per farm and milk production per cow, though the total number of milk cows in the industry is declining. This increase in productivity is attributed to advancements and adoption of modern dairy technologies. Breeding technologies are one of the important components of this structural change. This study analyzed the factors affecting the adoption of modern breeding technologies such as artificial insemination, embryo transplants, and sexed semen, and the impact of these technologies on farm productivity and profitability. Results of a bivariate probit model with selection showed ...


Effects Of Varying Levels Of Cottonseed Hulls On Growth And Metabolic Indications Of Rumen Development Of Dairy Calves, Ryan Doescher 2010 Louisiana State University and Agricultural and Mechanical College

Effects Of Varying Levels Of Cottonseed Hulls On Growth And Metabolic Indications Of Rumen Development Of Dairy Calves, Ryan Doescher

LSU Master's Theses

A study was conducted to determine the effects of varying levels of cottonseed hulls on growth and metabolic indications of rumen development of dairy calves. Sixty-four Holstein calves (Heifers, n=40; Bulls, n=24) were randomly assigned to one of four dietary treatments which included calf starters containing no cottonseed hulls (control; C), 10% cottonseed hulls (10% CSH), 15% cottonseed hulls (15% CSH), or 20% cottonseed hulls (20% CSH). Calves were fed their respective treatments beginning on day 6 until day 56 of age. Body weights were measured at birth and biweekly thereafter until day 56 of age. Wither and ...


From Energy Gradient And Natural Selection To Biodiversity And Stability Of Ecosystems, Bo Deng 2010 University of Nebraska - Lincoln

From Energy Gradient And Natural Selection To Biodiversity And Stability Of Ecosystems, Bo Deng

Faculty Publications, Department of Mathematics

The purpose of this paper is to incorporate well-established ecological principles into a foodweb model consisting of four trophic levels --- abiotic resources, plants, herbivores, and carnivores. The underlining principles include Kimura's neutral theory of genetic evolution, Liebig's Law of the Minimum for plant growth, Holling's functionals for herbivore foraging and carnivore predation, the One-Life Rule for all organisms, and Lotka-Volterra's model for intraand interspecific competitions. Numerical simulations of the model led to the following statistical findings: (a) particular foodwebs can give contradicting observations on biodiversity and productivity, in particular, all known functional forms -- - positive, negative, sigmoidal ...


Metastability And Plasticity In A Conceptual Model Of Neurons, Bo Deng 2010 University of Nebraska - Lincoln

Metastability And Plasticity In A Conceptual Model Of Neurons, Bo Deng

Faculty Publications, Department of Mathematics

For a new class of neuron models we demonstrate here that typical membrane action potentials and spike-bursts are only transient states but appear to be asymptotically stable; and yet such metastable states are plastic — being able to dynamically change from one action potential to another with different pulse frequencies and from one spike-burst to another with different spike-per-burst numbers. The pulse and spike-burst frequencies change with individual ions’ pump currents while their corresponding metastable-plastic states maintain the same transmembrane voltage and current profiles in range. It is also demonstrated that the plasticity requires two one-way ion pumps operating in opposite ...


Crystal Structures Of The Cusa Efflux Pump Suggest Methionine-Mediated Metal Transport, Feng Long, Chih-Chia Su, Michael T. Zimmermann, Scott E. Boyken, Kanagalaghatta R. Rajashankar, Robert L. Jernigan, Edward W. Yu 2010 Iowa State University

Crystal Structures Of The Cusa Efflux Pump Suggest Methionine-Mediated Metal Transport, Feng Long, Chih-Chia Su, Michael T. Zimmermann, Scott E. Boyken, Kanagalaghatta R. Rajashankar, Robert L. Jernigan, Edward W. Yu

Biochemistry, Biophysics and Molecular Biology Publications

Gram-negative bacteria, such as Escherichia coli, frequently utilize tripartite efflux complexes in the resistance-nodulation-cell division (RND) family to expel diverse toxic compounds from the cell.1,2 The efflux system CusCBA is responsible for extruding biocidal Cu(I) and Ag(I) ions.3,4 No prior structural information was available for the heavy-metal efflux (HME) subfamily of the RND efflux pumps. Here we describe the crystal structures of the inner membrane transporter CusA in the absence and presence of bound Cu(I) or Ag(I). These CusA structures provide important new structural information about the HME sub-family of RND efflux ...


Structural Interpretation Of Protein-Protein Interaction Network, Ataur R. Katebi, Andrzej Kloczkowski, Robert L. Jernigan 2010 Iowa State University

Structural Interpretation Of Protein-Protein Interaction Network, Ataur R. Katebi, Andrzej Kloczkowski, Robert L. Jernigan

Biochemistry, Biophysics and Molecular Biology Publications

Background

Currently a huge amount of protein-protein interaction data is available from high throughput experimental methods. In a large network of protein-protein interactions, groups of proteins can be identified as functional clusters having related functions where a single protein can occur in multiple clusters. However experimental methods are error-prone and thus the interactions in a functional cluster may include false positives or there may be unreported interactions. Therefore correctly identifying a functional cluster of proteins requires the knowledge of whether any two proteins in a cluster interact, whether an interaction can exclude other interactions, or how strong the affinity between ...


High Tunnel Strawberry Production, Dan Drost, Brent Black 2010 Utah State University

High Tunnel Strawberry Production, Dan Drost, Brent Black

All Current Publications

This publication provides information on growing high tunnel strawberries including site preparation, site and irrigation management, and planting dates and spacing.


Two Rings In Them All: The Labdane-Related Diterpenoids, Reuben J. Peters 2010 Iowa State University

Two Rings In Them All: The Labdane-Related Diterpenoids, Reuben J. Peters

Biochemistry, Biophysics and Molecular Biology Publications

In his original exposition of the biogenetic isoprenoid rule, L. Ruzicka noted the structural identity between the fused A/B rings of triterpenoids/sterols and certain multicyclic diterpenoids as part of the impetus leading to that profound insight. His prescient hypothesis that this chemical structure relationship reflects similarities in the initial cyclization of these diterpenoids with that occurring in triterpenoid biosynthesis has since been verified. However, this chemical structure relationship does not continue to hold true for the additional rings found in many of these di- and tri- terpenoid natural products. This is now appreciated to arise from differences in ...


Effects Of Meal Timing On Anabolic Hormone Status And Energy Metabolism In Neonatal Dairy Calves, Katherine Claire Simon 2010 Louisiana State University and Agricultural and Mechanical College

Effects Of Meal Timing On Anabolic Hormone Status And Energy Metabolism In Neonatal Dairy Calves, Katherine Claire Simon

LSU Master's Theses

Twelve neonatal Holstein bull calves (38.52 ± 5.87 kg) were fed milk replacer at a fixed or varied meal time to determine the effects on metabolic hormone secretion, average daily intake, growth, and energy metabolism. Body weights were measured every two weeks from birth to 8 weeks. Rumen fluid was collected every two weeks from week 2 through 8. Serial blood collections were conducted every two weeks from week 2 through 8. Blood was collected, beginning at 0530, at 0, 15, 30, 45, 60, 75, 90, 105, 120, 135, and 150 minutes. Plasma was analyzed for ghrelin, leptin, growth ...


Observations Of Distribution, Size, And Sex Ratio Of Mature Blue Crabs, Callinectes Sapidus, From A Chesapeake Bay Tributary In Relation To Oyster Habitat And Environmental Factors, JM Harding, R Mann 2010 Virginia Institute of Marine Science

Observations Of Distribution, Size, And Sex Ratio Of Mature Blue Crabs, Callinectes Sapidus, From A Chesapeake Bay Tributary In Relation To Oyster Habitat And Environmental Factors, Jm Harding, R Mann

VIMS Articles

Blue crabs Callinectes sapidus (Rathbun, 1896) > 100 mm carapace width were sampled from a constructed oyster reef (1996 and 1997), a sand bar (1997) and a natural oyster bar (1997) in the Piankatank River, Chesapeake Bay, USA to describe habitat use, sex ratios, and demographics across a gradient of habitat types. Patterns of blue crab catch-per-unit-effort (CPUE), and demographics were similar on the oyster reef in 1996 and 1997. Average annual CPUE on the reef was 6-8 crabs pot(-1) with maximum CPUE of 15 crabs pot(-1). Daylength and water temperature significantly affected reef CPUE with more crabs observed ...


Synthesis Of (±)-Nosyberkol (Isotuberculosinol, Revised Structure Of Edaxadiene) And (±)-Tuberculosinol, Nathan Maugel, Francis M. Mann, Matthew L. Hillwig, Reuben J. Peters, Barry B. Snider 2010 Brandeis University

Synthesis Of (±)-Nosyberkol (Isotuberculosinol, Revised Structure Of Edaxadiene) And (±)-Tuberculosinol, Nathan Maugel, Francis M. Mann, Matthew L. Hillwig, Reuben J. Peters, Barry B. Snider

Biochemistry, Biophysics and Molecular Biology Publications

Me2AlCl-catalyzed Diels-Alder reaction of N-tigloyloxazolidinone with 6,6-dimethyl-1-vinylcyclohexene selectively provided the exo adduct, which was converted to nosyberkol (isotuberculosinol) and tuberculosinol. The spectral data for nosyberkol are identical with those reported for edaxadiene, whose structure is revised accordingly.


The Reflect Statement: Methods And Processes Of Creating Reporting Guidelines For Randomized Controlled Trials For Livestock And Food Safety, Annette M. O'Connor, Jan M. Sargeant, I. A. Gardner, James S. Dickson, Mary E. Torrence, C. E. Dewey, Ian R. Dohoo, R. B. Evans, J. T. Gray, Mattias Greiner, Greg Keefe, Sandra L. Lefebvre, Paul S. Morley, Alejandro Ramirez, William Sischo, D. R. Smith, Kate Snedeker, John N. Sofos, M. P. Ward, Robert W. Wills 2010 Iowa State University

The Reflect Statement: Methods And Processes Of Creating Reporting Guidelines For Randomized Controlled Trials For Livestock And Food Safety, Annette M. O'Connor, Jan M. Sargeant, I. A. Gardner, James S. Dickson, Mary E. Torrence, C. E. Dewey, Ian R. Dohoo, R. B. Evans, J. T. Gray, Mattias Greiner, Greg Keefe, Sandra L. Lefebvre, Paul S. Morley, Alejandro Ramirez, William Sischo, D. R. Smith, Kate Snedeker, John N. Sofos, M. P. Ward, Robert W. Wills

Veterinary Diagnostic and Production Animal Medicine Publications

The conduct of randomized controlled trials in livestock with production, health, and foodsafety outcomes presents unique challenges that may not be adequately reported in trial reports. The objective of this project was to modify the CONSORT (Consolidated Standards of Reporting Trials) statement to reflect the unique aspects of reporting these livestock trials. A two-day consensus meeting was held on November 18–19, 2008 in Chicago, IL, United States of America, to achieve the objective. Prior to the meeting, a Web-based survey was conducted to identify issues for discussion. The 24 attendees were biostatisticians, epidemiologists, food-safety researchers, livestock-production specialists, journal editors ...


Application Of Systematic Review Methodology To Food And Feed Safety Assessments To Support Decision Making, Jonathan J. Deeks, Geoff K. Frampton, Julie M. Glanville, Mattias Greiner, Julian P. T. Higgins, Gabor Lövei, Annette M. O'Connor, Andrew S. Pullin, Andrijana Rajić 2010 University of Birmingham

Application Of Systematic Review Methodology To Food And Feed Safety Assessments To Support Decision Making, Jonathan J. Deeks, Geoff K. Frampton, Julie M. Glanville, Mattias Greiner, Julian P. T. Higgins, Gabor Lövei, Annette M. O'Connor, Andrew S. Pullin, Andrijana Rajić

Veterinary Diagnostic and Production Animal Medicine Publications

Systematic reviews are commonly used in human health research to provide overviews of existing evidence pertinent to clearly formulated specific questions, using pre-specified and standardised methods to identify and critically appraise relevant research, and to collect, report and analyse data from the studies that are included in the reviews. Formal systematic reviews have rarely been used in food and feed safety risk assessments and the existing systematic review methods in other disciplines may not be directly applicable in this field. This Guidance aims to assist the application of systematic reviews to food and feed safety risk assessments in support of ...


The Impact Of Conservation On The Status Of The World's Vertebrates, M Hoffmann, C Hilton-Taylor, A Angulo, M Bohm, TM Brooks, Et al. 2010 William & Mary

The Impact Of Conservation On The Status Of The World's Vertebrates, M Hoffmann, C Hilton-Taylor, A Angulo, M Bohm, Tm Brooks, Et Al.

VIMS Articles

Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to ...


Changes In Age Composition And Growth Characteristics Of Atlantic Sturgeon (Acipenser Oxyrinchus Oxyrinchus) Over 400 Years, MT Balazik, GC Garman, ML Fine, CH Hager, SP McIninch 2010 Virginia Institute of Marine Science

Changes In Age Composition And Growth Characteristics Of Atlantic Sturgeon (Acipenser Oxyrinchus Oxyrinchus) Over 400 Years, Mt Balazik, Gc Garman, Ml Fine, Ch Hager, Sp Mcininch

VIMS Articles

Populations of sturgeon (Acipenseridae) have experienced global declines, and in some cases extirpation, during the past century. In the current era of climate change and over-harvesting of fishery resources, climate models, based on uncertain boundary conditions, are being used to predict future effects on the Earth's biota. A collection of approximately 400-year-old Atlantic sturgeon spines from a midden in colonial Jamestown, VA, USA, allowed us to compare the age structure and growth rate for a pre-industrial population during a 'mini-ice age' with samples collected from the modern population in the same reach of the James River. Compared with modern ...


Science-To-Management Pathways In Us Atlantic Herring Management: Using Governance Network Structure And Function To Track Information Flow And Potential Influence, TW Hartley, C Glass 2010 Virginia Institute of Marine Science

Science-To-Management Pathways In Us Atlantic Herring Management: Using Governance Network Structure And Function To Track Information Flow And Potential Influence, Tw Hartley, C Glass

VIMS Articles

Hartley, T. W., and Glass, C. 2010. Science-to-management pathways in US Atlantic herring management: using governance network structure and function to track information flow and potential influence. - ICES Journal of Marine Science, 67: 1154-1163. Atlantic herring (Clupea harengus) are crucial members of the ecosystem and economy of the Northwest Atlantic, and a challenging species for management, which in the United States is a multistakeholder process, involving commercial and recreational fishing interests, conservation organizations, state and federal governments, and other interested parties. Given the large number of stakeholders, fisheries management has been conceptualized as a governance network, through which multiple parties ...


Controlling Excess Capacity In Common-Pool Resource Industries: The Transition From Input To Output Controls, D Squires, Y Jeon, RQ Grafton, J Kirkley 2010 Virginia Institute of Marine Science

Controlling Excess Capacity In Common-Pool Resource Industries: The Transition From Input To Output Controls, D Squires, Y Jeon, Rq Grafton, J Kirkley

VIMS Articles

Overcapacity is a major problem in common-pool resources. Regulators increasingly turn from limited entry to individual transferable use rights to address overcapacity. Using individual vessel data from before and after the introduction of individual harvest rights into a fishery, the paper investigates how characteristics of rights, scale of operations and transition period affect changes in individual and fleet capacity utilisation and excess capacity. The results indicate that individual harvest rights in both theory and practice offer the potential to address the problem of overcapacity in common-pool resources currently managed with limited-entry regulations.


An Expansion Of The Msvpa Approach For Quantifying Predator-Prey Interactions In Exploited Fish Communities, LP Garrison, JS Link, DP Kilduff, MD Cieri, B Maffley, RJ Latour, Et al. 2010 Virginia Institute of Marine Science

An Expansion Of The Msvpa Approach For Quantifying Predator-Prey Interactions In Exploited Fish Communities, Lp Garrison, Js Link, Dp Kilduff, Md Cieri, B Maffley, Rj Latour, Et Al.

VIMS Articles

Ecosystem-based fisheries management requires tools to place fish-stock dynamics in the broader context of fishery, predator, and competitive removals. Multispecies virtual population analysis (MSVPA) is an approach to quantifying predator prey interactions and estimating the rates of predation mortality for exploited fish populations. Here, an extended MSVPA (MSVPA-X) is presented as an alternative to existing MSVPA approaches. Notably, MSVPA-X uses index-tuned VPA methods, applies a more flexible feeding model, and includes an alternative functional feeding response. The MSVPA-X model is applied to a western Atlantic fish community, focusing on Atlantic menhaden and its major fish predators, and a sensitivity analysis ...


Subtle Biological Responses To Increased Co2 Concentrations By Phaeocystis Globosa Scherffel, A Harmful Algal Bloom Species, Y Wang, WO Smith, XD Wang, SS Li 2010 Virginia Institute of Marine Science

Subtle Biological Responses To Increased Co2 Concentrations By Phaeocystis Globosa Scherffel, A Harmful Algal Bloom Species, Y Wang, Wo Smith, Xd Wang, Ss Li

VIMS Articles

Recent investigations into the role of carbon dioxide on phytoplankton growth and composition have clearly shown differential effects among species and assemblages, suggesting that increases in oceanic CO2 may play a critical role in structuring lower trophic levels of marine systems in the future. Furthermore, alarming increases in the occurrence of harmful algal blooms (HABs) in coastal waters have been observed, and while not uniform among systems, appear in some manner to be linked to human impacts (eutrophication) on coastal systems. Models of HABs are in their infancy and do not at present include sophisticated biological effects or their environmental ...


Production Of Dissolved Organic Matter And Inorganic Nutrients By Gelatinous Zooplankton In The York River Estuary, Chesapeake Bay, RH Condon, DK Steinberg, DA Bronk 2010 Virginia Institute of Marine Science

Production Of Dissolved Organic Matter And Inorganic Nutrients By Gelatinous Zooplankton In The York River Estuary, Chesapeake Bay, Rh Condon, Dk Steinberg, Da Bronk

VIMS Articles

Large "blooms" of ctenophores (Mnemiopsis leidyi) and scyphomedusae (Chrysaora quinquecirrha) occur throughout the York River, a sub-estuary of Chesapeake Bay. These gelatinous zooplankton blooms can influence carbon (C) and nutrient cycling through excretion of dissolved organic matter (DOM), and inorganic nitrogen (N) and phosphorus (P). We measured dissolved organic carbon, nitrogen and phosphorus (DOC, DON and DOP), ammonium (NH(4)(+)) and phosphate (PO(4)(3-)) released by M. leidyi and C. quinquecirrha in the laboratory, and estimated their contribution to in situ DOC and inorganic pools. Both species released high amounts of DOC compared with DON and DOP. DOM released ...


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