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Full-Text Articles in Life Sciences

Disturbance Interactions In Subalpine Forests, Their Impacts On Forest Resilience, Carbon, And Future Carbon Storage Under A Variety Of Management And Climate Change Scenarios, Brian Buma Jan 2913

Disturbance Interactions In Subalpine Forests, Their Impacts On Forest Resilience, Carbon, And Future Carbon Storage Under A Variety Of Management And Climate Change Scenarios, Brian Buma

Ecology & Evolutionary Biology Graduate Theses & Dissertations

Forest disturbances are inevitable, and recovery from those disturbances (termed resilience) is required for the persistence of forests through time. Extraordinarily severe or compounding multiple disturbances may, however, exceed that resilience and shift the ecosystems into alternate regimes with potentially large implications for ecosystem structure and functioning. A compound disturbance event (wind, logging, and fire) in a Colorado subalpine forest was studied for the impact of the multiple disturbance events on disturbance characteristics, tree regeneration, and carbon stocks, an important ecosystem service provided by many forests. The regeneration was also grown using the Forest Vegetation Simulator to simulate the effects ...


Recent Decline Of Lowland Populations Of The Western Gray Squirrel In The Los Angeles Area Of Southern California, Daniel S. Cooper, Alan Muchlinski Jul 2105

Recent Decline Of Lowland Populations Of The Western Gray Squirrel In The Los Angeles Area Of Southern California, Daniel S. Cooper, Alan Muchlinski

Bulletin of the Southern California Academy of Sciences

We provide an overview of the distribution of lowland and otherwise isolated populations of the western gray squirrel (Sciurus griseus) in the Los Angeles area of southern California, an area that has experienced a recent and ongoing invasion by the non-native eastern fox squirrel (Sciurus niger), an urban-adapted species introduced a century ago. Away from its strongholds in the western Santa Monica Mountains, San Gabriel Mountains, and Santa Ana Mountains, the western gray squirrel is resident locally in both the Santa Susana and the Verdugo Mountains, in Griffith Park, in low hills at the eastern periphery of the San Gabriel ...


An Orange Fluorescent Protein Tagging System For Real-Time Pollen Tracking, J. Rice, R. Mundell, R. Millwood, O. Chambers, L. Abercrombie, H. Davies, C. Stewart Dec 2102

An Orange Fluorescent Protein Tagging System For Real-Time Pollen Tracking, J. Rice, R. Mundell, R. Millwood, O. Chambers, L. Abercrombie, H. Davies, C. Stewart

C. Neal Stewart Jr.

Background Monitoring gene flow could be important for future transgenic crops, such as those producing plant-made-pharmaceuticals (PMPs) in open field production. A Nicotiana hybrid (Nicotiana. tabacum × Nicotiana glauca) shows limited male fertility and could be used as a bioconfined PMP platform. Effective assessment of gene flow from these plants is augmented with methods that utilize fluorescent proteins for transgenic pollen identification. Results We report the generation of a pollen tagging system utilizing an orange fluorescent protein to monitor pollen flow and as a visual assessment of transgene zygosity of the parent plant. This system was created to generate a tagged ...


Effect Of External Energy On The Atomic, Crystalline, And Powder Characteristics Of Antimony And Bismuth Powders, Mahendra Kumar Trivedi Sep 2099

Effect Of External Energy On The Atomic, Crystalline, And Powder Characteristics Of Antimony And Bismuth Powders, Mahendra Kumar Trivedi

Mahendra Kumar Trivedi

Next to atoms and molecules the powders are the smallest state of matter available in high purities and large quantities. The effect of any external energy on the shape, morphology and structure can thus be studied with relative ease. The present investigation deals with the effect of a non-contact external energy on the powders of antimony and bismuth. The characteristics of powders treated by external energy are compared with the as received powders (control). The average particle sizes, d50 and d99, the sizes below which 99% of the particles are present showed significant increase and decrease indicating that the energy ...


Tea Induction Of Cyp6a8 Promoter In Drosophila Melanogaster, Fiona Retzer Dec 2017

Tea Induction Of Cyp6a8 Promoter In Drosophila Melanogaster, Fiona Retzer

University of Tennessee Honors Thesis Projects

No abstract provided.


Improving The Player's Recruiting Process By Using Scenario Based Analysis Methodology, Dotan I. Shvorin, Kevin M. Taaffe Jan 2017

Improving The Player's Recruiting Process By Using Scenario Based Analysis Methodology, Dotan I. Shvorin, Kevin M. Taaffe

Dotan Shvorin

High performance physical characteristics can be found today in most of the potential recruitsfor any athletic program and it has become increasingly dificult to select the right candidatebased solely on these characteristics. As a result there is a growing need for a recruiter to evaluatethe decision-making capability of a player in order to understand the mind of the player inaddition to the player physical assessment. We employ scenario-based analysis to evaluate suchdecision-making capabilities while enabling any recruiting to customize the potential candidateevaluation, based on the specific program's needs. The proposed method provides a platformfor decision making evaluation within a ...


Effects Of Novel Fragment-Warhead Adducts In Situ And In Vitro With Glutaredoxin Orthologs., Andrew J. Caras Jan 2017

Effects Of Novel Fragment-Warhead Adducts In Situ And In Vitro With Glutaredoxin Orthologs., Andrew J. Caras

Honors Research Projects

Fragment-based drug design (FBDD) is a method of pharmaceutical research involving characterization of small “fragment” molecule interactions with a target protein. These fragments are optimized with the addition of a nucleophilic “warhead” moiety. Several novel fragment-warhead adducts have been synthesized in house by group member Ram Khattri Ph.D. The experiment investigates reactivity of these adducts with glutaredoxin protein (Grx) orthologs from Homo sapiens, Pseudomonas aeruginosa and Brucella melitensis. Three novel fragment-warhead adducts have been identified to cause weakly bacteriostatic and bacteriocidal effects, most with minimum inhibitory concentration values near 1.28 mg/mL. Discussed herein are molecular effects of ...


Molecular Biology Of A Surface-Exposed Protein Family Of Bartonella Bacilliformis, Hannah Fay Jan 2017

Molecular Biology Of A Surface-Exposed Protein Family Of Bartonella Bacilliformis, Hannah Fay

Undergraduate Theses and Professional Papers

Bartonella bacilliformis is a gram negative alpha-proteobacterium native to the Andes of South America. Bartonella causes Carrion’s disease, a potentially life threatening disease transmitted by the sand fly. It has a mortality rate of 88% when untreated and 10% when treated. Diagnostics and control measures for the disease are underdeveloped and no vaccine is available. Recent outbreaks indicate that the range of the pathogen is increasing with nearly 1.7 million people in western South America at risk. Little is known about the epidemiology and pathogenesis of B. bacilliformis. Recent research done by UC San Diego found a paralogous ...


Supplemental Data, Russell J. Ingram, Foster Levy, Cindy L. Barrett, James T. Donaldson Jan 2017

Supplemental Data, Russell J. Ingram, Foster Levy, Cindy L. Barrett, James T. Donaldson

ETSU Faculty Works

No abstract provided.


The Role Of Gpx-8 In Dna Repair Of C. Elegans, Grant T. Read Jan 2017

The Role Of Gpx-8 In Dna Repair Of C. Elegans, Grant T. Read

University of Iowa Honors Theses

Double-stranded breaks are necessary for the resolution of crossovers during the heterotypic cell division of meiosis I. Failure to repair these DSBs can lead to programmed cell death, or apoptosis. Caenorhabditis elegans, a member of the phylum Nematoda, is a model organism for the study of meiosis due to the temporal-spatial pattern of its gonad. gpx-8, homologous to human gpx-4, codes for a member of the glutathione peroxidase family, a group of proteins involved in the detoxification of peroxides. This project examined the effects of a homozygous deletion of the gpx-8 gene on the C. elegans germ line. The primary ...


J. C. Penney: The Man, The Store And American Agriculture (Under Contract), David Kruger Dec 2016

J. C. Penney: The Man, The Store And American Agriculture (Under Contract), David Kruger

David Delbert Kruger

No abstract provided.


Visual Methods For Collaborative Food System Work, K. Valentine Cadieux, Charles Levkoe, P. Mount, D. Szanto Dec 2016

Visual Methods For Collaborative Food System Work, K. Valentine Cadieux, Charles Levkoe, P. Mount, D. Szanto

K. Valentine Cadieux

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Morphological And Molecular Analysis Using Rapd In Biofield Treated Sponge And Bitter Gourd, Mahendra Trivedi Dec 2016

Morphological And Molecular Analysis Using Rapd In Biofield Treated Sponge And Bitter Gourd, Mahendra Trivedi

Mahendra Kumar Trivedi

Plants are known to have sense and can respond to touch, electric and magnetic field. The present study was designed on the sponge gourd (Luffa cylindrica) and bitter gourd (Momordica charantia) seeds with respect to biofield energy treatment. The seeds of each crop were divided into two groups, one was kept control, while the other group was subjected to Mr. Trivedi’ biofield energy treatment. The variabilities in growth contributing parameters were studied and compared with their control. To study the genetic variability after biofield energy treatment, both the seeds were analyzed for DNA fingerprinting using RAPD method. After germination, the ...


Morphological And Molecular Analysis Using Rapd In Biofield Treated Sponge And Bitter Gourd, Mahendra Kumar Trivedi Dec 2016

Morphological And Molecular Analysis Using Rapd In Biofield Treated Sponge And Bitter Gourd, Mahendra Kumar Trivedi

Mahendra Kumar Trivedi

Plants are known to have sense and can respond to touch, electric and magnetic field. The present study was designed on the sponge gourd (Luffa cylindrica) and bitter gourd (Momordica charantia) seeds with respect to biofield energy treatment. The seeds of each crop were divided into two groups, one was kept control, while the other group was subjected to Mr. Trivedi’ biofield energy treatment. The variabilities in growth contributing parameters were studied and compared with their control. To study the genetic variability after biofield energy treatment, both the seeds were analyzed for DNA fingerprinting using RAPD method. After germination, the ...


Environmental Res. Bernard Singleton 2016 .Pdf, Joy Semien Dec 2016

Environmental Res. Bernard Singleton 2016 .Pdf, Joy Semien

Joy Semien

The Deepwater Horizon (DWH) oil spill in the Gulf of Mexico was the largest maritime oil spill in history
resulting in the accumulation of genotoxic substances in the air, soil, and water. This has potential far-
reaching health impacts on cleanup field workers and on the populations living in the contaminated
coastal areas. We have employed portable airborne particulate matter samplers (SKC Biosampler Im-
pinger) and a genetically engineered bacterial reporter system (umu-ChromoTest from EBPI) to de-
termine levels of genotoxicity of air samples collected from highly contaminated areas of coastal
Louisiana including Grand Isle, Port Fourchon, and Elmer's ...


Netrin-3 Peptide (C-19) Is A Chemorepellent And A Growth Inhibitor In Tetrahymena Thermophila, Matthew S. Merical, Kenneth W. Ward, Lois Parks, Heather G. Kuruvilla Dec 2016

Netrin-3 Peptide (C-19) Is A Chemorepellent And A Growth Inhibitor In Tetrahymena Thermophila, Matthew S. Merical, Kenneth W. Ward, Lois Parks, Heather G. Kuruvilla

Science and Mathematics Faculty Presentations

The netrins are a family of signaling proteins expressed throughout the animal kingdom. Netrins play important roles in developmental processes such as axonal guidance and angiogenesis. Netrin-1, for example, can act as either a chemoattractant or a chemorepellent for axonal growth cones depending upon the concentration of the protein as well as the cell type. Netrin-1 acts as a growth factor in some cell types and is expressed by some tumor cells. Netrin-3 appears to share some signaling apparatus with netrin-1, but is less widely expressed, and its physiological roles are much less understood.

Tetrahymena thermophila are free-living, eukaryotic, ciliated ...


Consumer Willingness To Pay For Genetically Modified Food Labels In A Market With Diverse Information: Evidence From Experimental Auctions, Wallace E. Huffman, Jason F. Shogren, Matthew Rousu, Abebayehu Tegene Dec 2016

Consumer Willingness To Pay For Genetically Modified Food Labels In A Market With Diverse Information: Evidence From Experimental Auctions, Wallace E. Huffman, Jason F. Shogren, Matthew Rousu, Abebayehu Tegene

Wallace Huffman

With the continuing controversy over genetically modified (GM) foods, some groups advocate mandatory labeling of these products, while other groups oppose labeling. An important issue is how GM labels affect consumers' willingness to pay for these food products in the market. Using a statistically based economics experiment with adult consumers as subjects, we examine how willingness to pay changes for three food products - vegetable oil, tortilla chips, and potatoes - when GM labels are intro- duced. Participants in the experiments discounted GM-labeled foods by approximately 14% relative to their standard-labeled counterparts. The evidence also showed that sequencing of food labels affects ...


Consumer Demand For Potato Products And Willingness-To-Pay For Low-Acrylamide, Sulfite-Free Fresh Potatoes And Dices: Evidence From Lab Auctions, Katie Lacy, Wallace E. Huffman Dec 2016

Consumer Demand For Potato Products And Willingness-To-Pay For Low-Acrylamide, Sulfite-Free Fresh Potatoes And Dices: Evidence From Lab Auctions, Katie Lacy, Wallace E. Huffman

Wallace Huffman

We assess consumer demand for traditional fresh potatoes and processed potato products and willingness to pay for new experimental low-acrylamide and sulfite-free potato products. Demand for fresh potatoes, potato chips, and fries is unaffected by household income or education, but demand for chips and fries is affected by consumer age and exercise habits. Subjects display increased willingness to pay for new potato products after receiving a private company perspective about the technology and risks associated with exposure to acrylamide, a carcinogen, in fried conventional potatoes and a new product, potato dices. We find that consumers are willing to pay for ...


Nonmotorized Recreation And Motorized Recreation In Shrub-Steppe Habitats Affects Behavior And Reproduction Of Golden Eagles (Aquila Chrysaetos), Robert J. Spaul, Julie A. Heath Dec 2016

Nonmotorized Recreation And Motorized Recreation In Shrub-Steppe Habitats Affects Behavior And Reproduction Of Golden Eagles (Aquila Chrysaetos), Robert J. Spaul, Julie A. Heath

Julie Heath

Different forms of outdoor recreation have different spatiotemporal activity patterns that may have interactive or cumulative effects on wildlife through human disturbance, physical habitat change, or both. In western North America, shrub-steppe habitats near urban areas are popular sites for motorized recreation and nonmotorized recreation and can provide important habitat for protected species, including golden eagles. Our objective was to determine whether recreation use (i.e., number of recreationists) or recreation features (e.g., trails or campsites) predicted golden eagle territory occupancy, egg-laying, or the probability a breeding attempt resulted in ≥1 offspring (nest survival). We monitored egg-laying, hatching and ...


Winners And Losers: Formula Versus Competitive Funding Of Agricultural Research, Wallace E. Huffman, George Norton, Greg Traxler, George Frisvold, Jeremy Foltz Dec 2016

Winners And Losers: Formula Versus Competitive Funding Of Agricultural Research, Wallace E. Huffman, George Norton, Greg Traxler, George Frisvold, Jeremy Foltz

Wallace Huffman

State Agricultural Experiment Stations (SAESs) were established with federal formula funding by the Hatch Act of 1887. In 1955, the Hatch Act was amended and a number of subsequent formula funding programs were consolidated under the USDA Cooperative States Research Service (CSRS), which today is known as the Cooperative Research, Education and Extension Service (CSREES). Currently, all of the Hatch funds and a small amount of other formula funds go to SAESs. In 1977, CSRS established its first competitive research grant program. However, this program remained quite small until 1990, when it was re-named the National Research Initiative (NRI) Competitive ...


The Value Of Verifiable Information In A Controversial Market: Evidence From Lab Auctions Of Genetically Modified Food, Matthew Rousu, Wallace Huffman, Jason F. Shogren, Abebayehu Tegene Dec 2016

The Value Of Verifiable Information In A Controversial Market: Evidence From Lab Auctions Of Genetically Modified Food, Matthew Rousu, Wallace Huffman, Jason F. Shogren, Abebayehu Tegene

Wallace Huffman

Two interested parties dominate the current debate on genetically modified (GM) foods: environmental groups and agribusiness companies. For the average consumer to arrive at an informed decision on these new foods, they must rely on information from interested parties. Unfortunately, information from interested parties does not provide an accurate picture of the benefits and risks of new products. This paper examines the effects of information on consumers’ demand for new food products, GM-foods, in an environment where information from one or more interested parties is provided. We design and conduct laboratory auction experiments using randomly chosen adult consumers from two ...


Who Do Consumers Trust For Information: The Case Of Genetically Modified Foods?, Wallace Huffman, Matthew Rousu, Jason Shogren, Abebayehu Tegene Dec 2016

Who Do Consumers Trust For Information: The Case Of Genetically Modified Foods?, Wallace Huffman, Matthew Rousu, Jason Shogren, Abebayehu Tegene

Wallace Huffman

To be effective, groups that disseminate information need trust. When different groups provide conflicting information on a new product or process like genetically modified (GM) foods, we hypothesize that consumers place different levels of trust in the sources and trust is related to their income, personal and social capital, and prior beliefs. A random sample of adults was asked to state their preferences for sources they would trust to provide verifiable (i.e., objective) information on genetic modification. Their responses were grouped into six categories, and a multinominal logit model used to explain relative trust in information sources. Relative trust ...


Who Do Consumers Trust For Information: The Case Of Genetically Modified Foods?, Wallace E. Huffman, Matthew Rousu, Jason F. Shogren, Abebayehu Tegene Dec 2016

Who Do Consumers Trust For Information: The Case Of Genetically Modified Foods?, Wallace E. Huffman, Matthew Rousu, Jason F. Shogren, Abebayehu Tegene

Wallace Huffman

During the twentieth century, research and development (R&D) has produced a steady stream of inventions and new consumer goods, many of which have been adopted and proven to be the source of a rising standard of living (Boskin et al.). The introduction of new goods, however, creates a disequilibrium (Hausman), which in turn creates a demand by economic agents for objective information to assist in making decisions on adoption and use (Schultz).1 The consumer's challenge is to sort through the various, competing and sometimes conflicting, sources of information.


The Effects Of Prior Beliefs And Learning On Consumers’ Acceptance Of Genetically Modified Foods, Wallace E. Huffman, Matthew Rousu, Jason F. Shogren, Abebayehu Tegene Dec 2016

The Effects Of Prior Beliefs And Learning On Consumers’ Acceptance Of Genetically Modified Foods, Wallace E. Huffman, Matthew Rousu, Jason F. Shogren, Abebayehu Tegene

Wallace Huffman

New food products using genetically modified crops appeared in U.S. supermarkets starting in 1996, and consumers’ perceived some risks. This paper examines the role of consumers prior beliefs about genetic modification and of diverse, new information on their willingness to pay for foods that might be genetically modified. We use data from economics experiments and show that participants who had informed prior beliefs discounted GM-labeled food products more highly than those who had uninformed prior beliefs. Uninformed participants were especially susceptible to information from interested and third parties. In contrast, informed participants were generally not affected significantly by new ...


Implications Of Agency Theory For Optimal Land Tenure Contracts, Wallace E. Huffman, Richard E. Just Dec 2016

Implications Of Agency Theory For Optimal Land Tenure Contracts, Wallace E. Huffman, Richard E. Just

Wallace Huffman

For more than 2 centuries, economists have been interested in agricultural contracts, especially landowner-tenant contracts. The early work by Marshall (1890) argued that share tenancy was inefficient relative to owner cultivation and should not be expected to persist when other arrangements are available. Later D. Gale Johnson (1950) and Cheung (1969) argued that, if landowners can costlessly monitor and enforce tenants’ effort, then share tenancy can compete effectively with owner cultivation or cash rental. Subsequently, Stiglitz (1974) and Newberry and Stiglitz (1979) introduced principal-agent models in the more realistic case where monitoring is costly to study optimal landowner-tenant risk sharing ...


New Econometric Evidence On Agricultural Total Factor Productivity Determinants: Impact Of Funding Sources, Wallace Huffman, Robert E. Evenson Dec 2016

New Econometric Evidence On Agricultural Total Factor Productivity Determinants: Impact Of Funding Sources, Wallace Huffman, Robert E. Evenson

Wallace Huffman

This paper examines the impact of public and private agricultural research and extension on agricultural total factor productivity at the state level. We test the hypothesis that the composition of agricultural experiment station funding—share of funding from impact of federal competitive grants and contracts and from federal formula and state government appropriations affects the productivity of public agricultural research using data for the 48 contiguous states over 19701999. Our results show not only that sources of funding matter, but that an increase in federal competitive grant funding at the expense of federal formula funding would lower the productivity of ...


Modernizing Agriculture: A Continuing Process, Wallace E. Huffman Dec 2016

Modernizing Agriculture: A Continuing Process, Wallace E. Huffman

Wallace Huffman

Agriculture in the united states has undergone dramatic technological and social-economic structural change during the past century. Theodore W. Schultz was the first to emphasize the role of science-based technological change as a key force for causing agriculture to undergo a transition from traditional to modernizing conditions.1 It is now well established that institutionalized research, not research under taken by farmers themselves, is the key factor for producing innovations or knowledge leading to new technologies and advances in agricultural productivity under modernization. In the United States, it has taken many decades to develop the legal, political, scientific, and economic ...


Should The United States Regulate Mandatory Labeling For Genetically Modified Foods?, Wallace Huffman, Matthew Rousu, Jason F. Shogren, Abebayehu Tegene Dec 2016

Should The United States Regulate Mandatory Labeling For Genetically Modified Foods?, Wallace Huffman, Matthew Rousu, Jason F. Shogren, Abebayehu Tegene

Wallace Huffman

Public debate continues over whether the United States should regulate genetically modified (GM) foods by imposing a mandatory labeling policy. This paper develops a model that shows that a voluntary GM- labeling policy results in higher welfare than a regulated mandatory GMlabeling policy, if consumers can accurately read the signals in each market. We then develop an experiment that shows consumers behave as if they can accurately identify signals for GM foods. Our model and results support the perspective that the United States has been prudent in fending off calls for regulations demanding a mandatory GM- labeling policy.


Public R&D, Private R&D, And U.S. Agricultural Productivity Growth: Dynamic And Long-Run Relationships, Sun Ling Wang, Paul W. Heisey, Wallace E. Huffman, Keith O. Fuglie Dec 2016

Public R&D, Private R&D, And U.S. Agricultural Productivity Growth: Dynamic And Long-Run Relationships, Sun Ling Wang, Paul W. Heisey, Wallace E. Huffman, Keith O. Fuglie

Wallace Huffman

If accelerated productivity growth is to be an effective policy response for reducing greenhouse gas emissions from agriculture, the appropriate means for raising productivity needs to be addressed. Previous research has shown a close correlation between investments in public agricultural research and total factor productivity (TFP) growth in agriculture (Huffman and Evenson 2006; Alston et al. 2010; Wang et al. 2012, among the most recent, comprehensive studies). Largely neglected from this framework, however, has been the role of the private sector. Private sector spending on agricultural research and development (R&D) has grown more rapidly than public agricultural R&D ...


Effects And Value Of Verifiable Information In A Controversial Market: Evidence From Lab Auctions Of Genetically Modified Food, Matthew Rousu, Wallace Huffman, Jason F. Shogren, Abebayehu Tegene Dec 2016

Effects And Value Of Verifiable Information In A Controversial Market: Evidence From Lab Auctions Of Genetically Modified Food, Matthew Rousu, Wallace Huffman, Jason F. Shogren, Abebayehu Tegene

Wallace Huffman

Food products containing genetically modified (GM) ingredients have entered the market over the past decade. The biotech industry and environmental groups have disseminating conflicting private information about GM foods. This paper develops a unique methodology for valuing independent third-party information in such a setting and applies this method to consumers’ willingness to pay for food products that might be GM. Data are collected from real consumers in an auction market setting with randomized information and labeling treatments. The average value of third-party information per lab participant is small, but the public good value across U.S. consumers is shown to ...