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Size-Structured Competition And Predation In Red-Eyed Treefrog Tadpoles, Christopher Asquith 2010 Virginia Commonwealth University

Size-Structured Competition And Predation In Red-Eyed Treefrog Tadpoles, Christopher Asquith

Theses and Dissertations

Body size is important in determining the outcome of competition and predator-prey interactions. Size structure of a population (i.e. relative proportion of large and small conspecifics) may be particularly important in organisms with prolonged breeding periods and rapid growth where populations may have multiple cohorts at different stages of development competing for one resource. Both the consumptive and nonconsumptive effects of predators can also be size-dependent and can alter competitive interactions. Here we study the importance of size structure in the Neotropical leaf-breeding tree frog, Agalychnis callidryas. This species is a prolonged breeder such that multiple overlapping cohorts of ...


Effects Of Light And Nutrient Supply On Stable Isotope Composition And Fractionation In Nitrogen-Limited Seagrass Beds, Rebecca Jane Bernard 2010 Florida International University

Effects Of Light And Nutrient Supply On Stable Isotope Composition And Fractionation In Nitrogen-Limited Seagrass Beds, Rebecca Jane Bernard

FIU Electronic Theses and Dissertations

This experiment investigated causes of seasonality of δ15N and δ13C values in Thalassia testudinum leaf tissue by manipulating plant demand and nutrient supply in situ for 13 months. I clearly demonstrated that seagrass elemental content, stable C and N isotopic content, morphology and the concentration of NH4+ seagrass porewaters directly respond to manipulations of resources and also by the plant demand for nutrients to support growth. Isotopic values displayed marked seasonality with heavier values found in summer (δ15N=5.0% δ13C=-5.7%o) and lighter values in winter (δ15 ...


Cull Sow Feeding Management, Robert F. Fitzgerald, Kenneth J. Stalder, Joel M. DeRouchey 2010 Iowa State University

Cull Sow Feeding Management, Robert F. Fitzgerald, Kenneth J. Stalder, Joel M. Derouchey

Animal Science White Papers, Technical Reports, & Fact Sheets

The decision to cull a sow from the breeding herd typically occurs after weaning due to poor lactation performance, lameness or if she fails to breed or conceive. Once the decision to cull a sow from the breeding herd has been made, a producer must decide to either immediately market the sow or to increase marketable body weight by feeding her for a period of time. The decision to feed cull sows to add additional body weight is not a simple decision. Many factors such as current cull sow market prices, available housing space, feed cost, and health of the ...


The Beasts In Our Brain, Neil Greenberg 2010 University of Tennessee - Knoxville

The Beasts In Our Brain, Neil Greenberg

Neil Greenberg

In the neuropsychology of art, we must remember that the Brain of Man has not abandoned its ancient animal foundations, it has built upon them . . . . But it has also reconstructed them as the shifting earth beneath dictates . . . . We have done the best possible in the landscape in which we have found ourselves with the raw materials we have inherited." --(Greenberg, Prolegomena to a Study of Mind, 1973, ch. 42)


Seasonal Body Temperature Fluctuations And Energetic Strategies In Free-Ranging Eastern Woodchucks, Carmen M. Salsbury 2010 Butler University

Seasonal Body Temperature Fluctuations And Energetic Strategies In Free-Ranging Eastern Woodchucks, Carmen M. Salsbury

Carmen M. Salsbury

During a 2-year period, radiotelemetry was used to continuously monitor body temperature ( T b) of free-ranging woodchucks (Marmota monax) in southeastern Pennsylvania. Hibernation was preceded by daily T b fluctuations ("test drops") of 2-4°C. During hibernation, woodchucks exhibited the characteristic pattern of torpor bouts. Time of arousals occurred randomly, but onset of torpor occurred predominantly between 1800 and 0000 h. Males had shorter hibernation periods (mean of 104.8 days) than did females (121.8 days). Males had shorter torpor bouts, but euthermic bouts were the same length as in females. Males also maintained higher T b during torpor ...


Non-Invasive Genetic Sampling Of Faecal Material And Hair From The Grey-Headed Flying-Fox (Pteropus Poliocephalus), Heather J. Baldwin, Stephen J. Hoggard, Stephanie T. Snoyman, Adam J. Snow, Culum Brown 2010 Macquarie University

Non-Invasive Genetic Sampling Of Faecal Material And Hair From The Grey-Headed Flying-Fox (Pteropus Poliocephalus), Heather J. Baldwin, Stephen J. Hoggard, Stephanie T. Snoyman, Adam J. Snow, Culum Brown

SCI

Remote-sampling DNA from animals offers obvious benefits for species that are difficult to sample directly and is less disruptive for species of conservation concern. Here we report the results of a pilot study investigating non-invasive DNA sampling of the grey-headed flying-fox (Pteropus poliocephalus), a threatened species that is restricted to the east coast of Australia. We successfully extracted DNA from fresh scats and hair, each of which was of sufficient quality for amplifying mitochondrial DNA markers and microsatellites. A single-locus multitube approach was used to investigate amplification success and genotyping reliability. Faecal samples yielded a higher proportion of successful amplifications ...


Computational Design And Elaboration Of A De Novo Heterotetrameric Α-Helical Protein That Selectively Binds An Emissive Abiological (Porphinato)Zinc Chromophore, H Christopher Fry, Andreas Lehmann, Jeffery G. Saven, William F. DeGrado, Michael J. Therien 2010 University of Pennsylvania

Computational Design And Elaboration Of A De Novo Heterotetrameric Α-Helical Protein That Selectively Binds An Emissive Abiological (Porphinato)Zinc Chromophore, H Christopher Fry, Andreas Lehmann, Jeffery G. Saven, William F. Degrado, Michael J. Therien

Departmental Papers (Chemistry)

The first example of a computationally de novo designed protein that binds an emissive abiological chromophore is presented, in which a sophisticated level of cofactor discrimination is pre-engineered. This heterotetrameric, C(2)-symmetric bundle, A(His):B(Thr), uniquely binds (5,15-di[(4-carboxymethyleneoxy)phenyl]porphinato)zinc [(DPP)Zn] via histidine coordination and complementary noncovalent interactions. The A(2)B(2) heterotetrameric protein reflects ligand-directed elements of both positive and negative design, including hydrogen bonds to second-shell ligands. Experimental support for the appropriate formulation of [(DPP)Zn:A(His):B(Thr)](2) is provided by UV/visible and circular dichroism spectroscopies ...


Processes Influencing Seasonal Hypoxia In The Northern California Current System, Thomas Connolly, Barbara Hickey, S. Geier, William Cochlan 2010 University of Washington

Processes Influencing Seasonal Hypoxia In The Northern California Current System, Thomas Connolly, Barbara Hickey, S. Geier, William Cochlan

Thomas P. Connolly

This paper delineates the role of physical and biological processes contributing to hypoxia, dissolved oxygen (DO) < 1.4 mL/L, over the continental shelf of Washington State in the northern portion of the California Current System. In the historical record (1950–1986), during the summer upwelling season, hypoxia is more prevalent and severe off Washington than further south off northern Oregon. Recent data (2003–2005) show that hypoxia over the Washington shelf occurred at levels previously observed in the historical data. The year 2006 was an exception, with hypoxia covering ∼5000 km2 of the Washington continental shelf and DO concentrations ...


Transcriptional Regulation Of Vegfa By Unfolded Protein Response Signaling Pathway, Rajarshi Ghosh 2010 University of Massachusetts Medical School

Transcriptional Regulation Of Vegfa By Unfolded Protein Response Signaling Pathway, Rajarshi Ghosh

GSBS Dissertations and Theses

The endoplasmic reticulum is the primary organelle in the cell which has the responsibility of properly folding proteins belonging to the secretory pathway. Secretory proteins are essential for a variety of functions within the body like metabolism, growth and survival. Hence, proper folding of the proteins in the ER is absolutely essential to maintain cellular and body function. The environment of the ER is substantially different from that of the cytoplasm and is primed essentially to provide the optimum conditions to fold newly synthesized polypeptides following translation by the ribosomes in the cytoplasm and on the surface of the ER ...


Permutation-Based Pathway Testing Using The Super Learner Algorithm, Paul Chaffee, Alan E. Hubbard, Mark L. van der Laan 2010 Division of Biostatistics, UC Berkeley

Permutation-Based Pathway Testing Using The Super Learner Algorithm, Paul Chaffee, Alan E. Hubbard, Mark L. Van Der Laan

U.C. Berkeley Division of Biostatistics Working Paper Series

Many diseases and other important phenotypic outcomes are the result of a combination of factors. For example, expression levels of genes have been used as input to various statistical methods for predicting phenotypic outcomes. One particular popular variety is the so-called gene set enrichment analysis (GSEA). This paper discusses an augmentation to an existing strategy to estimate the significance of an associations between a disease outcome and a predetermined combination of biological factors, based on a specific data adaptive regression method (the "Super Learner," van der Laan et al., 2007). The procedure uses an aggressive search procedure, potentially resulting in ...


Sweetened Beverage Consumption And Its Contributing Factors Among School-Aged Children–A Multilevel Analysis, Meizi He, Leonard Piché, Danielle Battram, Isabelle Giroux, Charlene Beynon, Jacqline Swans, Rohna Hanning 2010 University of Texas at San Antonio

Sweetened Beverage Consumption And Its Contributing Factors Among School-Aged Children–A Multilevel Analysis, Meizi He, Leonard Piché, Danielle Battram, Isabelle Giroux, Charlene Beynon, Jacqline Swans, Rohna Hanning

Leonard Piché

Excessive consumption of sweetened beverages by children and youth has become an issue of great concern among health professionals and health policy makers in the U.S. and Canada. Over-consumption of sweetened beverages can have negative effects on children's nutrient profile and may increase their risk of obesity. Reducing children's sweetened beverage consumption offers an opportunity to decrease unnecessary energy intake and prevent excess weight gain.


Population Genetic Structure In Nolina Brittoniana (Agavaceae), A Plant Endemic To The Central Ridges Of Florida, Rebecca W. Dolan, Rebecca Yahr, Eric S. Menges 2010 Butler University

Population Genetic Structure In Nolina Brittoniana (Agavaceae), A Plant Endemic To The Central Ridges Of Florida, Rebecca W. Dolan, Rebecca Yahr, Eric S. Menges

Rebecca W. Dolan

Nolina brittoniana is endemic to the central ridges of peninsular Florida. Its scrub and sandhill habitats have suffered extensive anthropogenic modification. Analysis of isozymes from populations throughout its range revealed less genetic variation than generally reported for endemic plants. Populations were well differentiated, with significant clines in allele frequency along the north-south axis of distribution. Pair-wise F-statistics calculated at four levels of population geographic substructure revealed that current and inferred historical habitat patches had similar genetic structure. We found no evidence of recent bottlenecks or changes in genetic structure due to habitat loss and fragmentation, consistent with populations having always ...


Antioxidant Capacity And Polyphenol Content Of Brown Seaweeds After Heat Processing, Gaurav Rajauria, Shilpi Gupta, Nissreen Abu-ghannam, Amit Jaiswal 2010 Dublin Institute of Technology

Antioxidant Capacity And Polyphenol Content Of Brown Seaweeds After Heat Processing, Gaurav Rajauria, Shilpi Gupta, Nissreen Abu-Ghannam, Amit Jaiswal

Articles

Seaweeds or marine macroalgae are renewable living resources which are also used as food, feed and fertilizer in many parts of the world. They are able to produce a great variety of secondary metabolites characterized by a broad spectrum of biological behavior such as antibacterial and antioxidant activities. The effect of heat treatment was investigated on the level of bioactive compounds and changes in the overall antioxidant capacity of edible Irish brown seaweeds namely Himanthalia elongata, Laminaria saccharina and Laminaria digitata. In order to make the seaweeds safe and edible, they were heated at 85, 95, 100, 110 and 121 ...


Information About Corn Nematodes And Scn Available Online From Isu Crop Adviser Institute, Gregory L. Tylka 2010 Iowa State University

Information About Corn Nematodes And Scn Available Online From Isu Crop Adviser Institute, Gregory L. Tylka

Integrated Crop Management News

A new source of information about the biology and management of corn nematodes is now available free online from Iowa State University. It’s a training module from the ISU Crop Adviser Institute. Topics discussed in the module include:

  • the different species of nematodes that can parasitize corn
  • review of the basic biology of corn nematodes
  • symptoms of nematode damage to corn
  • how to determine if a corn field has nematode damage
  • current management options for corn nematodes
  • the new cyst nematode discovered on corn in 2007


The Perceptions, Attitudes And Practices Of Registered Dietitians Regarding Functional Foods, Amanda Berhaupt 2010 Florida International University

The Perceptions, Attitudes And Practices Of Registered Dietitians Regarding Functional Foods, Amanda Berhaupt

FIU Electronic Theses and Dissertations

The term “functional food” (FF) has a variety of definitions resulting in term ambiguity. It is unclear Registered Dietitians’ (RDs) understanding and practices about FF. A descriptive, cross-sectional study investigated RDs’ perceptions, attitudes and practices regarding FF. A national random sample (n=1800) of RDs was mailed a FF questionnaire, 385 (22%) responded. Given five definitions from food-nutrition authorities, the majority of RDs did not agree on a definition, although three-fourths (n=292, 75.8%) perceived fortified foods as FF. Registered Dietitians agreed FF could improve health (n=266, 69.1%), prevent disease (n=282, 73.2%) and treat clientele ...


Biologia Subterrânea Em Zonas Cársicas Portuguesas, Ana Sofia P.S. Reboleira, Pedro Oromí, Fernando Gonçalves 2010 University of Aveiro

Biologia Subterrânea Em Zonas Cársicas Portuguesas, Ana Sofia P.S. Reboleira, Pedro Oromí, Fernando Gonçalves

Ana Sofia P.S. Reboleira

O domínio subterrâneo, composto por uma vasta rede de cavidades e fissuras, alberga um ecossistema peculiar, rico em microendemismos e espécies que exibem adaptações morfofisiológicas à vida em profundidade. Os ecossistemas subterrâneos estão sujeitos a variadas pressões ambientais decorrentes da utilização do solo à superfície. A sensibilidade ecológica que caracteriza as regiões cársicas, acrescida de um conhecimento científico incipiente, traduz-se na irreversível degradação destes ecossistemas. A extensão dos habitats subterrâneos é bastante alargada, contudo a sua Biologia é, em boa medida, desconhecida. O conhecimento actual da Biologia subterrânea das regiões cársicas baseia-se, sobretudo, em trabalhos de taxonomia clássica realizados no ...


Claytonia Virginica L., Gordon C. Tucker 2010 Eastern Illinois University

Claytonia Virginica L., Gordon C. Tucker

Specimens by Name

No abstract provided.


In A Like-Kind Exchange, What If A Qualified Intermediary Fails?, Neil E. Harl 2010 Iowa State University

In A Like-Kind Exchange, What If A Qualified Intermediary Fails?, Neil E. Harl

Agricultural Law Digest

The economic and financial trauma of roughly the past 30 months has taken a toll on many financial institutions and organizations, including qualified intermediaries1 utilized in like-kind exchanges.2 The failure of qualified intermediaries or the inability to perform has caused immense concern among taxpayers and tax practitioners alike.


Cases, Regulations, And Statutes, Robert P. Achenbach Jr 2010 Iowa State University

Cases, Regulations, And Statutes, Robert P. Achenbach Jr

Agricultural Law Digest

No abstract provided.


Metagenomes From High-Temperature Chemotrophic Systems Reveal Geochemical Controls On Microbial Community Structure And Function, William P. Inskeep, Douglas B. Rusch, Zackary J. Jay, Markus J. Herrgard, Mark A. Kozubal, Toby H. Richardson, Richard E. Macur, Natsuko Hamamura, Ryan deM. Jennings, Bruce W. Fouke, Anna-Louise Reysenbach, Frank Roberto, Mark Young, Ariel Schwartz, Eric S. Boyd, Jonathan H. Badger, Eric J. Mathur, Alice C. Ortmann, Mary Bateson, Gill Geesey 2010 Montana State University - Bozeman

Metagenomes From High-Temperature Chemotrophic Systems Reveal Geochemical Controls On Microbial Community Structure And Function, William P. Inskeep, Douglas B. Rusch, Zackary J. Jay, Markus J. Herrgard, Mark A. Kozubal, Toby H. Richardson, Richard E. Macur, Natsuko Hamamura, Ryan Dem. Jennings, Bruce W. Fouke, Anna-Louise Reysenbach, Frank Roberto, Mark Young, Ariel Schwartz, Eric S. Boyd, Jonathan H. Badger, Eric J. Mathur, Alice C. Ortmann, Mary Bateson, Gill Geesey

Biology Faculty Publications and Presentations

The Yellowstone caldera contains the most numerous and diverse geothermal systems on Earth, yielding an extensive array of unique high-temperature environments that host a variety of deeply-rooted and understudied Archaea, Bacteria and Eukarya. The combination of extreme temperature and chemical conditions encountered in geothermal environments often results in considerably less microbial diversity than other terrestrial habitats and offers a tremendous opportunity for studying the structure and function of indigenous microbial communities and for establishing linkages between putative metabolisms and element cycling. Metagenome sequence (14-15,000 Sanger reads per site) was obtained for five hightemperature (>65°C) chemotrophic microbial communities sampled ...


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