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Symmetries Of The Central Vestibular System: Forming Movements For Gravity And A Three-Dimensional World, Gin McCollum, Douglas A. Hanes 2010 Portland State University

Symmetries Of The Central Vestibular System: Forming Movements For Gravity And A Three-Dimensional World, Gin Mccollum, Douglas A. Hanes

Gin McCollum

Intrinsic dynamics of the central vestibular system (CVS) appear to be at least partly determined by the symmetries of its connections. The CVS contributes to whole-body functions such as upright balance and maintenance of gaze direction. These functions coordinate disparate senses (visual, inertial, somatosensory, auditory) and body movements (leg, trunk, head/neck, eye). They are also unified by geometric conditions. Symmetry groups have been found to structure experimentally-recorded pathways of the central vestibular system. When related to geometric conditions in three-dimensional physical space, these symmetry groups make sense as a logical foundation for sensorimotor coordination.


Phase-Linking And The Perceived Motion During Off-Vertical Axis Rotation, Jan E. Holly, Scott J. Wood, Gin McCollum 2010 Portland State University

Phase-Linking And The Perceived Motion During Off-Vertical Axis Rotation, Jan E. Holly, Scott J. Wood, Gin Mccollum

Gin McCollum

Human off-vertical axis rotation (OVAR) in the dark typically produces perceived motion about a cone, the amplitude of which changes as a function of frequency. This perception is commonly attributed to the fact that both the OVAR and the conical motion have a gravity vector that rotates about the subject. Little-known, however, is that this rotating-gravity explanation for perceived conical motion is inconsistent with basic observations about self-motion perception: (a) that the perceived vertical moves toward alignment with the gravito-inertial acceleration (GIA) and (b) that perceived translation arises from perceived linear acceleration, as derived from the portion of the GIA …


Autonomous Bioluminescent Expression Of The Bacterial Luciferase Gene Cassette (Lux) In A Mammalian Cell Line, Dan M. Close, Stacey S. Patterson, Steven Ripp, Seung J. Baek, John Sanseverino, Gary S. Sayler 2010 University of Tennessee - Knoxville

Autonomous Bioluminescent Expression Of The Bacterial Luciferase Gene Cassette (Lux) In A Mammalian Cell Line, Dan M. Close, Stacey S. Patterson, Steven Ripp, Seung J. Baek, John Sanseverino, Gary S. Sayler

Steven Ripp

Background

The bacterial luciferase (lux) gene cassette consists of five genes (luxCDABE) whose protein products synergistically generate bioluminescent light signals exclusive of supplementary substrate additions or exogenous manipulations. Historically expressible only in prokaryotes, the lux operon was re-synthesized through a process of multi-bicistronic, codon-optimization to demonstrate for the first time self-directed bioluminescence emission in a mammalian HEK293 cell line in vitro and in vivo.

Methodology/Principal Findings

Autonomous in vitro light production was shown to be 12-fold greater than the observable background associated with untransfected control cells. The availability of reduced riboflavin phosphate (FMNH2) was identified as the limiting bioluminescence substrate …


Farm Focus - Spring 2010, Brian K. Whitlock, Matt Welborn, Maria Prado, Amy Plummer 2010 University of Tennessee - Knoxville

Farm Focus - Spring 2010, Brian K. Whitlock, Matt Welborn, Maria Prado, Amy Plummer

Brian K Whitlock, PhD, DVM, DACT

No abstract provided.


Quantitativepcrmethods Forrna Anddnainmarine Sediments: Maximizing Yieldwhile Overcoming Inhibition, Karen Lloyd, Barbara J. MacGregor, Andreas Teske 2010 SelectedWorks

Quantitativepcrmethods Forrna Anddnainmarine Sediments: Maximizing Yieldwhile Overcoming Inhibition, Karen Lloyd, Barbara J. Macgregor, Andreas Teske

Karen Lloyd

For accurate quantification of DNA and RNA from environmental samples, yield loss during nucleic acid purification has to be minimized. Quantitative PCR (qPCR) and reverse transcription (RT)-qPCR require a trade-off between maximizing yield and removing inhibitors. We compared DNA and RNA yield and suitability for quantitative SYBR Green PCR and RT-PCR using the UltraClean and PowerSoil extraction kits and a bead-beating protocol with phenol/chloroform extraction steps. Purification methods included silica-column-based procedures from the MoBio kits, RNeasy MinElute, WizardPlus miniprep columns, and an acrylamide gel extraction. DNA and RNA purification with WizardPlus and RNeasy, respectively, led to significant losses of nucleic …


Spatial Structure And Activity Of Sedimentary Microbial Communities Underlying A Beggiatoa Spp. Mat In A Gulf Of Mexico Hydrocarbon Seep, Karen Lloyd, Daniel B. Albert, Jennifer F. Biddle, Jeffrey P. Chanton, Oscar Pizarro, Andreas Teske 2010 SelectedWorks

Spatial Structure And Activity Of Sedimentary Microbial Communities Underlying A Beggiatoa Spp. Mat In A Gulf Of Mexico Hydrocarbon Seep, Karen Lloyd, Daniel B. Albert, Jennifer F. Biddle, Jeffrey P. Chanton, Oscar Pizarro, Andreas Teske

Karen Lloyd

Background Subsurface fluids from deep-sea hydrocarbon seeps undergo methane- and sulfur-cycling microbial transformations near the sediment surface. Hydrocarbon seep habitats are naturally patchy, with a mosaic of active seep sediments and non-seep sediments. Microbial community shifts and changing activity patterns on small spatial scales from seep to non-seep sediment remain to be examined in a comprehensive habitat study. Methodology/Principal Findings We conducted a transect of biogeochemical measurements and gene expression related to methane- and sulfur-cycling at different sediment depths across a broad Beggiatoa spp. mat at Mississippi Canyon 118 (MC118) in the Gulf of Mexico. High process rates within the …


Ethylene Receptors Function As Components Of High-Molecular-Mass Protein Complexes In Arabidopsis, Yi-Feng Chen, Zhiyong Gao, Robert J. Kerriss III, Wuyi Wang, Brad M. Binder, G. Eric Schaller 2010 University of Tennessee - Knoxville

Ethylene Receptors Function As Components Of High-Molecular-Mass Protein Complexes In Arabidopsis, Yi-Feng Chen, Zhiyong Gao, Robert J. Kerriss Iii, Wuyi Wang, Brad M. Binder, G. Eric Schaller

Brad M. Binder

The gaseous plant hormone ethylene is perceived in Arabidopsis thaliana by a five-member receptor family composed of ETR1, ERS1, ETR2, ERS2, and EIN4. Methodology/Principal Findings Gel-filtration analysis of ethylene receptors solubilized from Arabidopsis membranes demonstrates that the receptors exist as components of high-molecular-mass protein complexes. The ERS1 protein complex exhibits an ethylene-induced change in size consistent with ligand-mediated nucleation of protein-protein interactions. Deletion analysis supports the participation of multiple domains from ETR1 in formation of the protein complex, and also demonstrates that targeting to and retention of ETR1 at the endoplasmic reticulum only requires the first 147 amino acids of …


Gis @ Ut Libraries, Allison Roberts 2010 University of Tennessee - Knoxville

Gis @ Ut Libraries, Allison Roberts

Allison Roberts

Information handout/poster for GIS services at UT


Determining Rates Of Virus Production In Aquatic Systems By The Virus Reduction Approach,, M.G. Weinbauer, J.M. Rowe, Steven Wilhelm 2010 University of Tennessee, Knoxville

Determining Rates Of Virus Production In Aquatic Systems By The Virus Reduction Approach,, M.G. Weinbauer, J.M. Rowe, Steven Wilhelm

Steven Wilhelm

The reduction approach to assess virus production and the prokaryotic mortality by viral lysis stops new infection by reducing total virus abundance (and thus virus–host contacts). This allows for easy enumeration of viruses that originate from lysis of already infected cells due to the decreased abundance of free virus particles. This reoccurrence can be quantified and used to assess production and cell lysis rates. Several modifications of the method are presented and compared. The approaches have great potential for elucidating trends in virus production rates as well as for making generalized estimates of the quantitative effects of viruses on marine …


The Construction And Analysis Of Marker Gene Libraries, S.M. Short, F. Chen, Steven Wilhelm 2010 University of Tennessee, Knoxville

The Construction And Analysis Of Marker Gene Libraries, S.M. Short, F. Chen, Steven Wilhelm

Steven Wilhelm

Marker genes for viruses are typically amplified from aquatic samples to determine whether specific viruses are present in the sample, or to examine the diversity of a group of related viruses. In this chapter, we will provide an overview of common methods used to amplify, clone, sequence, and analyze virus marker genes, and will focus our discussion on viruses infecting algae, bacteria, and heterotrophic flagellates. Within this chapter, we endeavor to highlight critical aspects and components of these methods. To this end, instead of providing a detailed experimental protocol for each of the steps involved in examining virus marker gene …


The Biology Of Reality Testing - Implications For Cognitive Education, Neil Greenberg 2010 University of Tennessee - Knoxville

The Biology Of Reality Testing - Implications For Cognitive Education, Neil Greenberg

Neil Greenberg

• This report explores the proposition that teaching effectiveness can be enhanced by accommodating the key differences between two complementary and deeply engrained modes of reality testing, each predominantly centered in different hemispheres of the brain. • (1) Correspondence involves “reality-testing” of a percept, the cerebral representation of an experience in the world. • (2) Coherence involves “textualizing”, that is, reality-testing of a percept by how easily it relates to previous and ongoing parallel and collateral experiences. • Confidence in the validity of any percept throughout development is related to the interplay of these key processes. • As organisms develop, …


The Delimitation Of Flammulina Fennae, Soňa Ripková, Karen Hughes, Slavomír Adamčík, Viktor Kučera, Katarína Adamčíková 2010 University of Tennessee, Knoxville

The Delimitation Of Flammulina Fennae, Soňa Ripková, Karen Hughes, Slavomír Adamčík, Viktor Kučera, Katarína Adamčíková

Karen Hughes

Multivariate morphometric analyses of micromorphological characters measured on 35 specimens of Flammulina fennae and related species show that only a combination of spore dimensions and ixohyphidia characters are suitable for delimitation of this species. In order to confirm species identifications based on micromorphology, ribosomal ITS DNA sequences were obtained and compared with those previously deposited in GenBank, and phylogenetic analyses were performed using an ITS dataset of all known Flammulina species. All six specimens morphologically determined as F. fennae were identified by molecular data. Two of twelve specimens morphologically assigned to F. velutipes had F. elastica sequences. One ITS sequence …


A New Genus To Accommodate Gymnopus Acervatus (Agaricales), Karen Hughes, David A. Mather, Ronald H. Peterson 2010 University of Tennessee, Knoxville

A New Genus To Accommodate Gymnopus Acervatus (Agaricales), Karen Hughes, David A. Mather, Ronald H. Peterson

Karen Hughes

Phylogenies based on ITS and LSU nrDNA sequences show Agaricus (Gymnopus) acervatus as unique within the Gymnopus/Rhodocollybia complex. These phylogenies imply that a separate genus is necessary, and Connopus is proposed. Infraspecific morphological and DNA-based variation within C. acervatus suggests that a western North American clade might be reproductively isolated from the eastern North American/Scandinavian clade and that in this species complex the European and eastern North American clade might be conspecific. A Scandinavian exemplar is selected for bar-coding. Two GenBank sequences with name-phylogenetic placement inconsistencies are identified.


Enzyme Entrapment In Reprecipitated Polyaniline Nano- And Microparticles, Louis R. Nemzer, Austin Schwartz, Arthur Epstein 2010 Nova Southeastern University

Enzyme Entrapment In Reprecipitated Polyaniline Nano- And Microparticles, Louis R. Nemzer, Austin Schwartz, Arthur Epstein

Louis R Nemzer

We introduce a novel method for fabricating nano- and microscale polyaniline particles containing an entrapped oxidoreductase enzyme for use in biosensing applications. This facile process utilizes the reprecipitation of the emeraldine base form of polyaniline from an aqueous-organic suspension, with hydrophobic collapse and subsequent cross-linking of the polymer induced by adjusting the ionic strength beyond a critical threshold. We present UV-vis spectroscopy data, including a quantitative treatment of the spectral line width, along with dynamic light scatting results, to explain the conformation changes in the polyaniline chains that accompany this transition. The resultant aggregated supermolecular polyaniline formations immobilize enzymes via …


Shearwater Foraging In The Southern Ocean: The Roles Of Prey Availability And Winds, B Raymond, Scott A. Shaffer, S Sokolov, E Woehler, D P. Costa, L Einoder, M Hindell, G Hosie, M Pinkerton, P M. Sagar, D Scott, A Smith, D R. Thompson, C Vertigan, H Weimerskirch 2010 San Jose State University

Shearwater Foraging In The Southern Ocean: The Roles Of Prey Availability And Winds, B Raymond, Scott A. Shaffer, S Sokolov, E Woehler, D P. Costa, L Einoder, M Hindell, G Hosie, M Pinkerton, P M. Sagar, D Scott, A Smith, D R. Thompson, C Vertigan, H Weimerskirch

Scott A. Shaffer

Background Sooty (Puffinus griseus) and short-tailed (P. tenuirostris) shearwaters are abundant seabirds that range widely across global oceans. Understanding the foraging ecology of these species in the Southern Ocean is important for monitoring and ecosystem conservation and management. Methodology/Principal Findings Tracking data from sooty and short-tailed shearwaters from three regions of New Zealand and Australia were combined with at-sea observations of shearwaters in the Southern Ocean, physical oceanography, near-surface copepod distributions, pelagic trawl data, and synoptic near-surface winds. Shearwaters from all three regions foraged in the Polar Front zone, and showed particular overlap in the region around 140°E. Short-tailed shearwaters …


Grappling With Climate Change: Impacts To Heritage Resources, Lauren Meyer, Pei-Lin Yu, Randall Skeirik, Virginia Salazar-Halfmoon 2010 Boise State University

Grappling With Climate Change: Impacts To Heritage Resources, Lauren Meyer, Pei-Lin Yu, Randall Skeirik, Virginia Salazar-Halfmoon

Pei-Lin Yu

17th century adobe walls collapsing at Tumacácori; historic inscriptions rapidly eroding at El Morro; ancestral pueblo field houses at Bandelier impacted by significant soil erosion. Is this deterioration and loss the result of a lack of proper maintenance, a misunderstanding of the needs of fragile site materials, the cumulative effects of 'normal' deterioration, or the result of random and unpredictable natural events and material failures? Could any (or all) of it be related to climate change? As a cultural resource manager, climate change is a difficult matter to grapple with. Can one comfortably say that a wall collapse is the …


Poleward Transport Of Tpx2 In The Mammalian Mitotic Spindle Requires Dynein, Eg5, And Microtubule Flux, Patricia Wadsworth, N. Ma, S. Tulu, N. Ferenz, C. Fagerstrom, A. Mogilner 2010 University of Massachusetts - Amherst

Poleward Transport Of Tpx2 In The Mammalian Mitotic Spindle Requires Dynein, Eg5, And Microtubule Flux, Patricia Wadsworth, N. Ma, S. Tulu, N. Ferenz, C. Fagerstrom, A. Mogilner

Patricia Wadsworth

TPX2 is a Ran-regulated spindle assembly factor that is required for kinetochore fiber formation and activation of the mitotic kinase Aurora A. TPX2 is enriched near spindle poles and is required near kinetochores, suggesting that it undergoes dynamic relocalization throughout mitosis. Using photoactivation, we measured the movement of PA-GFP-TPX2 in the mitotic spindle. TPX2 moves poleward in the half-spindle and is static in the interzone and near spindle poles. Poleward transport of TPX2 is sensitive to inhibition of dynein or Eg5 and to suppression of microtubule flux with nocodazole or antibodies to Kif2a. Poleward transport requires the C terminus of …


Multiple Domains In The Crumbs Homolog 2a (Crb2a) Protein Are Required For Regulating Rod Photoreceptor Size, Abigail Jensen, Y. C. Hsu 2010 University of Massachusetts - Amherst

Multiple Domains In The Crumbs Homolog 2a (Crb2a) Protein Are Required For Regulating Rod Photoreceptor Size, Abigail Jensen, Y. C. Hsu

Abigail Jensen

Background Vertebrate retinal photoreceptors are morphologically complex cells that have two apical regions, the inner segment and the outer segment. The outer segment is a modified cilium and is continuously regenerated throughout life. The molecular and cellular mechanisms that underlie vertebrate photoreceptor morphogenesis and the maintenance of the outer segment are largely unknown. The Crumbs (Crb) complex is a key regulator of apical membrane identity and size in epithelia and in Drosophila photoreceptors. Mutations in the human gene CRUMBS HOMOLOG 1 (CRB1) are associated with early and severe vision loss. Drosophila Crumbs and vertebrate Crb1 and Crumbs homolog 2 (Crb2) …


Myosin Xi Is Essential For Tip Growth In Physcomitrella Patens, L Vidali, GM Burkart, RC Augustine, E Kerdavid, E Tuzel, M Bezanilla 2010 University of Massachusetts - Amherst

Myosin Xi Is Essential For Tip Growth In Physcomitrella Patens, L Vidali, Gm Burkart, Rc Augustine, E Kerdavid, E Tuzel, M Bezanilla

Magdalena Bezanilla

Class XI myosins are plant specific and responsible for cytoplasmic streaming. Because of the large number of myosin XI genes in angiosperms, it has been difficult to determine their precise role, particularly with respect to tip growth. The moss Physcomitrella patens provides an ideal system to study myosin XI function. P. patens has only two myosin XI genes, and these genes encode proteins that are 94% identical to each other. To determine their role in tip growth, we used RNA interference to specifically silence each myosin XI gene using 5′ untranslated region sequences. We discovered that the two myosin XI …


Effects Of Intimate Partner Violence On Pregnancy Trauma And Placental Abruption, Sandra D. Lane, J. Leone, E. H. Koumans, K. Demott, M. Wojtowycs, J. Jenson 2010 Syracuse University

Effects Of Intimate Partner Violence On Pregnancy Trauma And Placental Abruption, Sandra D. Lane, J. Leone, E. H. Koumans, K. Demott, M. Wojtowycs, J. Jenson

Sandra D. Lane

No abstract provided.


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