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196,625 full-text articles. Page 4948 of 4952.

The Ecology Of Speciation In Bacillus, Nora Connor, Johannes Sikorski, Alejandro P. Rooney, Sarah Kopac, Alexander F. Koeppel, Andrew Burger, Scott G. Cole, Elizabeth B. Perry, Danny Krizanc, Nicholas C. Field, Michele Slaton, Frederick M. Cohan 2009 Wesleyan University

The Ecology Of Speciation In Bacillus, Nora Connor, Johannes Sikorski, Alejandro P. Rooney, Sarah Kopac, Alexander F. Koeppel, Andrew Burger, Scott G. Cole, Elizabeth B. Perry, Danny Krizanc, Nicholas C. Field, Michele Slaton, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.


The Genome Of Geobacter Bemidjiensis, Exemplar For The Subsurface Clade Of Geobacter Species That Predominate In Fe(Iii)-Reducing Subsurface Enviorments, Derek Lovley, Muktak Aklujkar, Nealson D. Young, Dawn Holmes, Milind Chavan, Carla Risso, Hajnalka E. Kiss, Cliff S. Han, Miriam L. Land 2009 University of Massachusetts - Amherst

The Genome Of Geobacter Bemidjiensis, Exemplar For The Subsurface Clade Of Geobacter Species That Predominate In Fe(Iii)-Reducing Subsurface Enviorments, Derek Lovley, Muktak Aklujkar, Nealson D. Young, Dawn Holmes, Milind Chavan, Carla Risso, Hajnalka E. Kiss, Cliff S. Han, Miriam L. Land

Carla Risso

BACKGROUND: Geobacter species in a phylogenetic cluster known as subsurface clade 1 are often the predominant microorganisms in subsurface environments in which Fe(III) reduction is the primary electron-accepting process. Geobacter bemidjiensis, a member of this clade, was isolated from hydrocarbon-contaminated subsurface sediments in Bemidji, Minnesota, and is closely related to Geobacter species found to be abundant at other subsurface sites. This study examines whether there are significant differences in the metabolism and physiology of G. bemidjiensis compared to non-subsurface Geobacter species. RESULTS: Annotation of the genome sequence of G. bemidjiensis indicates several differences in metabolism compared to previously sequenced ...


A Simplified Method For Monitoring Progestagens In African Elephants Under Field Conditions, Bruce A. Schulte, Elizabeth W. Freeman, F. Nicole Abbondanza, Jordana M. Meyer, Janine L. Brown 2009 Western Kentucky University

A Simplified Method For Monitoring Progestagens In African Elephants Under Field Conditions, Bruce A. Schulte, Elizabeth W. Freeman, F. Nicole Abbondanza, Jordana M. Meyer, Janine L. Brown

Bruce A. Schulte

Summary
1. Hormone analyses are frequently used to support management of wildlife; however, current techniques are not very field-friendly. In situ hormone monitoring is often expensive, time consuming and logistically difficult. Thus, a new method for assessing ovarian cycle activity non-invasively in free-ranging African elephants was developed. 2. The technique involves handshaking faecal samples in common organic solvents, use of environmentally stable antibody-coated microtitre plates and assessment of progestagen concentrations based on a visual colour change.
3. Studies using ex situ African elephants determined that handshaking faeces in a solution of isopropyl alcohol was effective for extracting the faecal progestagens ...


Cortical Underconnectivity Coupled With Preserved Visuospatial Cognition In Autism: Evidence From An Fmri Study Of An Embedded Figures Task, Saudamini Damarla, Timothy A. Keller, Rajesh K. Kana, Vladimir L. Cherkassky, Diane L. Williams, Nancy J. Minshew, Marcel Adam Just 2009 Carnegie Mellon University

Cortical Underconnectivity Coupled With Preserved Visuospatial Cognition In Autism: Evidence From An Fmri Study Of An Embedded Figures Task, Saudamini Damarla, Timothy A. Keller, Rajesh K. Kana, Vladimir L. Cherkassky, Diane L. Williams, Nancy J. Minshew, Marcel Adam Just

Marcel Adam Just

No abstract provided.


Regulatory Elements Of Xenopus Col2a1 Drive Cartilaginous Gene Expression In Transgenic Frogs, Ryan Kerney, Brian K. Hall, James Hanken 2009 Dalhousie University

Regulatory Elements Of Xenopus Col2a1 Drive Cartilaginous Gene Expression In Transgenic Frogs, Ryan Kerney, Brian K. Hall, James Hanken

Ryan Kerney

This study characterizes regulatory elements of collagen 2α1 (col2a1) in Xenopus that enable transgene expression in cartilage-forming chondrocytes. The reporters described in this study drive strong cartilage-specific gene expression, which will be a valuable tool for further investigations of Xenopus skeletal development. While endogenous col2a1 mRNA is expressed in many embryonic tissues, its expression becomes restricted to tadpole and adult chondrocytes. This chondrocyte-specific expression is recapitulated by col2a1 reporter constructs, which were tested through I-SceI meganuclease-mediated transgenesis. These constructs contain a portion of the Xenopus tropicalis col2a1 intron, which aligns to a cartilage-specific intronic enhancer that has been well characterized ...


Food Technology, Innovation And Teacher Education Summary Of Survey Findings, Angela Turner 2009 Southern Cross University

Food Technology, Innovation And Teacher Education Summary Of Survey Findings, Angela Turner

Dr Angela Turner

This executive summary presents an overview of the findings from data collected during 2009 as part of a doctoral thesis entitled: A Critique of Food Technology, Innovation and Teacher Education. The survey instrument collected information that sought to establish contemporary perceptions about the study of Food Technology in Australia and the role secondary education may play in ‘supplying’ people into professional studies towards a career as a food technologist. In this arrangement, the industry and profession of food technologists represent the ‘demand’ side of the process that starts with receiving students ‘supplied’ by the schools sector into undergraduate food science ...


Quantitativepcrmethods Forrna Anddnainmarine Sediments: Maximizing Yieldwhile Overcoming Inhibition, Karen Lloyd, Barbara J. MacGregor, Andreas Teske 2009 Selected Works

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 ...


Neurosteroids On The Epilepsy Chessboard — Keeping Seizures In Check, Michael A. Rogawski 2009 University of California - Davis

Neurosteroids On The Epilepsy Chessboard — Keeping Seizures In Check, Michael A. Rogawski

Michael A. Rogawski

No abstract provided.


Phase-Linking And The Perceived Motion During Off-Vertical Axis Rotation, Jan E. Holly, Scott J. Wood, Gin McCollum 2009 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 ...


Treatment Of Early And Late Kainic-Acid Induced Status Epilepticus With The Non-Competitive Ampa Receptor Antagonist Gyki 52466, Brita Fritsch, Jeffrey J. Stott, J. Joelle Donofrio, Michael A. Rogawski 2009 University of Minnesota

Treatment Of Early And Late Kainic-Acid Induced Status Epilepticus With The Non-Competitive Ampa Receptor Antagonist Gyki 52466, Brita Fritsch, Jeffrey J. Stott, J. Joelle Donofrio, Michael A. Rogawski

Michael A. Rogawski

Purpose: Benzodiazepines such as diazepam may fail to effectively treat status epilepticus because benzodiazepine-sensitive GABA-A receptors are internalized progressively with continued seizure activity. Ionotropic glutamate receptors, including AMPA receptors, are externalized, so that AMPA receptor antagonists, which are broad-spectrum anticonvulsants, could be more effective treatments for satus epilepticus. We assessed the ability of the non-competitive AMPA receptor antagonist GYKI 52466 to protect against kainic acid-induced status epilepticus in mice. Methods: Groups of animals treated with kainic acid received GYKI 52466 (50 mg/kg followed in 15 min by 50 mg/kg) or diazepam (25 mg/kg followed in 20 min ...


Neighborhood Design And Perceptions: Relationship With Active Commuting, Carolyn C. Voorhees, J. Scott Ashwood, Kelly R. Evenson, John R. Sirard, Ariane L. Rung, Marsha Dowda, Thomas L. McKenzie 2009 University of Massachusetts - Amherst

Neighborhood Design And Perceptions: Relationship With Active Commuting, Carolyn C. Voorhees, J. Scott Ashwood, Kelly R. Evenson, John R. Sirard, Ariane L. Rung, Marsha Dowda, Thomas L. Mckenzie

John Sirard

Purpose—Walking to and from school contributes to total physical activity levels. This study investigated whether perceived and actual neighborhood features were associated with walking to or from school among adolescent girls. Methods—A sample of geographically diverse 8th grade girls (N=890) from the Trial for Activity in Adolescent Girls (TAAG) study living within 1.5 miles of their middle school were recruited. Participants completed a self-administered survey on their neighborhood and walking behavior. Geographic information system (GIS) data were used to assess objective neighborhood features. Nested multivariable logistic regression analyses were conducted to determine the contribution of perceived ...


Before Creation, There Was The Big Bang, Jennifer E. Spreng, Javier M. Leija 2009 Arizona Summit Law School

Before Creation, There Was The Big Bang, Jennifer E. Spreng, Javier M. Leija

Jennifer E Spreng

No abstract provided.


Determining Rates Of Virus Production In Aquatic Systems By The Virus Reduction Approach,, M.G. Weinbauer, J.M. Rowe, Steven Wilhelm 2009 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 ...


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 2009 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 ...


Polyphyly Of The Pikeminnows (Teleostei: Cyprinidae) Inferred Using Mitochondrial Dna Sequences, T. Heath Ogden 2009 Utah Valley University

Polyphyly Of The Pikeminnows (Teleostei: Cyprinidae) Inferred Using Mitochondrial Dna Sequences, T. Heath Ogden

T. Heath Ogden

The phylogenetic relationships of the Colorado pikeminnow Ptychocheilus lucius, northern pikeminnow P. oregonensis, Sacramento pikeminnow P. grandis, Umpqua pikeminnow P. umpquae, and hardhead Mylopharodon conocephalus were examined by using molecular data to investigate monophyly of the genus Ptychocheilus. Phylogenies generated using DNA sequence data from the cytochrome b and 16S ribosomal DNA genes of the mitochondrial genome reveal that Ptychocheilus is a polyphyletic genus and suggest that the taxonomy of the group is in need of further revision. These data yield insights into the evolution of the pikeminnows and help place the significant evolutionary events in context with the geological ...


Anticonvulsant And Proconvulsant Actions Of 2-Deoxy-D-Glucose, Maciej Gasior, Jessica Yankura, Adam L. Hartman, Amy French, Michael A. Rogawski 2009 University of California - Davis

Anticonvulsant And Proconvulsant Actions Of 2-Deoxy-D-Glucose, Maciej Gasior, Jessica Yankura, Adam L. Hartman, Amy French, Michael A. Rogawski

Michael A. Rogawski

Purpose: 2-Deoxy-D-glucose (2-DG), a glucose analog that accumulates in cells and interferes with carbohydrate metabolism by inhibiting glycolytic enzymes, has anticonvulsant actions. Recognizing that severe glucose deprivation can induce seizures, we sought to determine whether acute treatment with 2-DG can promote seizure susceptibility by assessing its effects on seizure threshold. For comparison, we studied 3-methyl-glucose (3-MG), which like 2-DG accumulates in cells and reduces glucose uptake, but does not inhibit glycolysis. Methods: Mice were treated with 2-DG or 3-MG and the seizure threshold determined in the 6-Hz test, the mouse electroshock seizure threshold (MEST) test, and the intravenous pentylenetetrazol (i ...


Anhang: Auszüge Aus Dem Späteren Leben Von Professor Dr. Otto Vogl, Otto Vogl 2009 University of Massachusetts - Amherst

Anhang: Auszüge Aus Dem Späteren Leben Von Professor Dr. Otto Vogl, Otto Vogl

Otto Vogl

No abstract provided.


Phase-Linking And The Perceived Motion During Off-Vertical Axis Rotation, Jan E. Holly, Scott J. Wood, Gin McCollum 2009 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 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 gravitoinertial acceleration (GIA) and (b) that perceived translation arises from perceived linear acceleration, as derived from the portion of the GIA not ...


Ducking As The Means Of Resistance In "Candy-Cane" Stems Of Goldenrod: Straightened Stems Lose Their Edge, M. J. Wise, W. G. Abrahamson, J. A. Cole 2009 Selected Works

Ducking As The Means Of Resistance In "Candy-Cane" Stems Of Goldenrod: Straightened Stems Lose Their Edge, M. J. Wise, W. G. Abrahamson, J. A. Cole

Warren G. Abrahamson, II

Herbivores are among the most pervasive selective forces acting on plants, and the number of plant chemicals that presumably evolved for defense against herbivory is immense. In contrast, biologists are only beginning to appreciate the important roles that architectural traits can play in antiherbivore defense. One putative architectural-resistance trait is the nodding stem apex of some goldenrods (Solidago ; Asteraceae). Individuals of S. altissima genets that undergo temporary nodding in the late spring (i.e., “candy-cane ramets) have been shown to be more resistant than individuals of erect-stemmed genets to certain apex-attacking” herbivores. We tested the hypothesis that the greater resistance ...


Symmetries Of The Central Vestibular System: Forming Movements For Gravity And A Three-Dimensional World, Gin McCollum, Douglas A. Hanes 2009 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.


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