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Articles 10411 - 10440 of 10788
Full-Text Articles in Entire DC Network
The Functions Of The Executive And The Republic: Exploring The Platonic Roots Of Chester Barnard, Paul C. Godfrey
The Functions Of The Executive And The Republic: Exploring The Platonic Roots Of Chester Barnard, Paul C. Godfrey
Faculty Publications
This essay examines the similarities between Plato's Republic and Barnard's Functions of the Executive. The essay argues that comparisons between Barnard and Plato are not overstated in form or substance. Three major areas of each work are compared: the ethical foundations, the political foundations, and the role of education in achieving those political means. Implications arising from the comparison are discussed and the essay concludes by linking the Barnard- Plato dialogue with current issues in management theory and practice.
Morphometry Of Growth In Hatchling Striped Plateau Lizards (Iguanidae: Sceloporus Virgatus), Geoffrey R. Smith
Morphometry Of Growth In Hatchling Striped Plateau Lizards (Iguanidae: Sceloporus Virgatus), Geoffrey R. Smith
Faculty Publications
No abstract provided.
Country/Region Reports -- United States Of America, Linda A. Malone
Country/Region Reports -- United States Of America, Linda A. Malone
Faculty Publications
No abstract provided.
Evolving Consensus: The Dynamic Future Of Environmental Law And Policy, Ronald H. Rosenberg
Evolving Consensus: The Dynamic Future Of Environmental Law And Policy, Ronald H. Rosenberg
Faculty Publications
No abstract provided.
Arabidopsis Glabrous1 Gene Requires Downstream Sequences For Function, J. C. Larkin, D. G. Oppenheimer, S. Pollock, M. D. Marks
Arabidopsis Glabrous1 Gene Requires Downstream Sequences For Function, J. C. Larkin, D. G. Oppenheimer, S. Pollock, M. D. Marks
Faculty Publications
No abstract provided.
Structure Of The Epididymal Retinoic Acid Binding Protein At 2.1 Å Resolution, Marcia E. Newcomer
Structure Of The Epididymal Retinoic Acid Binding Protein At 2.1 Å Resolution, Marcia E. Newcomer
Faculty Publications
Background: Androgen-dependent proteins in the lumen of the epididymis are required for sperm maturation. One of these is a retinoic acid binding protein, E-RABP, which binds both all-trans and 9-cis retinoic acid. The other retinoid-binding proteins whose structures are known do not bind 9-cis retinoids. Results: We describe the X-ray structure determination of E-RABP with and without bound ligand. The ligand binds deep in the β-barrel of the protein, the β-ionone ring innermost. The binding site, like the ligand, is amphipathic and the deepest part of the cavity is formed by a ring of aromatic amino acids. The isoprene tail …
Physical Inactivity. Workshop V. Aha Prevention Conference Iii. Behavior Change And Compliance: Keys To Improving Cardiovascular Health, Steven N. Blair, Kenneth E. Powell, Terry L. Bazzarre, James L. Early, Leonard H. Epstein, Lawrence W. Green, Sally S. Harris, William L. Haskell, Abby C. King, Jeffrey Koplan, Bess H. Marcus, Ralph S. Paffenbarger Jr., Kimberly K. Yeager
Physical Inactivity. Workshop V. Aha Prevention Conference Iii. Behavior Change And Compliance: Keys To Improving Cardiovascular Health, Steven N. Blair, Kenneth E. Powell, Terry L. Bazzarre, James L. Early, Leonard H. Epstein, Lawrence W. Green, Sally S. Harris, William L. Haskell, Abby C. King, Jeffrey Koplan, Bess H. Marcus, Ralph S. Paffenbarger Jr., Kimberly K. Yeager
Faculty Publications
No abstract provided.
Distributions Of Pigments And Primary Production In A Gulf-Stream Meander, Steven E. Lohrenz, John J. Cullen, David A. Phinney, Donald B. Olson, Charles S. Yentsch
Distributions Of Pigments And Primary Production In A Gulf-Stream Meander, Steven E. Lohrenz, John J. Cullen, David A. Phinney, Donald B. Olson, Charles S. Yentsch
Faculty Publications
An investigation was made of physical effects of Gulf Stream meandering on the vertical and horizontal distributions of photosynthetic pigments and primary production. Cruises were conducted in the vicinity of a meander east of 73-degrees-W and north of 37-degrees-N from September 21 to October 5 (leg 1) and October 12-21, 1988 (leg 2), on the R/V Cape Hatteras. Relationships of photosynthesis (normalized to chlorophyll) to irradiance (P-1) did not show large horizontal variation, and water column composite P-I curves from leg 1 and leg 2 were similar. Therefore a single P-I curve derived from pooled data was used to model …
The Legal Significance Of Gestation, Larry I. Palmer
The Legal Significance Of Gestation, Larry I. Palmer
Faculty Publications
No abstract provided.
Formation Of O-Tyrosine And Dityrosine In Proteins During Radiolytic And Metal-Catalyzed Oxidation, Thomas G. Huggins, Mary C. Wells-Knecht, Nicholas A. Detorie, John W. Baynes, Suzanna R. Thorpe
Formation Of O-Tyrosine And Dityrosine In Proteins During Radiolytic And Metal-Catalyzed Oxidation, Thomas G. Huggins, Mary C. Wells-Knecht, Nicholas A. Detorie, John W. Baynes, Suzanna R. Thorpe
Faculty Publications
To evaluate their usefulness as chemical indicators of cumulative oxidative damage to proteins, we studied the kinetics and extent of formation of ortho-tyrosine (0-Tyr), dityrosine (DT), and dityrosine-like fluorescence (Ex = 3 17 nm, E,,, = 407 nm) in the model proteins RNase and lysozyme exposed to radiolytic and metalcatalyzed (H20z/Cu2+) oxidation (MCO). Although there were protein-dependent differences, o-Tyr, DT, and fluorescence increased coordinately during oxidation of the proteins in both oxidation systems. The contribution of DT to total dityrosine-like fluorescence in oxidized proteins varied from 2-10070, depending on the protein, type of oxidation, and extent of oxidative damage. In …
Oxidized Amino Acids In Lens Protein With Age: Measurement Of O-Tyrosine And Dityrosine In The Aging Human Lens, Mary C. Wells-Knect, Thomas G. Huggins, Daniel G. Dyer, Suzanne R. Thorpe, John W. Baynes
Oxidized Amino Acids In Lens Protein With Age: Measurement Of O-Tyrosine And Dityrosine In The Aging Human Lens, Mary C. Wells-Knect, Thomas G. Huggins, Daniel G. Dyer, Suzanne R. Thorpe, John W. Baynes
Faculty Publications
The concentrations of ortho-tyrosine (o-Tyr) and dityrosine (DT) were measured in noncataractous human lenses in order to assess the role of proteinoxidation reactions in the aging of lens proteins. The measurements were conducted by selected ion monitoring-gas chromatography/mass spectrometry using deuterium-labeled internal standards, which provided both high sensitivity and specificity for the quantitation of o-Tyr and DT. Between ages 1 and 78 years, the o-Tyr concentration in lens proteins varied from 0.3 to 0.9 mmol of o-Tyr/mol of Phe (n = 19), while DT ranged from 1 to 3 mumol of DT/mol of Tyr (n = 30). There were no …
Development Of New Methods For Assessing Solidification/Stabilization Of Hazardous Waste Using Solid-State Nuclear Magnetic Resonance Techniques (Ph.D Dissertation, Lsu), Michael A. Janusa
Development Of New Methods For Assessing Solidification/Stabilization Of Hazardous Waste Using Solid-State Nuclear Magnetic Resonance Techniques (Ph.D Dissertation, Lsu), Michael A. Janusa
Faculty Publications
New methods for assessing solidification/stabilization (S/S) of hazardous waste using solid-state nuclear magnetic resonance are developed for the purpose of diagnosing on a microscopic level the performance of S/S as a hazardous waste disposal technique. There are four techniques developed and described in this dissertation: (1) Solid-state deuterium NMR spectroscopy is used to determine if a particular deuterated organic waste is effectively solidified/stabilized and to determine the lower limit of the bond strength between the waste and the cement matrix; (2) Constant time pulsed field gradient ^ NMR spectroscopy is tested on a liquid waste encapsulated within a solidified matrix …
Rule Of Law In Legal And Economic Theory, Noel B. Reynolds
Rule Of Law In Legal And Economic Theory, Noel B. Reynolds
Faculty Publications
Legal positivism, the leading version of legal theory, has shown that a concentration on the meanings and logical relations of legal concepts, however much supplemented by intuition, common sense and legal experience, is not adequate to make full sense out of the human experience of law, and the traditional understandings of legal obligation and rule of law in particular. However, modern economic science has advanced a radically individualistic theoretical approach which has propelled economics to the fore as the most successful of the social sciences. And its basic theoretical stance is proving both attractive and adaptable to all the other …
Decomposition Of Senescent Blades Of The Seagrass Halodule Wrightii In A Subtropical Lagoon, Stephen Opsahl, Ronald Benner
Decomposition Of Senescent Blades Of The Seagrass Halodule Wrightii In A Subtropical Lagoon, Stephen Opsahl, Ronald Benner
Faculty Publications
Senescent blades from the seagrass Halodule wrightii Aschers were suspended in the water column of Laguna Madre (Texas, USA) for a period of 419 d, representing the longest seagrass decomposition study to date. The initial stage of decomposition was characterized by a rapid loss of organic matter (36 % in 24 d) attributed to leaching. A total of 76 % of the organic matter from seagrass tissues was lost by the end of the decomposition period. Of the major bulk constituents measured, neutral sugars were most abundant and accounted for 23 % of the ash-free dry wt of the initial …
Big Mother: The State's Use Of Mental Health Experts In Dependency Cases, George J. Alexander
Big Mother: The State's Use Of Mental Health Experts In Dependency Cases, George J. Alexander
Faculty Publications
No abstract provided.
Analysis Of Weighted Fan-Out/Fan-In Volume Holographic Interconnections, Gregory P. Nordin, P. Asthana, B. Keith Jenkins, A. R. Tanguay
Analysis Of Weighted Fan-Out/Fan-In Volume Holographic Interconnections, Gregory P. Nordin, P. Asthana, B. Keith Jenkins, A. R. Tanguay
Faculty Publications
The feasibility of employing volume holographic techniques for the implementation of highly multiplexed weighted fan-out/fan-in interconnections is analyzed on the basis of interconnection fidelity, optical throughput, and complexity of recording schedule or implementation hardware. These feasibility criteria were quantitatively evaluated using the optical beam propagation method to numerically simulate the diffraction characteristics of volume holographic interconnections recorded in a linear holographic material. We find that conventional interconnection architectures (that are based on a single coherent optical source) exhibit a direct trade-off between interconnection fidelity and optical throughput on the one hand, and recording schedule or hardware complexity on the other. …
An Inservice Model To Impact Life-Science Classroom Practice: Part Two, David P. Butts, Wyatt Anderson, Mary Atwater, Thomas Koballa, Patricia Simmons, Rosalina Hairston
An Inservice Model To Impact Life-Science Classroom Practice: Part Two, David P. Butts, Wyatt Anderson, Mary Atwater, Thomas Koballa, Patricia Simmons, Rosalina Hairston
Faculty Publications
This model for an inservice program describes why teachers change the nature of their students' experiences in science. In the evaluation study with 7th grade Life Science teachers in Southeast, evidence showed that as teachers' knowledge in specific topics in biology was enhanced, their classroom use of this knowledge also changed. As their knowledge of science and alternative teaching practices was expanded, their attitudes toward teaching showed that they were more aware that there was more to learn but were also more confident that they could acquire the new knowledge they needed. In their classroom, their concerns for students showed …
Endogenous Retinoids In Rat Epididymal Tissue And Rat And Human Spermatozoa, R. S. Pappas, M. E. Newcomer, D. E. Ong
Endogenous Retinoids In Rat Epididymal Tissue And Rat And Human Spermatozoa, R. S. Pappas, M. E. Newcomer, D. E. Ong
Faculty Publications
Recent work has demonstrated high levels of retinoid binding proteins in rat epididymis, and a lumenal retinoic acid binding protein has been purified. These findings suggested that vitamin A may be involved in spermatozoal maturation in the epididymis. We further addressed this question by quantifying retinol, retinyl esters, and retinoic acid isomers from perfused epididymal tissue, from rat testicular and epididymal spermatozoa, and from human ejaculate sperm. HPLC showed vitamin A levels to be higher in caput than in corpus or cauda tissue. Retinoic acid and 9-cis-retinoic acid were found to be graded from lowest levels in caput to highest …
Carbon, Nitrogen, And Phosphorus Leaching Rates From Spartina Alterniflora Salt Marshes, R. Eugene Turner
Carbon, Nitrogen, And Phosphorus Leaching Rates From Spartina Alterniflora Salt Marshes, R. Eugene Turner
Faculty Publications
Annual carbon, nitrogen, and phosphorus leachate rates from live Spartina alterniflora Loisel in a Louisiana (USA) salt marsh were estimated to be 200, 14, and 3 g m-2, respectively, and to peak in summer and higher salinit~es. Leachate losses of P, N and C are equivalent to a turnover of live plant tissues of 10, 17 and 49 d, respectively, when submerged, and 148, 250 and 721 d, respectively, when unsubmerged. Plant leachate losses during marsh submergence and non-submergence are nearly equal because release rates are 15x greater during submergence. Nitrogen and carbon concentrations relative to phosphorus are proportionately 4x …
Evaluating Susceptibility Of Red-Cockaded Woodpecker Cavity Trees To Southern Pine Beetle In Texas, William G. Ross, David Kulhavy, Richard N. Conner
Evaluating Susceptibility Of Red-Cockaded Woodpecker Cavity Trees To Southern Pine Beetle In Texas, William G. Ross, David Kulhavy, Richard N. Conner
Faculty Publications
Characteristics of loblolly (Pinus fuedu L.) and shortleaf (Pinus echinutu Mill.) pine trees favored by the endangered red-cockaded woodpecker, Picuides borealis (Vieillot) for nesting and roosting cavities over much of eastern Texas, tend to make these trees highly vulnerable to mortality from bark beetle attack. Resin flow and xylem moisture potential, often used as indicators of pine susceptibility to bark beetle mortality, were measured in several red-cockaded woodpecker cavity tree clusters in the Angelina and Davy Crockett National Forests. No differences in xylem moisture potential were found, while resin flow varied by site, tree species, and cavity tree type. With …
Endocytosis In Plant Protoplasts: Visualization And Quantitation Of Fluid-Phase Endocytosis Using Silver-Enhanced Bovine Serum Albumin-Gold [Abstract], Marco A. Villanueva, Josephine Taylor, Lawrence R. Griffing
Endocytosis In Plant Protoplasts: Visualization And Quantitation Of Fluid-Phase Endocytosis Using Silver-Enhanced Bovine Serum Albumin-Gold [Abstract], Marco A. Villanueva, Josephine Taylor, Lawrence R. Griffing
Faculty Publications
No abstract provided.
Forest Pest Management On Typic Quartzipsamments: A Management Dilemma, R. R. Cahal, David L. Kulhavy, W. G. Ross, W. D. Tracey, W. D. Hacker
Forest Pest Management On Typic Quartzipsamments: A Management Dilemma, R. R. Cahal, David L. Kulhavy, W. G. Ross, W. D. Tracey, W. D. Hacker
Faculty Publications
Pine plantations on Typic Quartzipsamments in East Texas are difficult to establish. Forest management options following clearcutting are limited. A eight year regeneration study of the growth and survival of loblolly, Pinus tuedu, L. shortleaf, P. echinutu Mill., slash, P. elliofii Engelm and longleaf pines P. palustris Mill. was conducted to determine optimum tree species and treatments for reforestation; and to recommend practical alternative land uses and management strategies for Typic Quartzipsamrnents. With successful regeneration also comes insects and pathogens. Impacts of the Nantucket pine tip moth, Rhyacioniujkstrunu, (Comstock) the Deodar weevil, Pissodes nernorensis, Germar, Annosus root rot, Heterobusidion unnosusm …
Activity Patterns And Habitat Use Of Northern Bobwhite Females In 2 Grazing Systems, R. Montague Whiting Jr., Denise L. Sloan
Activity Patterns And Habitat Use Of Northern Bobwhite Females In 2 Grazing Systems, R. Montague Whiting Jr., Denise L. Sloan
Faculty Publications
During spring and summer of 1985 and 1986, we investigated activity patterns and habitat use of female northern bobwhite (Colinus virginianus) on 2 sites in south Texas. One site had been subjected to a short duration grazing (SDG) system and the other to a continuous grazing (CG) system. Nineteen females were radio-tagged in 1985 and 28 in 1986. Rainfall was above average in 1985 and below average in 1986; as a result, herbaceous ground cover was more dense in 1985 than in 1986. Due to extensive fencing, 58% of the SDG cell was within 25 m of a mowed roadside, …
Carbon, Nitrogen, And Phosphorus Leaching Rates From Spartina-Alterniflora Salt Marshes, R E. Turner
Carbon, Nitrogen, And Phosphorus Leaching Rates From Spartina-Alterniflora Salt Marshes, R E. Turner
Faculty Publications
Annual carbon, nitrogen, and phosphorus leachate rates from live Spartina alterniflora Loisel in a Louisiana (USA) salt marsh were estimated to be 200, 14, and 3 g M-2, respectively, and to peak in summer and higher salinities. Leachate losses of P, N and C are equivalent to a turnover of live plant tissues of 10, 17 and 49 d, respectively, when submerged, and 148, 250 and 721 d, respectively, when unsubmerged. Plant leachate losses during marsh submergence and non-submergence are nearly equal because release rates are 15 x greater during submergence. Nitrogen and carbon concentrations relative to phosphorus are proportionately …
Differential Susceptibility Of Guanine Nucleotide-Binding Proteins To Pertussis Toxin-Catalyzed Adp-Ribosylation In Brain Membranes Of Two Congeneric Marine Fishes, T. F. Murray, J. F. Siebenaller
Differential Susceptibility Of Guanine Nucleotide-Binding Proteins To Pertussis Toxin-Catalyzed Adp-Ribosylation In Brain Membranes Of Two Congeneric Marine Fishes, T. F. Murray, J. F. Siebenaller
Faculty Publications
No abstract provided.
Synaptic Transmission Between Pairs Of Retinal Amacrine Cells In Culture, E. Gleason, S. Borges, M. Wilson
Synaptic Transmission Between Pairs Of Retinal Amacrine Cells In Culture, E. Gleason, S. Borges, M. Wilson
Faculty Publications
We have examined synaptic transmission between isolated pairs of chick GABAergic amacrine cells, maintained in sparse culture and identified by their binding of an amacrine cell-selective antibody. Using the perforated- patch method to whole-cell clamp both cells of a pair, postsynaptic currents were examined for step depolarizations of the 'presynaptic' cell. Synaptic transmission, frequently reciprocal, was calcium dependent and reversibly blocked by bicuculline. Postsynaptic currents, excluding those due to ohmic electrical coupling, were elicited only for presynaptic voltage steps positive to about -40 mV and were always very noisy, suggesting that they were summed from relatively small numbers of quanta. …
Design Of A Functional Calcium Channel Protein: Inferences About An Ion Channel‐Forming Motif Derived From The Primary Structure Of Voltage‐Gated Calcium Channels, Anne Grove, John M. Tomich, Takeo Iwamoto, Mauricio Montal
Design Of A Functional Calcium Channel Protein: Inferences About An Ion Channel‐Forming Motif Derived From The Primary Structure Of Voltage‐Gated Calcium Channels, Anne Grove, John M. Tomich, Takeo Iwamoto, Mauricio Montal
Faculty Publications
To identify sequence‐specific motifs associated with the formation of an ionic pore, we systematically evaluated the channel‐forming activity of synthetic peptides with sequence of predicted transmembrane segments of the voltage‐gated calcium channel. The amino acid sequence of voltage‐gated, dihydropyridine (DHP)‐sensitive calcium channels suggests the presence in each of four homologous repeats (I–IV) of six segments (S1–S6) predicted to form membrane‐spanning, α‐helical structures. Only peptides representing amphipathic segments S2 or S3 form channels in lipid bilayers. To generate a functional calcium channel based on a four‐helix bundle motif, four‐helix bundle proteins representing IVS2 (T4CaIVS2) or IVS3 (T4CaIVS3) were synthesized. Both proteins …
Glucose Uptake And End Product Formation In An Intertidal Marine Sediment, T. E. Sawyer, G. M. King
Glucose Uptake And End Product Formation In An Intertidal Marine Sediment, T. E. Sawyer, G. M. King
Faculty Publications
Glucose uptake was monitored on a seasonal basis, using [6-3H]glucose and undisturbed cores collected from an intertidal mud flat. The fate of glucose carbon, including the formation of CO2 and biomass, was assayed by using undisturbed cores and [U-14C]glucose; the production of short-chain fatty acids was monitored with [U-14C]glucose and sediment slurries. Rate constants for glucose uptake varied temporally, with temperature accounting for much of the variability; turnover times ranged from about 2 to 10 min. Rate constants decreased with increasing sediment depth and in the following order for several common monosaccharides: glucose>galactose>mannose~fucose. Time course analyses of 14CO2 …
Methane Consumption In Temperate And Subarctic Forest Soils: Rates, Vertical Zonation, And Responses To Water And Nitrogen, A. P.S. Adamsen, G. M. King
Methane Consumption In Temperate And Subarctic Forest Soils: Rates, Vertical Zonation, And Responses To Water And Nitrogen, A. P.S. Adamsen, G. M. King
Faculty Publications
Rates of methane consumption were measured in subarctic coniferous and temperate mixed-hardwood forest soils, using static chambers and intact soil cores. Rates at both sites were generally between 1 and 3 mg of CH4 m-2 day-1 and decreased with increasing soil water contents above 20%. Addition of ammonium (1 μmol g of soil-1) strongly inhibited methane oxidation in the subarctic soils; a lesser inhibition was observed for temperate forest samples. The response to nitrogen additions occurred within a few hours and was probably due to physiological changes in the active methane-consuming populations. Methane consumption in soils from both sites was …
Application Of A Tetrazolium Salt With A Water-Soluble Formazan As An Indicator Of Viability In Respiring Bacteria, P. Roslev, G. M. King
Application Of A Tetrazolium Salt With A Water-Soluble Formazan As An Indicator Of Viability In Respiring Bacteria, P. Roslev, G. M. King
Faculty Publications
The tetrazolium salt sodium 3'-{1-[(phenylamino)-carbonyl]-3,4- tetrazolium}-bis (4-methoxy-6-nitro)benzene-sulfonic acid hydrate (XTT) was examined for use as a colorimetric indicator of viability in respiring bacteria. XTT was reduced to an orange, water-soluble formazan product by Methylosinus trichosporium OB3b, Pseudomonas putida, Escherichia coli, and Bacillus subtilis. Formazan production was proportional to live cell biomass, and XTT was reduced by all cultures in the absence of added electron-coupling agents. XTT reduction by M. trichosporium OB3b was linear over several hours and was stimulated by the presence of an exogenous substrate (methanol). Addition of cyanide to cultures incubated under oxic conditions gave an initial 10-fold …