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Protection Of Retinal Cells From Ischemia By A Novel Gap Junction Inhibitor, Satyabrata Das, Dingo Lin, Snehalata Jena, Aibin Shi, Srinivas Battina, Duy H. Hua, Rachel A. Allbaugh, Dolores J. Takemoto Sep 2008

Protection Of Retinal Cells From Ischemia By A Novel Gap Junction Inhibitor, Satyabrata Das, Dingo Lin, Snehalata Jena, Aibin Shi, Srinivas Battina, Duy H. Hua, Rachel A. Allbaugh, Dolores J. Takemoto

Rachel A. Allbaugh

Retinal cells which become ischemic will pass apoptotic signal to adjacent cells, resulting in the spread of damage. This occurs through open gap junctions. A class of novel drugs, based on primaquine (PQ), was tested for binding to connexin 43 using simulated docking studies. A novel drug has been synthesized and tested for inhibition of gap junction activity using R28 neuro-retinal cells in culture. Four drugs were initially compared to mefloquine, a known gap junction inhibitor. The drug with optimal inhibitory activity, PQ1, was tested for inhibition and was found to inhibit dye transfer by 70% at 10 μM. Retinal …


Sequential Reactions With Grubbs Catalyst And Ad-Mix-Alpha/Beta Using Pdms Thimbles, Martin T. Mwangi, Michael D. Schulz, Ned B. Bowden Sep 2008

Sequential Reactions With Grubbs Catalyst And Ad-Mix-Alpha/Beta Using Pdms Thimbles, Martin T. Mwangi, Michael D. Schulz, Ned B. Bowden

Martin M. Thuo

Incompatible Grubbs catalyst and an osmium dihydroxylation catalyst were site-isolated from each other using polydimethylsiloxane thimbles. The Grubbs catalyst was added to the interior of the thimbles, and AD-mix-alpha/beta was added to the exterior. Organic substrates readily fluxed through the walls of the thimbles and reacted with each catalyst. A series of cascade reactions were developed including those with intermediates possessing low boiling points or that were foul smelling.


Improved Uses And Values For The Byproducts Of The Developing Biofuels Industry, Kurt A. Rosentrater Aug 2008

Improved Uses And Values For The Byproducts Of The Developing Biofuels Industry, Kurt A. Rosentrater

Kurt A. Rosentrater

No abstract provided.


Sum Frequency Generation Vibrational Spectroscopy Of Pyridine Hydrogenation On Platinum Nanoparticles, Kaitlin M. Bratlie, Kyriakos Komvopoulos, Gabor A. Somorjai Aug 2008

Sum Frequency Generation Vibrational Spectroscopy Of Pyridine Hydrogenation On Platinum Nanoparticles, Kaitlin M. Bratlie, Kyriakos Komvopoulos, Gabor A. Somorjai

Kaitlin M. Bratlie

Pyridine hydrogenation in the presence of a surface monolayer consisting of cubic Pt nanoparticles stabilized by tetradecyltrimethylammonium bromide (TTAB) was investigated by sum frequency generation (SFG) vibrational spectroscopy using total internal reflection (TIR) geometry. TIR-SFG spectra analysis revealed that a pyridinium cation (C5H5NH+) forms during pyridine hydrogenation on the Pt nanoparticle surface, and the NH group in the C5H5NH+ cation becomes more hydrogen bound with the increase of the temperature. In addition, the surface coverage of the cation decreases with the increase of the temperature. An important contribution of this study is the in situ identification of reaction intermediates adsorbed …


Enantioselective Copper-Catalyzed 1,3-Dipolar Cycloadditions, Levi M. Stanley, Mukund P. Sibi Jul 2008

Enantioselective Copper-Catalyzed 1,3-Dipolar Cycloadditions, Levi M. Stanley, Mukund P. Sibi

Levi M. Stanley

The addition of a 1,3-dipole to an alkene or alkyne is a prominent transformation in organic synthesis.(1) Over the past two decades the intense study of enantioselective 1,3-dipolar cycloaddition methodologies has provided organic chemists with the tools necessary to synthesize a variety of chiral heterocycles in highly enantioenriched forms.(2) The majority of advances in this area are a direct result of studies focusing on chiral Lewis acid-catalyzed or chiral metal-mediated 1,3-dipolar cycloaddition methodologies. It is important to note that even though the many dipoles possess very strong donor atoms it is still possible to carry out enantioselective Lewis acid-catalyzed dipolar …


Copper(Ii)-Catalyzed Exo And Enantioselective Cycloadditions Of Azomethine Imines, Mukund P. Sibi, Digamber Rane, Levi M. Stanley, Takahiro Soeta Jun 2008

Copper(Ii)-Catalyzed Exo And Enantioselective Cycloadditions Of Azomethine Imines, Mukund P. Sibi, Digamber Rane, Levi M. Stanley, Takahiro Soeta

Levi M. Stanley

A strategy for exo and enantioselective 1,3-dipolar cycloaddition of azomethine imines to 2-acryloyl-3-pyrazolidinone is described. The corresponding cycloadducts are isolated with high diastereoselectivities (up to >96:4 exo/endo) and enantioselectivities (up to 98% ee).


Repellent Properties Of Δ-Octalactone Against The Tsetse Fly, Glossina Morsitans Morsitans, Martin T. Mwangi, Nicholas K. Gikonyo, Isaiah O. Ndiege May 2008

Repellent Properties Of Δ-Octalactone Against The Tsetse Fly, Glossina Morsitans Morsitans, Martin T. Mwangi, Nicholas K. Gikonyo, Isaiah O. Ndiege

Martin M. Thuo

δ-octalactone, produced by several Bovidae, has been suggested as a potential repellant of tsetse fly attack. Racemic δ-octalactone was synthesized via an abbreviated route. The product was assayed against 3-day old starved teneral female tsetse flies, Glossina morsitans morsitans Wiedemann (Diptera: Glossinidae), in a choice wind tunnel and found to be a potent tsetse repellent at doses ≥0.05 mg in 200 μl of paraffin oil (0.05 >p >0.01).


Low-Energy Antiphase Boundaries, Degenerate Superstructures, And Phase Stability In Frustrated Fcc Ising Model And Ag-Au Alloys, Nikolai A. Zarkevich, Teck L. Tan, Lin-Lin Wang, Duane D. Johnson Apr 2008

Low-Energy Antiphase Boundaries, Degenerate Superstructures, And Phase Stability In Frustrated Fcc Ising Model And Ag-Au Alloys, Nikolai A. Zarkevich, Teck L. Tan, Lin-Lin Wang, Duane D. Johnson

Duane D. Johnson

An Ising model exhibits zero-energy antiphase boundaries (APBs) and frustration on close-packed face-centered cubic (fcc) and triangular lattices. The frustration results in degenerate structures and chains of long-period superstructures forming a quasicontinuous ground-state “hull” in the formation energy versus composition (c) diagram. In alloys, a nonzero but small APB energy yields a c-dependent reduction in this degeneracy that affects the phase diagram topology and range of the two-phase coexistence. Using density functional theory combined with cluster expansions (CEs), we study Ag-Au alloys as a prototype and find the effective cluster interactions (dominated by nearest-neighbor pairs), predict energetics of millions of …


Modeling The Effects Of Value-Added Processing And Logistics Using Arena, Kurt A. Rosentrater, Elif Kongar Mar 2008

Modeling The Effects Of Value-Added Processing And Logistics Using Arena, Kurt A. Rosentrater, Elif Kongar

Kurt A. Rosentrater

Scarcity and cost of nonrenewable fossil fuels have been a growing focus of many energy-dependent nations, including the U.S., for the past couple of decades. There are mainly two ways to approach these problems: (1) reducing the energy dependency and/or (2) developing alternative means of energy production. Utilizing biofuels, which are renewable sources of energy, is a promising way to produce energy. But, as this industry grows, so too does the quantity of byproducts, which are known as DDGS. This paper discusses a model that has been developed to analyze the economic viability of DDGS processing, and includes both deterministic …


Three-Dimensional Data Merging Using Holoimage, Song Zhang, Shing-Tung Yau Mar 2008

Three-Dimensional Data Merging Using Holoimage, Song Zhang, Shing-Tung Yau

Song Zhang

Three-dimensional data merging is vital for full-field three-dimensional (3D) shape measurement. All 3D range data patches, acquired from either different sensors or the same sensor in different viewing angles, have to be merged into a single piece to facilitate future data analysis. A novel method for 3D data merging using Holoimage is proposed. Similar to the 3D shape measurement system using a phase-shifting method, Holoimage is a phase-shifting–based computer synthesized fringe image. The 3D information is retrieved from Holoimage using a phase-shifting method. If two patches of 3D data with overlapping areas are rendered by OpenGL, the overlapping areas are …


Grain Growth And Texture Development In Lithium Fluoride Thin Films, Hakkwan Kim, Alexander H. King Feb 2008

Grain Growth And Texture Development In Lithium Fluoride Thin Films, Hakkwan Kim, Alexander H. King

Alexander H. King

We have studied grain-growth and texture development in polycrystalline lithium fluoride thin films using dark-field transmission electron microscopy. We demonstrate that we can isolate the size distribution of 〈111〉 surface normal grains from the overall size distribution, based on simple and plausible assumptions about the texture. The {111} texture formation and surface morphology were also observed by x-ray diffraction and atomic force microscopy, respectively. The grain-size distributions become clearly bimodal as the annealing time increases, and we deduce that the short-time size distributions are also a sum of two overlapping peaks. The smaller grain-size peak in the distribution corresponds to …


Predicting Enthalpies Of Molecular Substances: Application To Libh4, Nikolai A. Zarkevich, Duane D. Johnson Feb 2008

Predicting Enthalpies Of Molecular Substances: Application To Libh4, Nikolai A. Zarkevich, Duane D. Johnson

Duane D. Johnson

For molecular substances exhibiting harmonic and nonharmonic vibrations, we present a first-principles approach to predict enthalpy differences between phases at finite temperatures, including solid-solid and melting. We apply it to the complex hydride LiBH4. Using ab initio molecular dynamics, we predict a structure for the high-T solid phase of lithium borohydride, and we propose an approximation to account for nonharmonic vibrations. We then predict the enthalpy changes for solid-solid transition, melting, and an H-storage reaction, all in agreement with experiment.


Three-Dimensional Shape Measurement Using A Structured Light System With Dual Cameras, Song Zhang, Shing-Tung Yau Jan 2008

Three-Dimensional Shape Measurement Using A Structured Light System With Dual Cameras, Song Zhang, Shing-Tung Yau

Song Zhang

A structured light system for three-dimensional shape measurement with single camera has the shortcoming of camera occlusion. To alleviate this problem, this paper introduces a structured light system with dual cameras for three-dimensional shape measurement. We discuss (1) system description, (2) system calibration, (3) three-dimensional data registration using the iterative closest-point (ICP) algorithm, and (4) three-dimensional data merging using holoimage. The principle of the system is introduced, and experiments are presented to verify its performance.


Application Of Genomics To Regulatory Ecological Risk Assessments For Pesticides, Steven P. Bradbury, Sigmund J. Degitz, Robert A. Hoke, Richard Brennan, Lee Ferguson, Rebecca Klaper, Laszlo Orban, David Spurgeon, Susan Tilton Jan 2008

Application Of Genomics To Regulatory Ecological Risk Assessments For Pesticides, Steven P. Bradbury, Sigmund J. Degitz, Robert A. Hoke, Richard Brennan, Lee Ferguson, Rebecca Klaper, Laszlo Orban, David Spurgeon, Susan Tilton

Steven P. Bradbury

Substantial advances in human health and ecological risk assessment have been achieved by the risk assessment community; however, challenges remain, such as providing credible scientific information on a timely, efficient basis to support decisions for industrial chemicals and pesticides. Current risk assessment data generation requirements-including animal welfare concerns and the volume, appropriateness, and cost of required data-and the large number of chemicals requiring evaluation are a challenge confronting the chemical industry, national and international regulatory agencies, and associated stakeholders (Bradbury et al. 2004). The lack of hazard data for many chemicals and the need to improve the efficiency and quality …


Toxic Responses Of The Fish Nervous System, Steven P. Bradbury, Richard W. Carlson, Tala R. Henry, Stephanie Padilla, John Cowden Jan 2008

Toxic Responses Of The Fish Nervous System, Steven P. Bradbury, Richard W. Carlson, Tala R. Henry, Stephanie Padilla, John Cowden

Steven P. Bradbury

Few of the approximately 70,000 chemicals on the Toxic Substances Control Act inventory or the 1000 to 1600 new chemicals introduced each year in the United States have been tested for neurotoxicity to support risk assessments (NRC, 1992), even though it is estimated that 5 to 10% of them are likely to be neurotoxic. Neurotoxicity has been defined as adverse effects of physical, biological, or chemical agents on the structure or function of the nervous system in developing or adult organisms (Philbert et al., 2000). From a human health risk assessment perspective, the potential for neurotoxic effects associated with synthetic …


Near-Monodisperse Ni−Cu Bimetallic Nanocrystals Of Variable Composition: Controlled Synthesis And Catalytic Activity For H2 Generation, Yawen Zhang, Wenyu Huang, Susan E. Habas, John N. Kuhn, Michael E. Grass, Yusuke Yamada, Peidong Yang, Gabor A. Somorjai Jan 2008

Near-Monodisperse Ni−Cu Bimetallic Nanocrystals Of Variable Composition: Controlled Synthesis And Catalytic Activity For H2 Generation, Yawen Zhang, Wenyu Huang, Susan E. Habas, John N. Kuhn, Michael E. Grass, Yusuke Yamada, Peidong Yang, Gabor A. Somorjai

Wenyu Huang

Near-monodisperse Ni1−xCux (x = 0.2−0.8) bimetallic nanocrystals were synthesized by a one-pot thermolysis approach in oleylamine/1-octadecene, using metal acetylacetonates as precursors. The nanocrystals form large-area 2D superlattices, and display a catalytic synergistic effect in the hydrolysis of NaBH4 to generate H2 at x = 0.5 in a strongly basic medium. The Ni0.5Cu0.5 nanocrystals show the lowest activation energy, and also exhibit the highest H2 generation rate at 298 K.


Compensation Effect Of Benzene Hydrogenation On Pt(111) And Pt(100) Analyzed By The Selective Energy Transfer Model, Kaitlin M. Bratlie, Yimin Li, Ragnar Larsson, Gabor A. Somorjai Jan 2008

Compensation Effect Of Benzene Hydrogenation On Pt(111) And Pt(100) Analyzed By The Selective Energy Transfer Model, Kaitlin M. Bratlie, Yimin Li, Ragnar Larsson, Gabor A. Somorjai

Kaitlin M. Bratlie

Kinetic measurements at low temperatures (310-360 K) using gas chromatography (GC) for benzene hydrogenation on Pt(100) and Pt(111) single crystal surfaces have been carried out at Torr pressures. These kinetic measurements demonstrated a linear compensation effect for the production of cyclohexane. A detailed application of the model of selective energy transfer to the experimentally obtained results yields the vibrational frequency of the adsorbate leading to reaction. This frequency is attributed to ring distortion modes. The vibrational frequency of the heat bath, or catalyst, is ascribed to a Pt-H mode. An approximate heat of adsorption of the reacting molecule is also …


Measuring The Dynamic Surface Accessibility Of Rna With The Small Paramagnetic Molecule Tempol, Vincenzo Venditti, Neri Niccolai, Samuel E. Butcher Jan 2008

Measuring The Dynamic Surface Accessibility Of Rna With The Small Paramagnetic Molecule Tempol, Vincenzo Venditti, Neri Niccolai, Samuel E. Butcher

Vincenzo Venditti

The surface accessibility of macromolecules plays a key role in modulating molecular recognition events. RNA is a complex and dynamic molecule involved in many aspects of gene expression. However, there are few experimental methods available to measure the accessible surface of RNA. Here, we investigate the accessible surface of RNA using NMR and the small paramagnetic molecule TEMPOL. We investigated two RNAs with known structures, one that is extremely stable and one that is dynamic. For helical regions, the TEMPOL probing data correlate well with the predicted RNA surface, and the method is able to distinguish subtle variations in atom …


Structure Sensitivity Of Carbon−Nitrogen Ring Opening: Impact Of Platinum Particle Size From Below 1 To 5 Nm Upon Pyrrole Hydrogenation Product Selectivity Over Monodisperse Platinum Nanoparticles Loaded Onto Mesoporous Silica, John N. Kuhn, Wenyu Huang, Chia-Kuang Tsung, Yawen Zhang, Gabor A. Somorjai Jan 2008

Structure Sensitivity Of Carbon−Nitrogen Ring Opening: Impact Of Platinum Particle Size From Below 1 To 5 Nm Upon Pyrrole Hydrogenation Product Selectivity Over Monodisperse Platinum Nanoparticles Loaded Onto Mesoporous Silica, John N. Kuhn, Wenyu Huang, Chia-Kuang Tsung, Yawen Zhang, Gabor A. Somorjai

Wenyu Huang

Well-defined platinum nanoparticles between 0.8 and 5.0 nm were prepared using dendrimer and polymer capping agents and supported onto mesoporous SBA-15 silica. Using these model catalysts, pyrrole hydrogenation was demonstrated to be structure sensitive because ring opening occurred more easily over larger particles compared to smaller ones. The phenomenon is caused by surface roughness or electronic effects that change with particle size.


Automatic Identification Of Discourse Moves In Scientific Article Introductions, Elena Cotos, Nick Pendar Jan 2008

Automatic Identification Of Discourse Moves In Scientific Article Introductions, Elena Cotos, Nick Pendar

Elena Cotos

This paper reports on the first stage of building an educational tool for international graduate students to improve their academic writing skills. Taking a text-categorization approach, we experimented with several models to automatically classify sentences in research article introductions into one of three rhetorical moves. The paper begins by situating the project within the larger framework of intelligent computer-assisted language learning. It then presents the details of the study with very encouraging results. The paper then concludes by commenting on how the system may be improved and how the project is intended to be pursued and evaluated.


Dendrimer Templated Synthesis Of One Nanometer Rh And Pt Particles Supported On Mesoporous Silica: Catalytic Activity For Ethylene And Pyrrole Hydrogenation, Wenyu Huang, John N. Kuhn, Chia-Kuang Tsung, Yawen Zhang, Susan E. Habas, Peidong Yang, Gabor A. Somorrjai Jan 2008

Dendrimer Templated Synthesis Of One Nanometer Rh And Pt Particles Supported On Mesoporous Silica: Catalytic Activity For Ethylene And Pyrrole Hydrogenation, Wenyu Huang, John N. Kuhn, Chia-Kuang Tsung, Yawen Zhang, Susan E. Habas, Peidong Yang, Gabor A. Somorrjai

Wenyu Huang

Monodisperse rhodium (Rh) and platinum (Pt) nanoparticles as small as ∼1 nm were synthesized within a fourth generation polyaminoamide (PAMAM) dendrimer, a hyperbranched polymer, in aqueous solution and immobilized by depositing onto a high-surface-area SBA-15 mesoporous support. X-ray photoelectron spectroscopy indicated that the as-synthesized Rh and Pt nanoparticles were mostly oxidized. Catalytic activity of the SBA-15 supported Rh and Pt nanoparticles was studied with ethylene hydrogenation at 273 and 293 K in 10 torr of ethylene and 100 torr of H2 after reduction (76 torr of H2 mixed with 690 torr of He) at different temperatures. Catalysts were active without …


Highly Selective Synthesis Of Catalytically Active Monodisperse Rhodium Nanocubes, Yawen Zhang, Michael E. Grass, John N. Kuhn, Feng Tao, Susan E. Habas, Wenyu Huang, Peidong Yang, Gabor A. Somorjai Jan 2008

Highly Selective Synthesis Of Catalytically Active Monodisperse Rhodium Nanocubes, Yawen Zhang, Michael E. Grass, John N. Kuhn, Feng Tao, Susan E. Habas, Wenyu Huang, Peidong Yang, Gabor A. Somorjai

Wenyu Huang

Monodisperse sub-10 nm Rh nanocubes were synthesized with high selectivity (>85%) by a seedless polyol method. The {100} faces of the Rh NCs were effectively stabilized by chemically adsorbed Br− ions from trimethyl(tetradecyl)ammonium bromide (TTAB). This simple one-step polyol route can be readily applied to the preparation of Pt and Pd nanocubes. Moreover, the organic molecules of PVP and TTAB that encapsulated the Rh nanocubes did not prevent catalytic activity for pyrrole hydrogenation and CO oxidation.


Influence Of Reaction With Xef2 On Surface Adhesion Of Al And Al2o3 Surfaces, Tianfu Zhang, Jeong Park, Wenyu Huang, Gabor A. Somoraji Jan 2008

Influence Of Reaction With Xef2 On Surface Adhesion Of Al And Al2o3 Surfaces, Tianfu Zhang, Jeong Park, Wenyu Huang, Gabor A. Somoraji

Wenyu Huang

The change in surfaceadhesion after fluorination of Al and Al2O3surfaces using XeF2 was investigated with atomic force microscopy. The chemical interaction between XeF2 and Al and Al2O3surfaces was studied by in situx-ray photoelectron spectroscopy. Fresh Al and Al2O3surfaces were obtained by etching top silicon layers of Si∕Al and Si∕Al2O3 with XeF2. The surfaceadhesion and chemical composition were measured after the exposure to air or annealing (at 200°C under vacuum). The correlation between the adhesion force increase and presence of AlF3 on the surface was revealed.


Time-Resolved Investigation Of The Acoustic Vibration Of A Single Gold Nanoprism Pair, J. Burgin, P. Langot, N. Del Fatti, F. Vallee, Wenyu Huang, M.A. El-Sayed Jan 2008

Time-Resolved Investigation Of The Acoustic Vibration Of A Single Gold Nanoprism Pair, J. Burgin, P. Langot, N. Del Fatti, F. Vallee, Wenyu Huang, M.A. El-Sayed

Wenyu Huang

The acoustic vibration of single gold nanoprism pairs on a glass substrate has been investigated in the time-domain combining a spatial modulation spectroscopy microscope with a high-sensitivity femtosecond pump−probe setup. Three modes were observed and ascribed to two in-plane and one out-of-plane vibration of the nanoprisms forming the pair, in agreement with a theoretical analysis. The periods of the two former modes with similar nature show weak (about 10%) and well correlated pair to pair fluctuations that can be unambiguously ascribed to variation of the prism geometry. In contrast, strong fluctuations, by almost a factor of 6, of the mode …


Sub-Two Nanometer Single Crystal Au Nanowires, Ziyang Huo, Chia-Kuang Tsung, Wenyu Huang, Xiaofeng Zhang, Peidong Yang Jan 2008

Sub-Two Nanometer Single Crystal Au Nanowires, Ziyang Huo, Chia-Kuang Tsung, Wenyu Huang, Xiaofeng Zhang, Peidong Yang

Wenyu Huang

Ultrathin single crystal Au nanowires with diameter of ∼1.6 nm and length of few micrometers were synthesized with high yield by simply mixing HAuCl4 and oleylamine at room temperature. High resolution transmission electron microscopy studies revealed that all of these nanowires are single crystalline and grew along the [111] direction. The valency evolution of the gold species during the synthesis was studied by X-ray photoelectron spectroscopy, which showed a clear Au3+ → Au+ → Au stepwise reduction at different reaction stages. Small angle X-ray scattering and small-angle X-ray diffraction suggest mesostructure formation upon HAuCl4 and oleylamine mixing. The slow in …


A Reactive Oxide Overlayer On Rhodium Nanoparticles During Co Oxidation And Its Size Dependence Studied By In Situ Ambient-Pressure X-Ray Photoelectron Spectroscopy, Michael E. Grass, Hendrik Bluhm, Yawen Zhang, Derek Butcher, Jeong Y. Park, Yimin Li, Kaitlin M. Bratlie, Tianfu Zhang, Gabor A. Somorjai Jan 2008

A Reactive Oxide Overlayer On Rhodium Nanoparticles During Co Oxidation And Its Size Dependence Studied By In Situ Ambient-Pressure X-Ray Photoelectron Spectroscopy, Michael E. Grass, Hendrik Bluhm, Yawen Zhang, Derek Butcher, Jeong Y. Park, Yimin Li, Kaitlin M. Bratlie, Tianfu Zhang, Gabor A. Somorjai

Kaitlin M. Bratlie

The smaller, the better: In situ synchrotron ambient pressure X-ray photoelectron spectroscopy allows examination of the oxidation state of the surface of the rhodium nanoparticles (NPs) during CO oxidation in an O2 atmosphere. 2 nm NPs oxidize to a larger extent than 7 nm NPs during reaction at 150-200°C, which correlates with a fivefold increase in turnover frequency for the smaller nanoparticles.


Long-Term Tillage Frequency Effects On Dryland Soil Physical And Hydraulic Properties, Andrew W. Lenssen, J. D. Jabro, U. M. Sainju, W. B. Stevens, R. G. Evans Jan 2008

Long-Term Tillage Frequency Effects On Dryland Soil Physical And Hydraulic Properties, Andrew W. Lenssen, J. D. Jabro, U. M. Sainju, W. B. Stevens, R. G. Evans

Andrew W. Lenssen

Soil tillage is considered one of most important practices in agricultural production due to its influence on physical, chemical, and biological properties of the soil environment. The effect of a long-term tillage [no-till (NT), spring till (ST), and fall and spring till (FST)] was investigated on soil penetration resistance (PR), bulk density (BD), gravimetric water content (GWC) and saturated hydraulic conductivity (Ks) under dryland conditions. Tillage effects on these physical properties were tested after 22 years on a Dooley sandy loam (fine-loamy, mixed Typic Argiborolls) derived from glacial till parent material. The statistical design used was a randomized complete block …


Absolute Phase-Assisted Three-Dimensional Data Registration For A Dual-Camera Structured Light System, Song Zhang, Shing-Tung Yau Jan 2008

Absolute Phase-Assisted Three-Dimensional Data Registration For A Dual-Camera Structured Light System, Song Zhang, Shing-Tung Yau

Song Zhang

For a three-dimensional shape measurement system with a single projector and multiple cameras, registering patches from different cameras is crucial. Registration usually involves a complicated and time-consuming procedure. We propose a new method that can robustly match different patches via absolute phase without significantly increasing its cost. For y and z coordinates, the transformations from one camera to the other are approximated as third-order polynomial functions of the absolute phase. The x coordinates involve only translations and scalings. These functions are calibrated and only need to be determined once. Experiments demonstrated that the alignment error is within RMS 0.7 mm …


Attachment Of Bacterial Indicators To Particulates In Runoff From Various Soils, Michelle L. Soupir, Saied Mostaghimi Jan 2008

Attachment Of Bacterial Indicators To Particulates In Runoff From Various Soils, Michelle L. Soupir, Saied Mostaghimi

Michelle L. Soupir

A field study was conducted to examine the fate of E. coli and enterococci transport from three bare soil types receiving cowpat treatments and develop relationships between bacterial partitioning and phosphorous and carbon transport. Particles sizes to which cells preferentially associated were also identified.