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A New Method For Preparing Self-Assembled Lipid Bilayers On Pt Electrode, Peng Diao, Dian-Lu Jiang, Xiao-Li Cui, Deng-Ping Gu, Ru-Ting Tong

Journal of Electrochemistry

A new method for preparing Pt-supported bilayer lipid membrane (Pt-BLM) on Pt electrode cleaned by high power ultrasound was reported. The reported method was convenient, costing less platinum and could be used to form large-area Pt-BLM as compared with the traditional Pt-wire-cutting method. The electrical properties of Pt-BLM were studied using electrochemical impedance spectroscopy and cyclic voltammetry. Experimental results showed that the values of membrane capacitance and the voltammetric characteristics were consistent with those of Pt-BLM prepared by traditional method.

Direct Electrolysis Of Seawater On Conducting Film For Microbial Anticorrosion 1. Simulation And Measurement Technique, Wei-Ling Hu, Ling-Ling Wu, Jing Zhou, Jing-Xin Li, Jin Luo, Zhong-Hua Lin

Journal of Electrochemistry

Based on the electrochemical micro probe and the weak signal detection technique, simulated test and measurement system were set up by the use of four-electrode cell(including a micro electrode), bipotentiostat, lock-in amplifier and three-dimensional micro manipulating device. Based on the system, the micrometer scale concentration distribution of trace hypochlorite, which is produced by direct electrolysis of seawater on the conducting film for preventing microbial corrosion has been obtained for the first time. Both relationships between concentration of hypochlorite and its reduction current, which is termed an working curve, and between the reduction current of hypochlorite and measured time are reported.

Spectroellipsometric Studies On Electrochemistry And Its Application, Zong-Qing Huang, Sheng-Tao Zhang, Shang-Fen Xie, Chang-Guo Chen, Yu-Ru Yang, Wei Zhu

Journal of Electrochemistry

Ellipsometric measurements are often extremely sensitive to the presence of very thin surface layers,to changes in their thickness (or coverage), and to changes in surface topography at an atomic scale. These characteristics make the use of ellipsometry for electrochemical studies particularly attractive. The ellipsometric studies on electrochemistry and its applications carried out in the Electrochemical Laboratory of Chongqing University are reviewed briefly: 1)The studies on electrochemistry of classical ellipsometry. 2)The new function V_op suggested by the authors. 3)The applications of new approcaches with new function V_op suggested by the authors.

Mathematical Modelling Of Extracellular Matrix Dynamics Using Discrete Cells: Fiber Orientation And Tissue Regeneration, J. C. Dallon, J. A. Sherratt, P. K. Maini

Faculty Publications

Matrix orientation plays a crucial role in determining the severity of scar tissue after dermal wounding. We present a model framework which allows us to examine the interaction of many of the factors involved in orientation and alignment. Within this framework, cells are considered as discrete objects, while the matrix is modeled as a continuum. Using numerical simulations, we investigate the effect on alignment of changing cell properties and of varying cell interactions with collagen and fibrin.

The Galactic Center Isolated Nonthermal Filaments As Analogs Of Cometary Plasma Tails, Steven N. Shore, Ted La Rosa

Faculty Articles

We propose a model for the origin of the isolated nonthermal filaments observed at the Galactic center based on an analogy to cometary plasma tails. We invoke the interaction between a large-scale magnetized galactic wind and embedded molecular clouds. As the advected wind magnetic field encounters a dense molecular cloud, it is impeded and drapes around the cloud, ultimately forming a current sheet in the wake. This draped held is further stretched by the wind flow into a long, thin filament the aspect ratio of which is determined by the balance between the dynamical wind and amplified magnetic field pressures. …

Assignment Of The Infrared Spectra Of The Methanol Trimer, Gregory S. Tschumper, Jason M. Gonzales, Henry F. Schaefer

Chemistry Faculty Research & Creative Works

Second-order Möller-Plesset perturbation theory (MP2) and density functional theory (DFT) were employed to optimize two cyclic conformations of the methanol trimer, denoted "bowl" and "chair," as well as a third noncyclic, "open-chain" conformation. This is the first time all three methanol trimer conformations have been studied at the same level of theory. Harmonic vibrational frequencies confirm that all stationary points are minima on the intermolecular potential energy hypersurface. The chair is consistently predicted to be the most stable conformer. The bowl and open-chain conformers are only slightly less stable and lie within 3 kcal/mol. Results indicate that the bowl structure …

1H Nmr Studies On The Cua Center Of Nitrous Oxide Reductase From Pseudomonas Stutzeri, Richard C. Holz, Marcela L. Alvarez, Walter G. Zumft, David M. Dooley

Chemistry Faculty Research and Publications

¹H NMR spectra of the Cu_A center of N₂OR from Pseudomonas stutzeri, and a mutant enzyme that contains only Cu_A, were recorded in both H₂O- and D₂O-buffered solution at pH 7.5. Several sharp, well-resolved hyperfine-shifted ¹H NMR signals were observed in the 60 to −10 ppm chemical shift range. Comparison of the native and mutant N₂OR spectra recorded in H₂O-buffered solutions indicated that several additional signals are present in the native protein spectrum. These signals are attributed to a dinuclear copper(II) center. At least …

Some Notions Of Complex Adaptive Systems And Their Relationship To Our World, Jens G. Pohl

Collaborative Agent Design (CAD) Research Center

This paper assumes that the world we live in consists of many interwoven complex adaptive systems. In the literature such systems are characterized as comprising many moving parts and processes that interact significantly in a mostly non-linear manner. It is argued that the forces that act on such complex systems are not additive, and that their impact occurs along non-linear interactions within the system. In particular, many of these systems are adaptive in that they change their behavior (through their interactions) over time, so that if they are subjected to a similar force or event a second time they …

Cavefish Population Status And Environmental Quality In Cave Springs Cave, Arkansas - Final Report Submitted To Arkansas Natural Heritage Commission, G. O. Graening, Arthur V. Brown

Arkansas Water Resources Center Technical Reports

This report summarizes the continuing effort to monitor environmental quality in the Cave Springs Cave Natural Area and to implement the Ozark Cavefish Recovery Plan. Last year’s report (Brown et al., 1998) identified certain environmental stressors, including a trend over 15 years of increasing nutrient pollution, a low cavefish population count of only 106, and the presence of heavy metals in the cave water and one semi-volatile organic compound (the phthalate DEHP at 500 ppb) in resident crayfish tissue. This year’s monitoring effort demonstrates that fecal coliforms continue to exceed Arkansas State Water Quality Standards (Regulation 2), sometimes by a …

Induced Changes In Solvent Structure By Phospholipid Monolayer Formation At A Liquid–Liquid Interface, R. A. Walker, D. E. Gragson, G. L. Richmond

Chemistry and Biochemistry

Vibrational sum frequency spectroscopy has been used in conjunction with dynamic surface tension measurements to study formation of a 1,2-dilauroyl-sn-phosphatidylcholine (DLPC) monolayer at a water–carbon tetrachloride interface. Surface tension measurements show that an aqueous solution of liquid crystalline phosphocholine vesicles (4.5 μM DLPC) requires several hours to form a tightly packed, fully equilibrated monolayer of DLPC monomers. Vibrational spectra of the interfacial region at different stages in the monolayer formation process indicate that the solvent structure undergoes dramatic re-organization as the monolayer forms. Initial adsorption of DLPC monomers severely disrupts the interfacial hydrogen bonding. Intensity in the OH …

Analysis Of Galvanized Steel Plates Using Glow Discharge-Atomic Emission Spectrometry, Liang Wang

Masters Theses & Specialist Projects

Combining an intense emission source and a high-speed sputtering source in one, glow discharge atomic emission spectrometer (GD-AES) provides an efficient technique for analyzing surfaces, coatings and bulk solids. The purpose of our work is to explore the optimum lamp operation parameters of SA-2000 for analysis of galvanized steel plate and to investigate the method for qualitatively and quantitatively analyzing the zinc coating. Under the optimum experimental conditions found in our study, which are current of 19-21 mA; voltage of 900-1200 V; pressure 2.0-2.5 torr, the calibration curve is constructed, so that specific zinc concentration can be assign to the …

Comparison Of An Advanced Mercury Analyzer With The Cold Vapor Atomic Absorption Technique For The Determination Of Mercury In Coal, Dong Li

Masters Theses & Specialist Projects

For over 30 years the industry standard method for mercury analysis has been the cold vapor atomic absorption spectrometric technique (CVAAS). Recent developments in improving this technique have focused on procedures for concentrating mercury in the analyte or materials to improve detection. The LECO Corporation produces an Advanced Mercury Analyzer, the AMA-254, for analysis of the solid and liquid samples. The system allows for the thermal heating of the sample to decompose the sample and release mercury, which is concentrated in a gold amalgam. Thermal desorption of the mercury from the amalgam is detected by atomic absorption spectroscopy. A comparison …

The Effects Of Phosphorus Enrichment On The Dominant Phytoplankton Communities Of Chaney Lake, Kathy Tehrani

Masters Theses & Specialist Projects

Chaney Lake is a temporary karst wetland located in southern Warren County, Kentucky. Because of an impermeable chert layer between the surface and the porous limestone, Chaney Lake fills with water over the winter and spring and then gradually drains over the summer. Three experiments were conducted over the course of the 1998 flooding season to assess the effects of phosphorus addition on the phytoplankton community in Chaney Lake. Ten plastic-sided mesocosms were constructed and placed in the marsh area of the wetland at three different periods: early spring, early summer, and late summer. Phosphorus in the form of K2HPO4 …

Fisheries Research Report No. 114 - The Western Australian Scallop Industry, D C. Harris, L M. Joll, R A. Watson

Fisheries Research Reports

Five separate commercial fisheries target the saucer scallop, Amusium balloti (Bernadi 1861) in Western Australian waters. While the average annual catch from these fisheries is around 600 tonnes of scallop meat, past catches have been highly variable with annual landings ranging from 150 to 4,400 tonnes of meat worth between $2 and $59 million. Consequently, scallops represent one of the larger single-species fisheries operating in Western Australia (WA).

A. balloti has a distribution spanning most of the WA coast, from Broome in the north around to Esperance in the south. Despite this extensive distribution, saucer scallops tend to be restricted …

Fisheries Research Report No. 115 - Statistical Analysis Of Gascoyne Region Recreational Fishing Study July 1996, Neil R. Sumner, Richard A. Steckis

Fisheries Research Reports

A survey of recreational fishers in the Gascoyne region of Western Australia was conducted in July 1996 to provide information required by fisheries managers. Catch rates, attitudinal, demographic and economic information from boat-based and shore-based fishers was collected by Fisheries Officers. Pink snapper (Pagrus auratus) was the primary species caught by boatbased recreational fishers in the region. Various species of whiting were the predominant catch from shore-based anglers. Most fishers interviewed (80%) supported the introduction of an upper limit on the amount of fish and fillets that a person could take away from the Gascoyne region for personal or family …

Low Temperature And Cold Drought Risks In Crop Production In Temperate Kashmir, Badrul Hasan, Ashok Kumar, A. A. Khan

Drought Network News (1994–2001)

Temperature plays a vital role in life processes and crop production. Physical and chemical processes within plants are temperature dependent; these processes in turn control biological reactions in crop plants. Temperature also plays a significant role in some aspects of crop physiological cycles: the diffusion rate of gases and liquids changes with temperature; the solubility of substances is temperature dependent; rapid progress occurs as a result of temperature increases; and the equilibrium and stability of various systems and compounds (including enzymes) is a function of temperature.

Air temperature at the screen level is one of the most important variables affecting …

Summer 1999, Nsu Oceanographic Center

Currents

No abstract provided.

Folding Dynamics Of Single Gcn-4 Peptides By Fluorescence Resonant Energy Transfer Confocal Microscopy, Yiwei Jia, David Talaga, Wai Leung Lau, Helen S.M. Lu, William F. Degrado, Robin M. Hochstrasser

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

We have prepared a bichromophoric crosslinked variant of GCN4-P1 for single-molecule fluorescence energy transfer experiments (GCN4-Pf). The folding and unfolding fluctuations of single GCN4-Pf molecules are measured in a two-channel confocal microscope with which donor and acceptor fluorescence trajectories are measured simultaneously. The energy transfer efficiency is thereby determined and its probability distributions as a function of added denaturant [urea] are calculated. The distributions indicate that single molecule GCN4-Pf is in dynamic folding equilibrium with the position of the equilibrium being altered by the concentration of urea.

41st Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 41st annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-sponsored by the Colorado Section of the American Chemical Society and the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, August 1-5, 1999.

Morphology Of Wetland Streams, Michael C. Jurmu

All-Inclusive List of Electronic Theses and Dissertations

Recent understanding and concern with wetland environments has resulted in an increase in restoration and creation projects aimed at replicating these ecosystems. The unique characteristics within wetland environments result in different controls on streams traversing these areas, yet little research has been conducted to determine whether the morphology of these streams differs from streams in non-wetland, alluvial environments. Wetland streams from three different physiographic regions of the U.S. are compared to four morphological models and 12 additional features cited as typical in non-wetland streams. Analysis of this comparison will aid in determining whether wetland streams have differing morphology and which …

The Probe, Issue 203 – August 1999

The Probe: Newsletter of the National Animal Damage Control Association

Trappers Association Challenges Ballot Initiatives
Troubling Horizon for NADCA -- Robert H. Schmidt, President
Reed-Joseph International recently announced the availability of CAPA long range pyrotechnic cartridges.
Hazards of Deer Relocation: Mixed Success
Book Review : "Conibear Beaver Trapping in Open Water" by Wesley Murphey. Lost Creek Books, Eugene, Oregon, 1996. 109 pp. Illustrated. ($14.00 postpaid)
Eastern Black Bear Workshop Held in Massachusetts

Water Current, Volume 31, No. 4, August 1999

Water Current Newsletter

From Buffalo to Bottled Water, Summer Water Tour Attracts Newcomers
From the Director: Nebraska's Number One Resource? You Be the Judge
1999 Nebraska Water Legislation
Seventh Annual Festival of Color Will be August 28, Near Mead
Two Join Water Sciences Lab Staff
Water News Briefs
Overview of Vision Statements Available
The Value of Water
1999 USBR Hydrologic Modeling Inventory (HMI)
Understanding and Addressing Groundwater Risks
Water Center Faculty Responds to Request from "Down Under"

A Note On The Aymptotic Behavior Of The Heights In B-Tries For B Large, Charles Knessl, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.

Modeling Macrophytes Of The Columbia Slough, Oregon, Chris Berger, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The Columbia Slough is a tidally influenced freshwater system of wetlands, channels, and lakes located within the Portland, Oregon metropolitan area at the confluence of the Willamette and Columbia Rivers. It is a eutrophic water body susceptible to algae blooms and crashes and periods of high pH which violate water quality standards. High nutrient loads from groundwater principally controls algae productivity. Past structural changes to the Columbia Slough have included filling of wetlands and lakes and the construction of levees, dikes, culverts and irrigation channels. These changes have altered the natural flow dynamics creating an environment more conducive to eutrophication. …

Inhibition Of The Aminopeptidase From Aeromonas Proteolytica By Aliphatic Alcohols. Characterization Of The Hydrophobic Substrate Recognition Site, Leila Ustynyuk, Brian Bennett, Tanya Edwards, Richard C. Holz

Physics Faculty Research and Publications

Seven aliphatic and two aromatic alcohols were tested as reporters of the substrate selectivity of the aminopeptidase from Aeromonas proteolytica (AAP). This series of alcohols was chosen to systematically probe the effect of carbon chain length, steric bulk, and inhibitor shape on the inhibition of AAP. Initially, however, the question of whether AAP is denatured in the presence of aliphatic alcohols was addressed. On the basis of circular dichroism (CD), electronic absorption, and fluorescence spectra, the secondary structure of AAP, with and without added aliphatic alcohols, was unchanged. These data clearly indicate that AAP is not denatured in aliphatic alcohols, …

Avian Communities Of Large Reclaimed Mine Grasslands In Southwestern Indiana, Travis L. Devault

All-Inclusive List of Electronic Theses and Dissertations

Many bird species native to the tallgrnss prairie region oCthc central U.S. have declined drastically since European settlement due lo the destruction and alteration of grassland habitat. In this study, the breeding bird communities or 21 large reclaimed surface coal mine grasslands in a seven-county area or southwestern Indiana were examined with respect to species and guild composition, density, variation among sites, and grassland size. In addition, the vegetation characteristics of nine large mine grasslands were described and related to the presence and abundance or eight grasslund bird species common to the study areas. The immense size of mine grasslands …

The Prairie Naturalist Volume 31, No.3 September 1999

The Prairie Naturalist

HANTA VIRUS INFECTION IN NORTH DAKOTA SMALL MAMMALS: 1994,1995 ▪ R. W. Seabloom, J. J. Feist, and S L. McDonough

AMERICAN WOODCOCK IN COLORADO ▪ C. E. Braun

AVIFAUNA OF AN EARLY SUCCESSIONAL HABITAT ALONG THE MIDDLE MISSOURI RIVER ▪ D. L. Swanson

REPRODUCTIVE STATUS OF FLEA BEETLES IN NORTH DAKOTA AND SOUTH DAKOTA ▪ M. A. Brinkman and S. A. Clay

NUTRIENT AND ENERGY CHARACTERISTICS OF INVERTEBRATES FROM TWO LOCATIONS IN KANSAS ▪ S. G. Papon, R. J. Robel, and K. Kemp

BOOK REVIEWS

The Wood Warblers ▪ M. G. Knutson

A Fascination With Birds. ▪ J. A. Dechant …

Maritime Pine For Western Australia - Revegetation On Farms Information Kit, David Bicknell, Department Of Conservation And Land Management

Natural resources published reports

Revegetation on farms

The Revegetation on Farms Project and the material in this Information Kit is targeted at the agricultural zone of Western Australia with less than 600 mm rainfall. Some of the information is valid outside this range.

All information is provided in good faith, to help make informed revegetation decisions leading to sustainable land use.

TreeNote No 20 - Weed control in eucalypts and pines

TreeNote No 21 - Insect pests of eucalypts and pines

In search of the perfect pine - David Gough (Article)

Farming carbon - Syd Shea (Article)

Rank-Order Of Potencies For Inhibition Of The Secretion Of Aβ40 And Aβ42 Suggests That Both Are Generated By A Single Γ-Secretase, John T. Durkin, Seetha Murthy, E. Jean Husten, Stephen P. Trusko, Mary J. Savage, David Rotella, Barry D. Greenberg, Robert Siman

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

The Alzheimer's disease amyloid peptide Aβ has a heterogeneous COOH terminus, as variants 40 and 42 residues long are found in neuritic plaques and are secreted constitutively by cultured cells. The proteolytic activity that liberates the Aβ COOH terminus from the β-amyloid precursor protein is called γ-secretase. It could be one protease with dual specificity or two distinct enzymes. By using enzyme-linked immunosorbent assays selective for Aβ40 or Aβ42, we have measured Aβ secretion by a HeLa cell line, and we have examined the dose responses for a panel of five structurally diverse γ- secretase inhibitors. The inhibitors lowered Aβ …

Protein Adducts Of Iso[4]Levuglandin E2, A Product Of The Isoprostane Pathway, In Oxidized Low Density Lipoprotein, Robert G. Salomon, Wei Sha, Cynthia Brame, Kamaljit Kaur, Ganesamoorthy Subbanagounder, June O'Neil, Henry F. Hoff, L. Jackson Roberts Ii

Pharmacy Faculty Articles and Research

Levuglandin (LG) E₂, a cytotoxic seco prostanoic acid co-generated with prostaglandins by nonenzymatic rearrangements of the cyclooxygenase-derived endoperoxide, prostaglandin H₂, avidly binds to proteins. That LGE₂-protein adducts can also be generated nonenzymatically is demonstrated by their production during free radical-induced oxidation of low density lipoprotein (LDL). Like oxidized LDL, LGE₂-LDL, but not native LDL, undergoes receptor-mediated uptake and impaired processing by macrophage cells. Since radical-induced lipid oxidation produces isomers of prostaglandins, isoprostanes (isoPs), via endoperoxide intermediates, we postulated previously that a similar family of LG isomers, isoLGs, is cogenerated with isoPs. Now …