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Full-Text Articles in Engineering

Modeling Technique For Optimal Recovery Of Immiscible Light Hydrocarbons As Free Product From Contaminated Aquifer, Grant S. Cooper Jr., Richard C. Peralta, Jagath J. Kaluarachchi Dec 1993

Modeling Technique For Optimal Recovery Of Immiscible Light Hydrocarbons As Free Product From Contaminated Aquifer, Grant S. Cooper Jr., Richard C. Peralta, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

Contamination sites associated with light non-aqueous phase liquids {LNAPL) are numerous and represent difficult cleanup problems. Remediation methods for cleanup of LNAPL fluids in subsurface systems are continuously evolving with the development of various technologies for pump.-and~treat, soil venting, and in-situ bioremediation. Evaluating the effectiveness of remediation techniques as well as attempting to improve their efficiency has been a focus of many researchers, These efforts have included the development of computer simulation models to predict and analyze the fluid movement, entrapment, and mobilization of three~phase systems in porous media. The capability of computer models that not only simulate but optimize …


S/O Modeling Technique For Optimal Containment Of Light Hydrocarbons In Contaminated Unconfined Aquifers, Grant S. Cooper Jr., Jagath J. Kaluarachchi, Richard C. Peralta Nov 1993

S/O Modeling Technique For Optimal Containment Of Light Hydrocarbons In Contaminated Unconfined Aquifers, Grant S. Cooper Jr., Jagath J. Kaluarachchi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

An innovative approach is presented to minimize pumping for immobilizing a floating plume of a light non-aqueous phase liquid (LNAPL). The best pumping strategy is determined to contain the free oil product and provide for gradient control of the water table. This approach combined detailed simulation, statistical analysis, and optimization. This modeling technique uses regression equations that describe system response to variable pumping stimuli. The regression equations were developed from analysis of systematically performed simulations of multiphase flow in an areal region of an unconfined aquifer. Simulations were performed using ARMOS, a finite element model. ARMOS can be used simulate …


The Spirit Iii Radiometer Data Compression System, Scott E. Budge Oct 1993

The Spirit Iii Radiometer Data Compression System, Scott E. Budge

Electrical and Computer Engineering Faculty Publications

In this paper, we describe the image data compressor designed and built for the SPIRIT III radiometer which will be used to provide a real-time "quick-look" capability for the instrument. A a brief description of elements of the radiometer design which determine the data compression requirements is given, followed by a description of the VQ-based hybrid data compression algorithm. Highlights of the hardware design are also discussed.

The performance of the compressor is presented. Tests made using data obtained during cold tests of the instrument indicate an RMS error of 6.26 counts for the 10:1 compression mode and 5.83 counts …


Review Of Planning Distribution Model (Pdm) Status And Application Possibilities For The Egyptian Irigation System, Robert W. Hill, Richard C. Peralta, Gary P. Merkley Sep 1993

Review Of Planning Distribution Model (Pdm) Status And Application Possibilities For The Egyptian Irigation System, Robert W. Hill, Richard C. Peralta, Gary P. Merkley

Civil and Environmental Engineering Faculty Publications

The comprehensive water management Planning Distribution Model, or PDM, was developed by the Biological and Irrigation Engineering Department, Utah State University (USU), under contract with the United States Bureau of Reclamation (USBR). Most of the work was carried out in the Planning Sector, Ministry of Public Works and Water Resources (MPWWR) , in Cairo, under the Planning Studies and Models Component of the USAID funded Irrigation Management Systems Project.


Optimal Contaminant Plume Management With Us/Wells, Alaa H. Aly, Richard C. Peralta Jul 1993

Optimal Contaminant Plume Management With Us/Wells, Alaa H. Aly, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

A micro-computer based software package developed at utah State University for computing optimal pumping strategies for well systems (US/WELLS) is demonstrated. US/WELLS is used to determine the optimal time-varying sequence of extraction and injection rates when only limited data is available. The software determines the extraction/injection rates, in pre-specified locations, needed for immobilizing and/or extracting a groundwater contaminant plume. In the optimization problem, the objective function can be either to minimize the extraction/injection rates needed {linear) or to minimize the hydraulic power used for lifting water (quadratic). In either case, different weights can be assigned to emphasize any time period. …


Optimizing Conjunctive Water Use In A Dynamic Stream Aquifer System, Getachew Belaineh, Richard C. Peralta Jul 1993

Optimizing Conjunctive Water Use In A Dynamic Stream Aquifer System, Getachew Belaineh, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Long-term water management planning models frequently use large time steps and must employ fairly crude assumptions (such as average climatic conditions, etc.). Managing stream aquifer systems during a dry season requires using finer discretization in time and space. Presented is a computer model, US/REMAX, developed by Utah State University personnel for aiding best management of stream-aquifer systems for both long and short eras. The model computes strategies for optimally allocating surface and ground water resources in time and space. For a water supply problem the model can maximize the sum of delivered surface and ground water. For an environmental protection …


Optimizing Irrigation Management For Pollution Control And Sustainable Crop Yield, G. R. Musharrafieh, Richard C. Peralta Jul 1993

Optimizing Irrigation Management For Pollution Control And Sustainable Crop Yield, G. R. Musharrafieh, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

We developed a simulation-optimization model which maximizes crop yield while maintaining target salt concentration in the root zone, and/ or preventing salt from leaching to the groundwater. The model performs nonlinear optimization and simulation. Implicit finite difference forms of the nonlinear, transient, unsaturated water flow equation, and the convection-diffusion equation are embedded as constraints. Other constraints include nonlinear functions describing the hydraulic properties of the medium. The objectives of the management model is to develop irrigation strategies which prevent salt leaching to the groundwater when salty irrigation water is used. Five different irrigation strategies are developed for Huntington Research Farm, …


A Generalized Data Conversion System, Kevan Morgan Jun 1993

A Generalized Data Conversion System, Kevan Morgan

Undergraduate Honors Capstone Projects

To assist in the processing of data files collected by the Space Dynamics Laboratory at Utah State University, the software project GENDACS has been completed. GENDACS, acronym for A Generalized Data Conversion System, will contribute to its research program.

Data are collected from various sensory instruments by the Computer Data Acquisition System. The instrument readings are brought in, tagged with the time they were taken, and stored on an optical disk in a compact, binary (non-ASCII) format. GENDACS is designed so that the program can read in such files, sort out the data, and convert them into a new ASCII …


Jet Velocity Dissipation And Modelling With Aeration, Stephen J. Schlenker May 1993

Jet Velocity Dissipation And Modelling With Aeration, Stephen J. Schlenker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of natural aeration and fall height upon velocity dissipation and modelling were studied. Underwater velocities and void ratios (proportion of air volume to total volume) were measured along the jet centerline at various depths in the receiving pool under 1- and 2-inch diameter vertical circular free-falling jets. Maximum air bubble penetration depths were also measured. In the tests, the nozzle velocities were designed so that the two differently sized models would have equivalent Froude numbers for direct comparison of respective underwater parameters. Air entrainment-the natural development of air bubbles within a pool receiving a free-falling jet-causes voids to …


Analysis Of Cutthroat Flume Discharge Ratings, Liyan Ren May 1993

Analysis Of Cutthroat Flume Discharge Ratings, Liyan Ren

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sixteeen sets of original laboratory data collected by many investigators for various Cutthroat flume sizes are thoroughly reviewed and organized. Best-fit discharge parameters are obtained by performing the free-flow analysis and the submerged-flow analysis. Then, the transition submergence can be calculated. Afterwards, the unified free-flow and submerged-flow discharge parameters are developed for each flume size in order to generalize the calibrations for Cutthroat flumes. This is a very tedious process requiring a trial-and-error approach. Finally, comparisons are made of the measured laboratory discharges with the predicted discharges for both free flow and submerged flow using both the best-fit and the …


A Mechanistic Approach To Modeling Habitat Needs Of Drift-Feeding Salmonids, R. Craig Addley May 1993

A Mechanistic Approach To Modeling Habitat Needs Of Drift-Feeding Salmonids, R. Craig Addley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A mechanistic model is developed to determine the habitat needs of drift-feeding stream salmonids from the direct cause-and-effect relationships of environmental and physiological variables on net energy intake (NEI). The model determines NEI by subtracting energy costs (basal metabolism, swimming cost, digestion cost) and losses (egestion and excretion) from the gross energy intake obtained as a result of simulated prey capture. The prey capture portion of the model utilizes components of the predation model of C.S. Holling and the prey capture model of N.F. Hughes and L.M. Dill to determine the rate of prey capture (gross energy intake) as a …


Probable Maximum Flood Estimation In Northern Utah, Khin Maung Win May 1993

Probable Maximum Flood Estimation In Northern Utah, Khin Maung Win

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The probable maximum flood (PMF) is used for the xxi assessment of maximum flood potentials in spillway sizing of new dams and in evaluating the adequacy of existing hydrologic structures. Determination of the PMF begins with the estimation of the probable maximum precipitation (PMP) for a particular dam site. Selecting hydrologic methods and assumptions for converting PMP to PMF, which are most appropriate for Utah conditions, is important to meet current inflow design flood (IDF) safety standards.

The objectives of this study were (a) to demonstrate a maximization approach to PMF determination, (b) to evaluate effects of basin characteristics and …


Practical Optimization Modeling For Contaminant Plume Management, Richard C. Peralta, Alaa H. Aly May 1993

Practical Optimization Modeling For Contaminant Plume Management, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

Simulation/optimization (S/0) models can be used to greatly speed the process of computing desirable groundwater pumping strategies for plume management. They make the process of computing optimal strategies fairly straightforward and can help minimize the labor and cost of groundwater contaminant clean-up.


A Complexity Analysis Of Smart Pixel Switching Nodes For Photonic Extended Generalized Shuffle Switching Networks, Thomas J. Cloonan, Gaylord W. Richards, Anthony L. Lentine, Frederick B. Mccormick, Harvard Scott Hinton, Stephen J. Hinterlong Jan 1993

A Complexity Analysis Of Smart Pixel Switching Nodes For Photonic Extended Generalized Shuffle Switching Networks, Thomas J. Cloonan, Gaylord W. Richards, Anthony L. Lentine, Frederick B. Mccormick, Harvard Scott Hinton, Stephen J. Hinterlong

Electrical and Computer Engineering Faculty Publications

This paper studies the architectural tradeoffs found in the use of smart pixels for nodes within photonic switching interconnection networks are discussed. The particular networks of interest within the analysis are strictly nonblocking extended generalized shuffle (EGS) networks. Several performance metrics are defined for the analysis, and the effect of node size on these metrics is studied. Optimum node sizes are defined for each of the performance metrics and system-level limitations are identified.


Multiple Quantum-Well Technology Takes Seed, Harvard S. Hinton Jan 1993

Multiple Quantum-Well Technology Takes Seed, Harvard S. Hinton

Electrical and Computer Engineering Faculty Publications

Progress in the development of self-electrooptic-effect devices (SEEDs) is discussed. The devices include the resistor-SEED (R-SEED) device, which can be viewed as a simple NOR gate. The symmetric SEED (S-SEED) and the logic-SEED (L-SEED) devices with improved features, functionality, and performance are also considered. The integration of FETs with multiple quantum well (MQW) modulators (FET-SEED), enables optical interconnections of electronic circuits. Where the SEED technology can be used is discussed, and an experimental optical switching fabric made using these devices is described.


The Effect Of Peo Ratio On Degradation, Calcification And Bone Bonding Of Peo/Pbt Copolymer (Polyactive), C. A. Van Blitterswijk, J. V.D. Brink, H. Leenders, D. Baaker Jan 1993

The Effect Of Peo Ratio On Degradation, Calcification And Bone Bonding Of Peo/Pbt Copolymer (Polyactive), C. A. Van Blitterswijk, J. V.D. Brink, H. Leenders, D. Baaker

Cells and Materials

In this study, we evaluated the effect of PEO/ PBT proportion on the behavior of a range of PEO/ PBT segmented copolymers (Polyactive) during subcutaneous and intrabony implantation in the rat. It was demonstrated that varying the PEO proportion affected degradation, calcification and bone-bonding. The PEO/PBT 70/30 and 60/40 showed extensive degradation after 1 year, PEO/PBT 55145 an intermediate degradation, and the 40/60 and 30170 copolymers showed little and hardly any degradation respectively. PEO content also affected the degree of calcification . PEO/PBT 70/30 showed extensive and early calcification whereas almost no calcification was seen with PEO/PBT 30170. Since calcified …


Mineralized Matrix Synthesis By Isolated Mouse Odontoblast-Like Cells In Vitro, P. B. Andrews, A. R. Ten Cate, J. E. Davies Jan 1993

Mineralized Matrix Synthesis By Isolated Mouse Odontoblast-Like Cells In Vitro, P. B. Andrews, A. R. Ten Cate, J. E. Davies

Cells and Materials

First mandibular molar tooth germs were dissected from 17 day mouse embryos. The dental papilla was isolated using both mechanical separation and enzymatic digestion. The cells of the papilla were then enzymatically disaggregated and cultured in 35 mm polystyrene dishes containing alpha minimum essential medium supplemented with 15 % fetal calf serum, 50 μglml ascorbic acid, 1 o-8 M dexamethasone and 10 mM Na-13-glycerophosphate. The cultures were maintained for 23 days. The cultured cells initially appeared as large flat cells having numerous cell processes. Multilayered cell nodules, distributed randomly in the cultures, were apparent after 5 days. Matrix was visible …


Microstructural Enhancement Of Dental Composite And Ceramic Materials By Plasma Etching, H. J. Mueller, M. S. Bapna Jan 1993

Microstructural Enhancement Of Dental Composite And Ceramic Materials By Plasma Etching, H. J. Mueller, M. S. Bapna

Cells and Materials

Radio frequency plasma etching of a selected number of dental materials , including glass filled polymeric composites, alumina reinforced ceramic, glass ionomer, and zinc oxide eugenol enhanced microstructural detail for scanning electron microscopy analyses. All four plasmas, argon , oxygen, carbon tetrafluoride (CF4), and CF4 + 4% 0 2 , proved effective, but the latter was the most effective. The etching of all materials , except the ceramic, was accomplished by the selective removal of a polymeric component. For the glass filled composites , this involved removal of the Bis-GMA matrix resin, leaving the filler particles in relief. For a …


Analysis Of The Bony Interface With Various Types Of Hydroxyapatite In Vitro, J. D. De Bruijn, J. S. Flach, K. De Groot, C. A. Van Blitterswijk, J. E. Davies Jan 1993

Analysis Of The Bony Interface With Various Types Of Hydroxyapatite In Vitro, J. D. De Bruijn, J. S. Flach, K. De Groot, C. A. Van Blitterswijk, J. E. Davies

Cells and Materials

Rat bone marrow cells, capable of forming bonelike tissue, were cultured on three types of plasma sprayed hydroxyapatite that differed in degree of crystallinity from 15%, 43% to 69%. The interface between the mineralized extracellular matrix and the hydroxyapatite was studied with scanning and transmission electron microscopy. At the onset of bone formation, calcium and phosphorous-rich afibrillar globules, with a diameter varying from 0.2 to 0.8 μm, were produced and deposited onto the different substrata. These globules subsequently fused to form a homogeneous layer to which collagen fibres became anchored. Individual globules could be distinguished on the non-degrading 69 % …


Scanning Electron Microscopy Of The Osteoclast-Bone Interface In Vivo, H. Zhou, R. Chernecky, J. E. Davies Jan 1993

Scanning Electron Microscopy Of The Osteoclast-Bone Interface In Vivo, H. Zhou, R. Chernecky, J. E. Davies

Cells and Materials

Rat femoral bones were studied by scanning electron microscopy to demonstrate the morphology of osteoclast- bone matrix interfacial relationships. Two general morphological types of actively resorbing osteoclasts were observed . One cell type was approximately ovoid with highly fimbriated borders, fully attached and closely adapted to the resorption surface. The ruffled border of such cells was composed of a number of individual filopodia which were of uniform , regular shape and approximately 2-3 μm in length and 150 nm in diameter. They were found to penetrate the bone matrix to a depth of 1 μm and interdigitated with the surrounding …


The Effect Of Substratum Roughness On Osteoclast-Like Cells In Vitro, K. Gomi, J. D. De Bruijn, M. Ogura, J. E. Davies Jan 1993

The Effect Of Substratum Roughness On Osteoclast-Like Cells In Vitro, K. Gomi, J. D. De Bruijn, M. Ogura, J. E. Davies

Cells and Materials

Calcium phosphate powders were used to produce three groups of experimental substrata for the culture of primary rat bone marrow cells in conditions which permitted the survival and function of osteoclasts. Each of the three experimental groups were subdivided by differences in substratum surface roughness and following a culture period of 7 to 11 days, the culture units were stained for tartrate-resistant acid phosphatase activity. In all samples both small, sometimes mononuclear, and large multinucleate cells stained positive for tartrate-resistant acid phosphatase activity and the numbers and types of cells were quantified and statistically analyzed. Following histochemical staining the samples …


A Simple Freeze Fracture Technique For Scanning Electron Microscopy Of Collagenous Biomaterials, David L. Christiansen, George Pins, Frederick H. Silver Jan 1993

A Simple Freeze Fracture Technique For Scanning Electron Microscopy Of Collagenous Biomaterials, David L. Christiansen, George Pins, Frederick H. Silver

Cells and Materials

A simple freeze fracture technique for the ultrastructural analysis of fragile collagenous biomaterials is presented. Following standard methods of preparation and dehydration, fragile biomaterials are fractured with a sharp blade attached to a modified slide hammer. The sliding mass imparts a sudden impact load on the frozen surface of the material , creating a distortion free cleavage plane across the material. More traditional methods including bending and cutting with scissors introduce artifacts indirectly associated with stress concentration produced by bending, and sample compression at the edges with cutting. The impact loading of the sample during fracture results in preservation of …


Ultrastructural, Cytochemical, And Immunocytochemical Studies On Bone And Its Interfaces, M. D. Mckee, A. Nanci Jan 1993

Ultrastructural, Cytochemical, And Immunocytochemical Studies On Bone And Its Interfaces, M. D. Mckee, A. Nanci

Cells and Materials

Bone cells possess the ability to synthesize, secrete and direct the assembly and maintenance of extracellular matrix to form a functionally rigid and/or weight-bearing mineralized tissue complex, the skeleton. The skeleton not only supports and protects the organs and tissues of the body, but also acts as a mineral ion reservoir for maintaining systemic calcium balance (calcium homeostasis). The remarkable biological precision necessary for the formation, turnover and constant adaptation of bone to external mechanical forces is a dynamic process requiring a coordinated cellular effort relying on a variety of cell-cell and cell-matrix/mineral interactions. Indeed, cell-matrix interfaces found in a …


The Peo/Pbt Copolymer-Mineralized Matrix Interface In Vitro, A. M. Radder, J. E. Davies, H. Leenders, C. A. Van Blitterswijk Jan 1993

The Peo/Pbt Copolymer-Mineralized Matrix Interface In Vitro, A. M. Radder, J. E. Davies, H. Leenders, C. A. Van Blitterswijk

Cells and Materials

Previous implantation experiments have investigated the interaction between a series of PEO/PBT copolymers (Polyactive®) and bone tissue, and shown the morphology of bone-bonding with several PEO/PBT ratios. However, the underlying mechanism of bone-bonding remains largely unknown. Therefore, an in-vitro approach was chosen to obtain more information on the events occurring at the PEO/PBT copolymer-bone interface. Rat marrow cells were cultured on two PEO/PBT copolymer proportions: a 60/40 ratio which is known to bond with bone tissue in-vivo and a 30170 ratio which, within one year of implantation, does not bond with bone. Evaluation was performed with light microscopy, scanning, backscatter …


Heating Of Calcium Phosphate Crystals: Morphological Consequences And Biological Implications, W. Bohne, J. A. Pouezat, L. Peru, G. Daculsi Jan 1993

Heating Of Calcium Phosphate Crystals: Morphological Consequences And Biological Implications, W. Bohne, J. A. Pouezat, L. Peru, G. Daculsi

Cells and Materials

Sintering hydroxyapatite (HA) and ß-tricalcium phosphate (ß-TCP) affects the chemical composition, the crystallinity, and the morphological features as demonstrated by means of X-ray diffraction (XRD) , infrared spectroscopy (IR), and scanning electron microscopy (SEM). When heated to 1230°C, 16.7% of HA had decomposed to ß-TCP. SEM investigations showed homogeneous, sharp angular polyhedric blocks of 30 to 50 µm with rare surface pores. On heating at 1230°C, ß-TCP had entirely transformed to a-TCP. During sintering, the size of the powder grains increased and progressive bridging between the grains was observed. At 1230°C, a network within round-shaped polyhedric blocks of 50 to …


Multinucleated Giant Cells-Hydroxyapatite Interactions: A Time-Related Quantitative Study In A Rat Skull Defect, J. M. Dersot, A. Llorens, J. L. Saffar Jan 1993

Multinucleated Giant Cells-Hydroxyapatite Interactions: A Time-Related Quantitative Study In A Rat Skull Defect, J. M. Dersot, A. Llorens, J. L. Saffar

Cells and Materials

The implantation of calcium phosphate ceramics in the bone environment elicits the differentiation of multinucleated giant cells (MNGCs). MNGC interactions with both crushed and standard hydroxyapatite (HA, Bioapatite ®) particles (cHA and sHA) were studied in rat skull defects. Light microscopy (LM) of undemineralized material after 21 and 42 days of implantation showed that the number of particles in the defect significantly decreased (about SO%) with the two HA forms. Concomitantly, average cHA particle size increased significantly due to the elimination of the smallest particles by the MNGCs. The number of MNGCs per mm2 of defect decreased significantly between 21 …


Surface Subsidence Over A Room-And-Pillar Mine In The Western United States, United States Department Of The Interior, Bureau Of Mines Jan 1993

Surface Subsidence Over A Room-And-Pillar Mine In The Western United States, United States Department Of The Interior, Bureau Of Mines

Mines and Mineral Resources

This report summarizes the results from the subsidence research study completed by the U.S. Bureau of Mines at the Roadside Mine, Powderhorn Coal Co., Palisade, CO. This research was conducted from February 1981 to August 1985, with additional data obtained during July 1991, to evaluate residual subsidence. The Bureau studied subsidence at three distinct room-and-pillar sections at separate locations over the mine and determined the maximum subsidence values and surface subsidence profiles for each mining section. Maximum subsidence of 3.0 ft. occurred over the room-and-pillar sections, with over-burden depths ranging from 50 to 600 ft. Surface tension cracks had occurred, …


Osteoclastic Resorption Of Calcium Phosphate Ceramic Thin Films, J. E. Davies, G. Shapiro, B. F. Lowenberg Jan 1993

Osteoclastic Resorption Of Calcium Phosphate Ceramic Thin Films, J. E. Davies, G. Shapiro, B. F. Lowenberg

Cells and Materials

Sub-micron calcium phosphate ceramic thin films were formed by vertically dipping transparent quartz plates in a particulate sol-gel suspension. Primary adult rat bone marrow cell populations were cultured on the ceramic thin films in conditions known to allow the differentiation of cells of the osteoclast lineage. Monitoring the cultures for periods of 11 to 28 days revealed the creation of resorption lacunae in the thin films by multinucleate cells. Some cultures were heated at 42 °C overnight to remove adherent cells; using bright field light microscopy (LM), after staining with silver nitrate, the degree of resorption could be easily assessed. …


Computer Methodology For Transportation Agencies To Screen Technologies For Hazardous Waste Remediation, William J. Grenney, Ravi Kumar Penmetsa Jan 1993

Computer Methodology For Transportation Agencies To Screen Technologies For Hazardous Waste Remediation, William J. Grenney, Ravi Kumar Penmetsa

Reports

Executive Summary: Many pathways exist for transportation agencies and other public and private agencies to become responsible for sites contaminated by hazardous wastes. As a reult, agencies frequently face a multitude of lega, regulatory, financial, technical, and health risk problems. When transportation agencies become involved in the remediation of hazardous waste sites, the common practice is to hire consultants and contractors for the clean up process. Because the field of hazardous waste site remediation is changing so rapidly, agency personnel evaluating the consultant's recommendations need to ahve access to the most recent regulatory and remediation information. Early stages of the …


In Vitro Studies Of Encrustations On Catheters, A Model Of Infection Stone Formation, W. Schmitz, A. Nolde, G. Marklein, A. Hesse Jan 1993

In Vitro Studies Of Encrustations On Catheters, A Model Of Infection Stone Formation, W. Schmitz, A. Nolde, G. Marklein, A. Hesse

Cells and Materials

Deposition of infection-induced stone material on urinary catheters is a common problem in urological patients. Therefore, a crystallization model was developed in order to form this material in a reproducible manner. Furthermore, the dissolving potency of two solutions (Suby-G® and Solution-R®) was investigated with this model. The encrustations were examined by infrared (IR) spectroscopy, chemical encrustation analysis , scanning electron microscopy (SEM) and X-ray microanalysis. In addition, the encrustations were calculated from the results of the urine analysis, before and after each experiment, as contents remaining in each artificial bladder. The model conditions changed during the experiment and led to …