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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.

Gro-Sat: The Development Of An Extended Life Support System For Plants In Microgravity, Kathleen Blizard, Robert Jacobs, Kathryn Chevalier, Brenda Paul

Small Satellite Conference

The effects of a microgravity environment on the entire life cycle of plants is not yet fully understood. A conceptual design for the payload of a Get Away Special canister has been developed to implement a complete life support system for plants. This small satellite is a closed system that must maintain plant life for at least three months. It consists of an innovative lighting system and a complete plant nutrient delivery system. The use of hardware to limit long-term contamination of the nutrient solution in the closed system as well as other considerations are discussed. The design, based on …

Observations On The Enamel Of Odontomas, Carla Marchetti, Cesare Piacentini, Paolo Menghini, Marcella Reguzzoni

Scanning Microscopy

The morphological study of odontomas provides an alternative model for observing the formation of dental tissues, since different maturing stages are present simultaneously. Investigations were performed on decalcified samples (using light microscopy and transmission electron microscopy) and on undecalcified samples of complex odontoma enamel (using transmission electron microscopy). Simultaneous presence of prismatic enamel at various maturing stages with different structural characteristics was observed. Such enamel was sometimes associated with layers of ameloblastic cells with characteristics of cells in functional activity. In other sites, the enamel did not present a prismatic structure but it appeared as unstructured material clusters with abundant …

Ascorbic Acid Is An Abettor In Calcium Urolithiasis: An Experimental Study, P. P. Singh, R. Kiran, A. K. Pendse, Reeta Ghosh, S. S. Surana

Scanning Microscopy

Two sets of animal experiments using guinea pigs were planned to evaluate the effect of ascorbic acid supplementation on the lithogenic process. In the first set of experiments, 10, 40, and 60 mg doses of ascorbic acid/100g body weight/day were given for 105 days. Neither of the ascorbic acid doses given induced crystalluria, calcification or stone formation, thereby confirming our previous findings that ascorbic acid in the doses used by clinicians does not cause urolith formation. In the second set of experiments, ascorbic acid was supplemented in hypercalciuric (induced by calcium carbonate feeding) and hyperoxaluric (induced by sodium oxalate feeding) …

A Simulation Model For Electron Irradiation Induced Specimen Charging In A Scanning Electron Microscope, D. S. H. Chan, K. S. Sim, J. C. H. Phang

Scanning Microscopy

A numerical model has been formulated to simulate the dynamics of specimen charging in a scanning electron microscope. In this model, the electric field due to imposed boundary conditions and fixed charges is solved by the finite element method. The empirical electron yield data are stored in "Universal Yield Curves (UYC)". These UYCs control the generation of secondary and backscattered electrons from various materials. The electrons emitted from electron-solid interactions are tracked using a leapfrog integration scheme. Excess charges generated on the surface of electrically floating solids are assigned to numerical grids using a linear charge redistribution scheme. The validity …

Convective Turing Patterns, D. A. Vasquez, J. W. Wilder, Boyd F. Edwards

All Physics Faculty Publications

Turing patterns involve regions of different chemical compositions which lead to density gradients that, in liquids, are potentially unstable hydrodynamically. Nonlinear hydrodynamics coupled with a model of Turing pattern formation show that convection modifies and coexists with some Turing patterns and excludes others, and thereby plays a significant role in pattern selection.

Scanning Electron Microscopy Of Human Esophageal Mucosa In Patients With Carcinoma Of The Esophagus, M. Cwikiel, M. Q. Yang, M. Albertsson, C. -H. Håkansson, M. Palmegren

Scanning Microscopy

Specimens taken at surgery from 15 patients with carcinoma of the esophagus were examined with scanning electron microscopy. Nine patients were treated with chemotherapy (cisplatin + 5-fluorouracil), surgery and radiotherapy; one received preoperative radiotherapy only; and the remaining five primary surgery only. Scanning electron microscopy was performed on specimens of both tumor tissue and the mucosa at least 5 cm from the tumor. In adjacent non-tumor tissue, damage due to treatment was observed in the form of changes in microridges and increased cell loss. In tumor tissue, the degree of damage was correlated to tumor response to treatment. For patients …

A Combined Near Field Optical And Force Microscope, M. H. P. Moers, R. G. Tack, N. F. Van Hulst, B. Bölger

Scanning Microscopy

Scanning near field optical microscopy (SNOM) is the optical alternative of the scanning probe microscopical techniques which enables a lateral resolution down to about 10 nm, unlimited by diffraction. Moreover, the potential of non-destructive imaging of chemical and biological samples with nanometer resolution in ambient conditions is a crucial advantage over electron microscopy.

An integrated microscope has been constructed which allows simultaneous detection of optical and force interaction between a microfabricated SiN probe and a sample surface. Images are obtained in a transmission mode by detection of the light emanating from a "supertip" in contact with the sample surface and …

Nuclear Microprobe For Integrated Circuit Process Inspection, Mikio Takai, Ryoh Mimura, Hiroshi Sawaragi, Ryuso Aihara

Scanning Microscopy

A nuclear microprobe with a minimum beam-spot diameter of less than 100 nm, intended for application to IC (integrated circuit) process inspection, has been designed and installed at Osaka University. An ultra high-vacuum sample-chamber with a three-axis goniometer stage and a toroidal electrostatic analyzer for medium energy ion scattering (MEIS) was combined with a short acceleration column for a focused ion beam. A liquid metal ion source (LMIS) for light metal ions such as Li⁺ or Be⁺ was mounted on the short column. A minimum beam spot-size of about 80 nm with a current of 30 pA was …

Characterization Of The Complex Sulfide Ore Of Sotiel (Spain) By Scanning Electron Microscopy And Electron Microprobe Analysis, Giuseppe Bonifazi, Roberto Gorga

Scanning Microscopy

This study complements a more exhaustive examination on the complex sulfide mineralization of Sotiel, (Spain), by optical microscopy and multispectral digital analysis of images. Electron microscopy analyses were carried out to document specific associations which are difficult to detect with conventional optical microscopy. This study utilizes the application of digital techniques to image processing, in an attempt to define microstructural and microtextural characteristics of the ore, since they play an important role in the subsequent beneficiation operations (i.e., flotation).

Scientific and economic information bound to complex metallogenic phenomenology and referred to particular paragenetic scenes was acquired by the study in …

Nanometer-Scale Synthesis And Atomic-Scale Modification With The Scanning Tunneling Microscope, Reginald M. Penner

Scanning Microscopy

The structure or composition of a surface may be locally altered in either of two fundamental ways using the scanning tunneling microscope (STM). A modification of the surface may be induced resulting in the rearrangement and/or removal of surface atoms, or in the transfer of atoms from the tip to the sample surface. In many recent experiments, the modification of surfaces has involved a single atom or an ensemble of a few atoms. Alternatively, the localized synthesis of a new material from reactants external to the STM tip and sample can be induced using at least three experimental strategies. A …

Scanning Electron Microscopic Examination Of Intracanal Wall Dentin: Hand Versus Laser Treatment, H. E. Goodis, J. M. White, S. J. Marshall, G. W. Marshall Jr.

Scanning Microscopy

Conventional cleaning and shaping of root canal spaces involves the use of hand and rotary instruments with irrigation. The procedure results in the formation of a smear layer consisting of dentin shavings, organic tissue remnants and microorganisms. The laser has been suggested as an aid in root canal preparation. In this study, pulsed and continuous wave 1.06 μm wavelength Nd:YAG lasers were used to compare their abilities to clean and shape root canal spaces to conventional methods. After preparation, the test teeth were sectioned longitudinally and examined by scanning electron microscopy. The results demonstrated that the laser was capable of …

The Present Status Of Cathodoluminescence Attachments For Optical Microscopes, Donald J. Marshall

Scanning Microscopy

The serious use of cathodoluminescence (CL) in petrography began about 30 years ago with the electron microprobe analyzer. Investigators soon began to use simpler instruments mounted directly on optical microscopes - cathodoluminescence microscope attachments (CMAs).

A major advantage of the CMA, compared to a scanning electron microscope (SEM) or electron microprobe analyzer (EMPA), is the capability to switch quickly between CL observations and high quality conventional optical microscope observations. Beam currents available in the CMA are higher than in the SEM or EMPA and one sees an instantaneous real time true color display of the CL pattern.

CMAs are based …

Morphological Characterization Of The Radiation Sensitive Cell Line, Xrs-5, Carol C. Korte, Linda S. Yasui

Scanning Microscopy

Morphometric analysis was performed on the radiation sensitive Chinese hamster ovary (CHO) xrs-5 cell line, reverting xrs-5 cells and parental K1 cells. Several ultrastructural parameters (increased nuclear envelope membrane separation, cell and nuclear volume, nuclear to cytoplasmic ratio, and the nuclear surface area per unit volume of the cell) were measured and correlated with radiation sensitivity. A trend in increased cell size and radiosensitivity was observed. However, only the substantially increased nuclear envelope membrane separation in sensitive xrs-5 cells significantly correlated with radiation sensitivity. The maximal nuclear envelope membrane separation in sensitive xrs-5 cells was 270.8 nm. The maximal K1 …

New Methods For Depositing And Imaging Molecules In Scanning Tunneling Microscopy, Victor N. Morozov, Nadrian C. Seeman, Neville R. Kallenbach

Scanning Microscopy

Methods and apparatus are described to deposit and image molecules by scanning tunneling microscopy (STM) under an inert atmosphere. Three methods of applying molecules have been evaluated: equilibrium adsorption from the vapor phase, sublimation, and electrospraying. Using these methods, a variety of organic and biopolymer molecules have been deposited and imaged on graphite and on gold (111), grown epitaxially on mica. Compared with alternatives, such as the use of high vacuum apparatus or glove boxes, these procedures offer some important advantages: they are inexpensive, convenient, and more rapid. Mercaptoethanol, ethanolamine, ethanol, acetic acid, and water produce two-dimensional crystalline adlayers on …

The Interaction Between Nephrocalcin And Tamm-Horsfall Proteins With Calcium Oxalate Dihydrate, Sergio Deganello

Scanning Microscopy

Studies of crystals of calcium oxalate dihydrate (COD) grown by vapor diffusion from solutions contain-ing 5.1 x 10^-7, 1.5 x 10^-6, and 1.0 x 10^-5 M nephrocalcin (NC), indicate that NC profoundly affects COD's habit, size and structure. The decrease in COD size is such that at 1.0 x 10^-5 M NC, the dimensions of the crystals are reduced about five-fold with respect to those of a NC-free control. In addition, the planes of the {101} form disappear, the original habit is lost, and the diffraction pattern deteriorates to such an extent that only …

Three-Dimensional Cytoskeletal Structures Of The Chinchilla Organ Of Corti: Scanning Electron Microscopy Application Of The Polyethylene Glycol Method, A. Nagasawa, R. V. Harrison, R. J. Mount, Y. Harada

Scanning Microscopy

We describe the application of a polyethylene glycol (PEG) embedding technique to examine the sensory and supporting structures of the inner ear. The chinchilla organ of Corti was exposed by cracking PEG embedded cochleas. A range of PEG molecular weights (2000-8000) were utilized; PEG 2000, with a melting point of 57°C was preferred. After removal of the PEG, the three-dimensional aspects of intracellular structures were observed using scanning electron microscopy. Filamentous elements in the hair cell cuticular plate and in the supporting cells were clearly observed, as was the mesh work of cross-linked actin filaments in the cuticular portion of …

High Resolution Electron Microscopy Of The Junction Between Enamel And Dental Calculus, Yoshihiko Hayashi

Scanning Microscopy

Newly formed dental calculus grows on the enamel surface after the tooth crown is exposed to the oral environment. In order to demonstrate the crystal coherence, the junction between enamel and dental calculus was examined in the high resolution electron microscope. Ultrathin sections were also used for selected area electron diffraction to reveal any newly formed mineral phase.

High resolution electron microscopy (HREM) revealed that lattice fringes of dental calculus crystals directly coincided with those of enamel crystals. Two types of coherence were identified at the junction: in one type, a dental calculus crystal contacted the side of an enamel …

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

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 …

Utah Science Vol. 54 No. 2, Summer 1993

Utah Science

38 The Utah Climate Center

48 Program Provides Information About Benefits of Pesticide Use

49 Research in Brief

24 Gender and Housework: Traditional Roles Persist

60 Families Still Share Some Meals

62 The Role of the Land Grant University in Management of Public Lands-Land Grant Days 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, …

Scanning Tunneling Microscopy: A Chemical Perspective, C. Julian Chen

Scanning Microscopy

In this review article, scanning tunneling microscopy (STM) is presented in a chemical perspective. The typical distance from the nucleus of the apex atom of the tip to the top-layer nuclei of the sample is 4-6 Å, where a strong attractive atomic force, i.e., a partial covalent bond, arises between the tip and the sample. The origin of the covalent bond is the back-and-forth transfer of electrons between two atoms, which Pauling has called resonance. While a bias voltage is applied between them, a net electron current in a specific direction arises. This tunneling current is a result of …

Immunological Pathogenesis Of Endolymphatic Hydrops And Its Relation To Meniere's Disease, S. Tomiyama, T. Yagi, M. Sakagami, K. Fukazawa

Scanning Microscopy

This study was designed to investigate an immunologically induced endolymphatic hydrops (ELH) and to focus on the issue of its pathogenesis in relation to Meniere's disease. The time course of ELH was evaluated by light microscopy in a 2-hour to 7-month period following direct antigen challenge to the endolymphatic sac (ELS) in systemically pre-sensitized guinea pigs. ELH began to appear in the vestibule and the basal turn 5-7 hours after inner ear challenge and developed gradually. During the interval from the second day to the first week, ELH rapidly developed in all the cochlear turns and reached a maximum size. …

An Energy Dependent Model For Type I Magnetic Contrast In The Scanning Electron Microscope, W. K. Chim, D. S. H. Chan, J. C. H. Phang, T. S. Low, S. Thirumalai

Scanning Microscopy

The modelling of the magnetic contrast phenomenon in the scanning electron microscope (SEM) is important in understanding the physics of the contrast mechanism and the associated signal detection. In this paper, we report an improved analytical model for Type I magnetic contrast calculations using an approximate form of the Chung and Everhart secondary electron (SE) energy distribution. Previous studies have neglected this factor by assuming a mono-energetic model in order to simplify the calculations. This new model can be used to study different material specimens by appropriate choice of the work function and field-distance integral. The effect of energy filtering …

Evaluation Of Erbium:Yag Laser Radiation Of Hard Dental Tissues: Analysis Of Temperature Changes, Depth Of Cuts And Structural Effects, A. F. Paghdiwala, T. K. Vaidyanathan, M. F. Paghdiwala

Scanning Microscopy

Temperature elevations, depths of cuts and structural changes produced by 2.94 micron pulsed Erbium:YAG laser radiation of hard dental tissues, at different power levels and exposure times of the laser, were studied. The depth of cut produced was found to vary significantly as a function of power level and exposure time on dry teeth. The mean temperature rise with laser radiation was also influenced both by power level and time of exposure. The effect of water flow on the teeth during laser exposure was evaluated; the results indicate that the ablation efficiency was better, temperature elevations lower and structural changes …

Scanning Electron Microscopy Of Age-Related Changes In The C57bl/6j Mouse Cochlea, Kunihiro Mizuta, Osamu Nozawa, Hirofumi Morita, Tomoyuki Hoshino

Scanning Microscopy

Hair cells and nerve fibers inside the organ of Corti of the C57BL/6J mouse, which is known as the precocious presbycusis model, were studied using the scanning electron microscope. For this study, we used thick serial sections cut from celloidin blocks.

In the 5-week-old mice, hair cell loss was not seen. The upper tunnel radial fibers crossed the upper part of the tunnel of Corti and entered the Nuel's space between the outer pillar cells. The fibers varied in diameter and showed many varicosities. The basilar fibers emerged into the tunnel of Corti beneath the upper tunnel radial fibers …

Sample Preparation Techniques For Conventional And High Resolution Scanning Electron Microscopy Of The Central Nervous System. The Cerebellum As A Model, Orlando J. Castejon

Scanning Microscopy

In the present paper some basic sample preparation techniques for scanning electron microscopy of nervous tissue are described. These basic preparative methods include conventional scanning electron microscopy or slicing technique, ethanol-cryofracturing technique, freeze-fracture method using either liquid nitrogen (slow freezing) or Freon 22 cooled by liquid nitrogen (fast freezing), improved freeze-fracture method with delicate specimen preparation and chromium coating, ultrasonic microdissection, and "creative tearing" technique. Some basic principles, advantages and limitations are critically considered. In addition, some specific applications in neurobiological research are reported. Emphasis is placed upon understanding the sources and nature of artifacts that are likely to be …

A Review Of New Concepts In Renal Stone Research, L. C. Cao, E. R. Boevé, W. C. De Bruijn, W. G. Robertson, F. H. Schröder

Scanning Microscopy

Clinical and basic research in the field of urolithiasis has developed rapidly in recent years. Progress in extracorporeal shock wave lithotripsy (ESWL) and percutaneous nephrolithotomy (PNL) has brought about a revolution in the surgical treatment of urolithiasis and research at the cellular and molecular level is now expanding. In spite of these advances, however, clinical treatment of urolithiasis remains far from satisfactory. Stone recurrence in many patients cannot be predicted and is beyond control of urologists mainly because the mechanisms of stone formation are still not fully understood. It is necessary to study the process of stone formation more intensely …

Analysis Of Synthetic Dnas And Dna-Protamine Complexes With The Scanning Tunneling Microscope, Michael J. Allen, Robert J. Tench, Joe A. Mazrimas, Mehdi Balooch, Wigbert J. Siekhaus, Rod Balhorn

Scanning Microscopy

Three duplex DNAs 22, 47, and 100 base-pairs in length have been imaged with the scanning tunneling microscope (STM) after deposition on highly oriented pyrolytic graphite (HOPG). Images of the 47 base-pair (bp) molecules are resolved sufficiently to identify the two phosphodiester strands, the direction of helical coiling (this molecule contains three turns of left-handed helix), and single-stranded ends. Length measurements indicate that all three DNA sequences have adopted an "A-like" conformation. DNA-protamine complexes were also prepared and imaged under similar conditions. Length measurements of the complexes demonstrate that the binding of bull protamine 1 to the 47-mer stabilizes the …