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Effectiveness Of Carbaryl And Pyrethroid Insecticides For Protection Of Engelmann Spruce From Attack By Spruce Beetle (Coleoptera: Scolytidae), Karen J. Johnson May 1996

Effectiveness Of Carbaryl And Pyrethroid Insecticides For Protection Of Engelmann Spruce From Attack By Spruce Beetle (Coleoptera: Scolytidae), Karen J. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A field experiment tested the effectiveness of carbaryl and two pyrethroid insecticides, cyfluthrin and esfenvalerate, in protecting high-value Engelmann spruce trees from attack by Dendroctonus rufipennis Kirby. Carbaryl suspension at the 2% registered rate and a reduced rate of 1 % were both effective in protecting Engelmann spruce from attack by D. rufipennis through two pheromone baiting periods and 24 months following insecticide application. Cyfluthrin at 0.025% rate and esfenvalerate at 0.025 and 0.05% rates provided effective protection through one pheromone baiting and 12 months following insecticide application. Only cyfluthrin at 0.008% rate was judged ineffective protection 12 months following …


Assessment Of Kokanee Salmon, Oncorhynchus Nerka, Genetic Stocks In Flaming Gorge Reservoir, Utah-Wyoming, Michael F. Canning May 1996

Assessment Of Kokanee Salmon, Oncorhynchus Nerka, Genetic Stocks In Flaming Gorge Reservoir, Utah-Wyoming, Michael F. Canning

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I investigated the relative abundance, spatial distributions, return to the creel, and growth rates of two genetic stocks of kokanee salmon, Oncorhynchus nerka, in Flaming Gorge Reservoir, Utah-Wyoming. The two genetic stocks consist of fish from the two major spawning populations of kokanee in the reservoir. One population, Shore Spawners, spawns along the eastern shoreline of the Open Hills area of the reservoir. The other population, Sheep Creek, spawns in Sheep Creek, a tributary located in the Canyon area of the reservoir.

Mitochondrial DNA of kokanee from each population was analyzed to determine haplotype differences between stocks. These haplotype …


Imaging Molecular Structure Of Channels And Receptors With An Atomic Force Microscope, Ratneshwar Lal Apr 1996

Imaging Molecular Structure Of Channels And Receptors With An Atomic Force Microscope, Ratneshwar Lal

Scanning Microscopy

Biological membranes contain specialized protein macromolecules such as channels, pumps and receptors. Physiologically, membranes and their constituent macromolecules are the interface surfaces toward which most of the regulatory biochemical and other signals are directed. Yet very little is known about these surfaces. The structure of biological membranes has been analyzed primarily using imaging techniques that are limited in their resolution of surface topology. An atomic force microscope (AFM) developed by Binnig, Quate and Gerber, can image molecular structures on specimen surfaces with subnanometer resolution, under diverse environmental conditions. Also, AFM can manipulate surfaces with molecular precision: it can nanodissect, translocate, …


In Vitro Systems And Cultured Cells As Specimens For X-Ray Microanalysis, Godfried M. Roomans, Jarin Hongpaisan, Zhengzhu Jin, Ann-Christin Mörk, Ailing Zhang Apr 1996

In Vitro Systems And Cultured Cells As Specimens For X-Ray Microanalysis, Godfried M. Roomans, Jarin Hongpaisan, Zhengzhu Jin, Ann-Christin Mörk, Ailing Zhang

Scanning Microscopy

In vitro systems and cultured cells are recognized as useful systems in many areas of biomedical research, including X-ray microanalysis. To be reliable, in an vitro system should have an elemental composition close to that of the tissue in situ, react in the same way to stimuli, and retain the in situ regulation of ion transport. In the present paper, four of the most commonly used in vitro systems will be reviewed: incubated tissue slices (liver and pancreas), isolated glands (submandibular gland acini, sweat glands), primary cell cultures (sweat glands, endometrium), and cell lines (the colon cancer cell line …


Accessing Nuclear Structure For Field Emission, In Lens, Scanning Electron Microscopy (Feisem), T. D. Allen, G. R. Bennion, S. A. Rutherford, S. Reipert, A. Ramalho, E. Kiseleva, M. W. Goldberg Apr 1996

Accessing Nuclear Structure For Field Emission, In Lens, Scanning Electron Microscopy (Feisem), T. D. Allen, G. R. Bennion, S. A. Rutherford, S. Reipert, A. Ramalho, E. Kiseleva, M. W. Goldberg

Scanning Microscopy

Scanning electron microscopy (SEM) has had a shorter time course in biology than conventional transmission electron microscopy (TEM) but has nevertheless produced a wealth of images that have significantly complemented our perception of biological structure and function from TEM information. By its nature, SEM is a surface imaging technology, and its impact at the subcellular level has been restricted by the considerably reduced resolution in conventional SEM in comparison to TEM. This restriction has been removed by the recent advent of high-brightness sources used in lensfield emission instruments (FEISEM) which have produced resolution of around 1 nanometre, which is not …


Angiogenesis In The Gonadal Capillary Network Of The Chick Embryo, F. J. Pérez-Aparicio, A. Carretero, M. Navarro, J. Ruberte Apr 1996

Angiogenesis In The Gonadal Capillary Network Of The Chick Embryo, F. J. Pérez-Aparicio, A. Carretero, M. Navarro, J. Ruberte

Scanning Microscopy

Seventy-one chick embryos of both sexes at the 35 Hamburger and Hamilton (H-H) developmental stage were processed for scanning electron microscopy of vascular corrosion casts and of critical point dried specimens, as well as transmission electron- and light microscopy, in order to study the angiogenic structures. The gonadal subepithelial capillary network was located at the level of the tunica albuginea under the covering epithelium. The casts showed a densely-meshed capillary network and numerous sprouting (nodular protrusions or capillary sprouts) and non-sprouting (enlarged vessels and angiogenic holes) angiogenic structures that were randomly distributed and mixed. Four types of angio-genic holes were …


Micrographic Fracture Characterization Of Gallium Arsenide Wafers, H. E. Belsinger Jr., L. D. T. Topoleski, B. Wilner Apr 1996

Micrographic Fracture Characterization Of Gallium Arsenide Wafers, H. E. Belsinger Jr., L. D. T. Topoleski, B. Wilner

Scanning Microscopy

Single crystal gallium arsenide (GaAs) specimens were loaded to failure. Scanning electron microscope examination of fracture surfaces showed that GaAs fails in a brittle manner on {110} planes. Features on these fracture surfaces were used to identify preexisting (critical) flaws that potentially initiated fracture when loaded by tensile stresses. Critical flaws in each specimen were identified by comparison to an intentionally damaged control. The size and shape of critical defects were consistent with existing failure models.


Tc-Mapping And Investigation Of Water-Initiated Modification Of Yba2cu3o7-X Thin Films By Low Temperature Scanning Electron Microscopy, A. V. Bobyl, M. E. Gaevski, S. G. Konnikov, D. V. Shantsev, V. A. Solov'ev, R. A. Suris Apr 1996

Tc-Mapping And Investigation Of Water-Initiated Modification Of Yba2cu3o7-X Thin Films By Low Temperature Scanning Electron Microscopy, A. V. Bobyl, M. E. Gaevski, S. G. Konnikov, D. V. Shantsev, V. A. Solov'ev, R. A. Suris

Scanning Microscopy

The Tc -mapping method using low temperature scanning electron microscopy (LTSEM) has been developed to study the spatial distribution of the critical temperature in high temperature superconducting (HTSC) films with a spatial resolution approaching 2 μm. To achieve so high a spatial resolution, a numerical deconvolution method was applied that eliminated distorting effects associated with the thermal diffusion and with the contribution from the absorbed beam current. The Tc -mapping method was used to investigate modification by water of YBa2Cu3O7-x films grown on (100) MgO and (110) LaAIO3 substrates. The rate of …


Crystallization During Volume Reduction Of Solutions With An Ion-Composition Corresponding To That In The Distal Tubuli, Inge Hojgaard, Anne-Marie Fornander, Mari-Anne Nilsson, Hans Goran Tiselius Apr 1996

Crystallization During Volume Reduction Of Solutions With An Ion-Composition Corresponding To That In The Distal Tubuli, Inge Hojgaard, Anne-Marie Fornander, Mari-Anne Nilsson, Hans Goran Tiselius

Scanning Microscopy

The effect of macromolecules on the crystallization in solutions with an ion-composition and a pH corresponding to that of urine in the distal part of the distal tubuli was examined by recording the number and volume of crystals in a Coulter Multisizer and by studying the crystal morphology with scanning electron microscopy at different degrees of evaporation. The experiments were carried out with 100 ml samples of salt solutions with and without different concentrations of dialysed urine (dU) from normal subjects. Addition of dU resulted in a greater number of crystals and a reduction in the mean crystal volume (MCV). …


A Yohimbine-Dependent, Uk14,304 Induced Ion Transient In Ht29 Cells Studied By X-Ray Microanalysis, Wei Zhang, Godfried M. Roomans Mar 1996

A Yohimbine-Dependent, Uk14,304 Induced Ion Transient In Ht29 Cells Studied By X-Ray Microanalysis, Wei Zhang, Godfried M. Roomans

Scanning Microscopy

The response of HT29 cells to α2-adrenoceptor agonists was investigated by X-ray microanalysis. Treatment of the cells with 10 μM UK14,304, an α2-agonist, resulted in a rise of intracellular Cl and Na, suggesting an antisecretory effect. When the cells were exposed to yohimbine or RX821002, both of which are arantagonists, the former had no effect, whereas the latter produced a minor decrease of the cellular Na, Cl and K concentrations. However, when the cells were pretreated with yohimbine, UK14,304 induced a transient change in ion concentrations, which consisted of a rapid increase of intracellular Cl, Na …


Cytoskeleton Architecture Of C6 Rat Glioma Cell Subclones Whole Mount Electron Microscopy And Immunogold Labeling, Wolfgang Bohn, Dörte Etzrodt, Roland Foisner, Gerhard Wiche, Peter Traub Mar 1996

Cytoskeleton Architecture Of C6 Rat Glioma Cell Subclones Whole Mount Electron Microscopy And Immunogold Labeling, Wolfgang Bohn, Dörte Etzrodt, Roland Foisner, Gerhard Wiche, Peter Traub

Scanning Microscopy

Whole mount electron microscopy of extracted cells combined with immunogold labeling techniques can be used to characterize the cytoskeletal architecture of cultured cells. As shown with subclones of the C6 rat glioma cell line, heavy metal shadowing was suitable for getting basic information concerning the arrangement of the various filament types within the networks. Pure carbon shadowing combined with immunogold double labeling proved to be optimal to identify linkages between filaments, to localize filament associated proteins and to follow the arrangement of filaments in dense arrays such as lamellipodiae and cell margins. Thin connecting filaments which interact with actin as …


Imaging Soft Materials With Scanning Tunneling Microscopy, J. T. Woodward Iv, J. A. Zasadzinski Mar 1996

Imaging Soft Materials With Scanning Tunneling Microscopy, J. T. Woodward Iv, J. A. Zasadzinski

Scanning Microscopy

By modifying freeze-fracture replication, a standard electron microscopy fixation technique, for use with the scanning tunneling microscope (STM), a variety of soft, non-conductive biomaterials can be imaged at high resolution in three dimensions. Metal replicas make near ideal samples for STM in comparison to the original biological materials. Modifications include a 0.1 μm backing layer of silver and mounting the replicas on a fine-mesh silver filters to enhance the rigidity of the metal replica. This is required unless STM imaging is carried out in vacuum; otherwise, a liquid film of contamination physically connects the STM tip with the sample. This …


Experimental Measurements Of Electron Stopping Power At Low Energies, David C. Joy, Suichu Luo, Raynald Gauvin, Pierre Hovington, Neal Evans Mar 1996

Experimental Measurements Of Electron Stopping Power At Low Energies, David C. Joy, Suichu Luo, Raynald Gauvin, Pierre Hovington, Neal Evans

Scanning Microscopy

The electron stopping power has been measured for twelve elements and fifteen compounds, over the energy range from 1 eV to 10 keV, by the analysis of electron energy loss spectra, optical data, and photon mass absorption data. Values of the effective mean ionization potential Jeff and the effective number of participating electrons Neff have also been determined in each case. The results obtained have been compared with other experimental data, with first-principles theoretical calculations, and with a number of proposed analytical models.


2nd Biennial Ultra-High Temperature (Uht) Symposium, Various Authors Mar 1996

2nd Biennial Ultra-High Temperature (Uht) Symposium, Various Authors

Other Documents

No abstract provided.


Energy Dispersive X-Ray Microanalysis Of The Dentin In Rat Molars After Corticosteroid Treatment, Karin Nasstrom, Rolf Odselius, Arne Petersson Mar 1996

Energy Dispersive X-Ray Microanalysis Of The Dentin In Rat Molars After Corticosteroid Treatment, Karin Nasstrom, Rolf Odselius, Arne Petersson

Scanning Microscopy

The aim of this study was to investigate whether the calcium (Ca) and phosphorus (P) composition of corticosteroid induced dentin was the same as in normally developed dentin. Seven rats were given corticosteroids intravenously and three rats served as controls. Energy dispersive X-ray microanalysis (EDX) was carried out on the axially sawn roots of the molars. Measurements were made at 20 sites, equally distributed in the buccal, mesial, lingual and distal direction. The results showed that the Ca/P ratio (weight %) was slightly above 2.0 in both the experimental and the control group, indicating that the corticosteroid induced dentin had …


Patterns Of Calcium Oxalate Crystal Production By Three Species Of Wood Decay Fungi, Jon H. Connolly, Howard J. Arnott, Jody Jellison Mar 1996

Patterns Of Calcium Oxalate Crystal Production By Three Species Of Wood Decay Fungi, Jon H. Connolly, Howard J. Arnott, Jody Jellison

Scanning Microscopy

Wood decay experiments using red spruce wood resting on moist soil were conducted to discern temporal and spatial patterns of calcium oxalate (CaOx) crystal production by three species of fungi over the course of decay. All three species produced crystals of calcium oxalate dihydrate, but not monohydrate, in and on wood. Over the course of decay, the production of CaOx crystals was shown to be heterogeneous in both space and time. The relative quantity, morphology and longevity of CaOx crystals varied among species. Gloeophyllum (G.) trabeum produced substantial quantities of "free" crystals; Fomitopsis (F.) pinicola produced encrusting crystals; and Trichaptum …


Atomic Force Microscopy Of Dna Electrophoresed Onto Silylated Mica, Irène Revenko, Helen G. Hansma Mar 1996

Atomic Force Microscopy Of Dna Electrophoresed Onto Silylated Mica, Irène Revenko, Helen G. Hansma

Scanning Microscopy

A new technique has been developed for electrophoresing DNA molecules from an agarose gel onto a silylated mica substrate where they can be imaged with an atomic force microscope (AFM). With a simple modification, the technique can also be used for polyacrylamide gels. This method does not require purification of samples from the gels. Using tapping mode AFM, we have observed plasmids after electrophoretic separation into two bands. Differences in conformation were observed between the plasmids in the two bands.


Regenerating Synovial Lining Of The Normal Rabbit Knee: A Scanning Electron Microscopy Study, Haim Stein, Daniel Levanon Mar 1996

Regenerating Synovial Lining Of The Normal Rabbit Knee: A Scanning Electron Microscopy Study, Haim Stein, Daniel Levanon

Scanning Microscopy

Regeneration of the synovial lining in the synovectomized rabbit knee was studied using the scanning electron microscope. The resected synovia regenerated considerably 3 weeks after synovectomy. However, 44 weeks following excision, their surface morphology was still very different from that of the normal tissue of intact animals. The regenerated synovia were characterized by three main features: the large number of various patterns, the many fields harboring fibrillation and the almost total lack of a bubble layer (the latter was formerly shown to be predominant on normal, intact synovia). The surface morphology of the non-operated (contralateral) knee differed greatly from that …


Optimal Pumping Strategies To Maximize Dissolved Tce Extraction At Mather Afb, California, Richard C. Peralta, Alaa H. Aly Mar 1996

Optimal Pumping Strategies To Maximize Dissolved Tce Extraction At Mather Afb, California, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

USU first estimated the future TCE concentrations that would result if no pumping strategy were implemented (Figure 5, Scenario AO). Then USU used the procedure of Appendix B with the model formulation of Appendix C to compute optimal pumping strategies. In computing optimal strategies USU cycled until an arbitrary three percent contaminant mass convergence criterion was satisfied.


Determinants Of Weddellite Formation: Chondroitin Sulfates And Citrate Determine Weddellite Formation In Vitro, Kookmin M. Kim Feb 1996

Determinants Of Weddellite Formation: Chondroitin Sulfates And Citrate Determine Weddellite Formation In Vitro, Kookmin M. Kim

Scanning Microscopy

In synthetic urine (SU), addition of oxalate tends to form monohydrates of calcium oxalate. However, addition of oxalate to natural urine preferably forms calcium oxalate dihydrate (COD). Urine apparently contains a determinant for COD formation. To identify the determinant, the effects of pH, temperature, oxalate, calcium, urate, citrate, magnesium, sulfate and chondroitin sulfates (CS) on calcium oxalate crystal formation were studied. Lower temperatures, higher oxalate concentrations and higher pH favored COD formation in a SU. Mixed CS in the presence of citrate were the most decisive determinant of COD formation. Substitution of CS for agar and gelatin produced similar results, …


Potential Sputtering Of Protons With Slow Multiply Charged Ions, Yasunori Yamazaki, Nobukazu Kakutani Feb 1996

Potential Sputtering Of Protons With Slow Multiply Charged Ions, Yasunori Yamazaki, Nobukazu Kakutani

Scanning Microscopy

Experimental findings of insulator sputtering with slow multiply charged ions are reviewed with particular emphasis on proton sputtering, including recent studies which pay attention not only to the yields, but also to the energy distributions of sputtered particles. A simplified scenario of multiply charged ion interaction with a solid surface is discussed, which consists of two stages, i.e., resonant charge transfers well above the surface (the stage I), and a violent collision with the surface transferring a major part of the potential energy (the stage II). A couple of processes relating to the sputtering in the stages I and II …


Effects Of Ionizing Radiation On Cartilage: Emphasis On Effects On The Extracellular Matrix, M. Cornelissen, H. Thierens, L. De Ridder Feb 1996

Effects Of Ionizing Radiation On Cartilage: Emphasis On Effects On The Extracellular Matrix, M. Cornelissen, H. Thierens, L. De Ridder

Scanning Microscopy

In this report, we review data dealing with radiation effects on cartilage. More specifically, we emphasize on alterations caused in the extra-cellular cartilage matrix. Although radiation studies predominantly describe the effect on the structure of DNA and on the mitotic activity of cells, alterations caused by the effect on the non-mitotic activity can also be important. Cartilage, having an extracellular matrix composed of 2 major components, aggrecan and collagen, provides a good model to study this kind of radiation effects. The following topics concerning literature data are summarized: effects on the amount of matrix synthesized, effects on the activity of …


Ionizing Radiation-Induced Apoptosis And Dna Repair In Murine Erythroleukemia Cells, R. Di Pietro, L. Centurione, E. Santavenere, M. A. Centurione, G. Sanitá Di Toppi, L. Zamai, R. Rana Feb 1996

Ionizing Radiation-Induced Apoptosis And Dna Repair In Murine Erythroleukemia Cells, R. Di Pietro, L. Centurione, E. Santavenere, M. A. Centurione, G. Sanitá Di Toppi, L. Zamai, R. Rana

Scanning Microscopy

A morphological study of DNA repair and apoptotic patterns in relationship with cell cycle events was performed on murine erythroleukemia cells. The presence and distribution of DNA replicon sites were evaluated through the BrdU-anti BrdU immunofluorescence and immunogold techniques in light and electron microscopy. Different patterns of labelling and percentages of BrdU positive cells were observed depending on irradiation dose (up to 60 Gy) and time in post-irradiation culture (up to 24 hours). An enlargement of the S phase of the cell cycle was evidenced 18 hours post-irradiation as determined by flow cytometry analysis. The high resolution approach showed that, …


The Nucleation And Growth Of Calcium Phosphate Crystals At Protein And Phosphatidylserine Liposome Surfaces, G. H. Nancollas, A. Tsortos, A. Zieba Feb 1996

The Nucleation And Growth Of Calcium Phosphate Crystals At Protein And Phosphatidylserine Liposome Surfaces, G. H. Nancollas, A. Tsortos, A. Zieba

Scanning Microscopy

The kinetics of calcium phosphate crystal growth at the surfaces of proteins and phospholipids has been investigated using free drift and constant composition methods in supersaturated calcium phosphate solutions (relative supersaturations: with respect to hydroxyapatite, HAP, σHAP = 15.0, and with respect to octacalcium phosphate, OCP, σOCP = 1. 9). Fibrinogen and collagen molecules adsorbed at hydrophobic surfaces as well as uncross-linked collagen fibrils induce ion binding and subsequent nucleation of calcium phosphate. The formation of OCP on phosphatidylserine vesicles introduced to highly supersaturated calcium phosphate solutions probably involves the interaction of the calcium ions with the ionized carboxylic groups …


Hydration-Scanning Tunneling Microscopy As A Reliable Method For Imaging Biological Specimens And Hydrophilic Insulators, M. Heim, R. Eschrich, A. Hillebrand, H. F. Knapp, G. Cevc, R. Guckenberger Feb 1996

Hydration-Scanning Tunneling Microscopy As A Reliable Method For Imaging Biological Specimens And Hydrophilic Insulators, M. Heim, R. Eschrich, A. Hillebrand, H. F. Knapp, G. Cevc, R. Guckenberger

Scanning Microscopy

The recently discovered high lateral conductivity of molecularly thin adsorbed water films enables investigation of biological specimens, and even of surfaces of hydrophilic insulators by scanning tunneling microscopy (STM). Here we demonstrate the capabilities of this method, which we call hydration-STM (HSTM), with images of various specimens taken in humid atmosphere: We obtained images of a glass coverslip, collagen molecules, tobacco mosaic virus, lipid bilayers and cryosectioned bovine achilles tendon on mica. To elucidate the physical mechanism of this conduction phenomenon we recorded current-voltage curves on hydrated mica. This revealed a basically ohmic behavior of the J-V curves without a …


Formation Of Hydrated Calcium Oxalates In The Presence Of Poly-L-Aspartic Acid, Jeffrey A. Wesson, Elaine Worcester Feb 1996

Formation Of Hydrated Calcium Oxalates In The Presence Of Poly-L-Aspartic Acid, Jeffrey A. Wesson, Elaine Worcester

Scanning Microscopy

The effect of poly-L-aspartic acid (PA) on the crystal structure of calcium oxalate crystals grown after spontaneous nucleation was evaluated as a function of relative supersaturation and calcium:oxalate ratio in a buffered salt solution, with pH and ionic strength in the range of normal human urine. PA was used as a model for naturally occurring acidic urine proteins that have been shown to inhibit nucleation and growth of calcium oxalate crystals. The crystals grown were characterized by optical microscopy and X-ray powder diffraction. It was observed that calcium oxalate monohydrate was the preferred crystalline form in the absence of added …


Early Post-Radiation Changes Of Red Blood Cell Shape In Rats, V. D. Zharskaya, A. B. Chukhlovin Feb 1996

Early Post-Radiation Changes Of Red Blood Cell Shape In Rats, V. D. Zharskaya, A. B. Chukhlovin

Scanning Microscopy

Scanning electron microscopy (SEM) of red blood cells in whole blood samples from rats was performed following acute γ-irradiation of animals with 0.25 to 1 Gy. Increased incidence of echinocytosis was observed and found to be dose- and time-dependent. At a higher radiation dose (1 Gy), echinocytosis was revealed within 5 minutes after treatment and persisted up to 3 weeks. The data demonstrate the applicability of SEM for detecting minimal radiation-induced lesions of red blood cells.


Role Of Calcium Oxalate Monohydrate Crystal Interactions With Renal Epithelial Cells In The Pathogenesis Of Nephrolithiasis: A Review, John C. Lieske, Mary S. Hammes, F. Gary Toback Feb 1996

Role Of Calcium Oxalate Monohydrate Crystal Interactions With Renal Epithelial Cells In The Pathogenesis Of Nephrolithiasis: A Review, John C. Lieske, Mary S. Hammes, F. Gary Toback

Scanning Microscopy

Renal tubular fluid in the distal nephron is supersaturated with calcium and oxalate ions that nucleate to form crystals of calcium oxalate monohydrate (COM), the most common crystal in renal stones. How these nascent crystals are retained in the nephron to form calculi in certain individuals is not known. Recent studies from this laboratory have demonstrated that COM crystals can bind within seconds to the apical surface of renal epithelial cells, suggesting one mechanism whereby crystals could be retained in the tubule. Adherence of crystals to cells along the nephron may be opposed by specific urinary anions such as glycosaminoglycans, …


Crystallization And Stone Formation Inside The Nephron, Dirk J. Kok Feb 1996

Crystallization And Stone Formation Inside The Nephron, Dirk J. Kok

Scanning Microscopy

A model is presented visualizing the events leading to calcium-salt, crystal- and stone-formation inside the nephron. For each nephron segment, handling of urine components relevant to stone formation is considered and urine composition determined. This information was applied to nucleation experiments simulating passage of urine through a nephron. The model and in vitro experiments suggest that within normal transit times for the respective nephron segments, particles of a hydroxyapatite-like material first form near the bend in the Loop of Henle of juxtamedullary nephrons. From there on, calcium oxalate particles start to appear: first dihydrate, then monohydrate. In the collecting duct …


Micromorphology Of The Fibers Behind The Frons Plate And Its Adjacent Regions In The Oriental Hornet (Hymenoptera, Vespinae), Jacob S. Ishay, Alina Landsberg, Smadar Pelah Feb 1996

Micromorphology Of The Fibers Behind The Frons Plate And Its Adjacent Regions In The Oriental Hornet (Hymenoptera, Vespinae), Jacob S. Ishay, Alina Landsberg, Smadar Pelah

Scanning Microscopy

The present study describes the fibers occurring in the space extending behind the frons plate, or the region between the ocelli and the clypeal plate of the Oriental hornet. These fibers connect to the brain in the anterior part of the head in a zone which is demarcated by an imaginary line traversing the upper part of the two omrnatidia. Static fibers are present in the upper part and in the center of the space. These static fibers do not move with acceleration of the structures attached to the head. They are perpendicular to the frons plate, are relatively numerous …