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Techniques For The Microanalysis Of Higher Plants With Particular Reference To Silicon In Cryofixed Wheat Tissues, M. J. Hodson, A. G. Sangster Apr 1990

Techniques For The Microanalysis Of Higher Plants With Particular Reference To Silicon In Cryofixed Wheat Tissues, M. J. Hodson, A. G. Sangster

Scanning Microscopy

The applications of x-ray microanalysis in research into silicon in higher plants are reviewed, recent developments are assessed, and new data are presented. Conventionally prepared material [air or freeze drying for scanning electron microscopy (SEM), and glutaraldehyde/osmium tetroxide fixation for transmission electron microscopy (TEM)) has been studied using both wavelength and energy dispersive microanalysis. These techniques are reliable provided that the deposited form of silica is the major focus of investigation. Recently, studies concerning the soluble, mobile forms of silica, and the ionic environment at deposition sites have been initiated. In these investigations x -ray microanalysis has been carried out …


Dermatophyte Morphology: A Scanning Electron Microscopy Study, R. Vazquez, J. M. Riesco, A. Martin Pascual Apr 1990

Dermatophyte Morphology: A Scanning Electron Microscopy Study, R. Vazquez, J. M. Riesco, A. Martin Pascual

Scanning Microscopy

The Dermatophytes are a broad group of fungi belonging to the class Fungii imperfecti that are the causative agents of dermophytosis (ringworm infections). The present work offers an overview of the morphology of these fungi found in cultures according to the scanning electron microscope. The fungi were obtained from cultures left to develop over variable periods of time that would be sufficient for growth. The morphological features of some dermatophytes obtained in artificial cultures are detailed: M. canis, M. gypseum, M. audouini, M. cookei, T. mentagrophytes, T. schoulemu, T. verrucosuin, T. ajelloi, T. prohferans, and E. floccosum. In all …


Studies Of Epithelial Electrolyte Transport By Marker Ions, A. Dörge, R. Rick Mar 1990

Studies Of Epithelial Electrolyte Transport By Marker Ions, A. Dörge, R. Rick

Scanning Microscopy

The paper reviews several recent studies in which marker ions, such as Rb and Br, were used to identify ion transport pathways and membrane properties in epithelia. In the frog skin epithelium, using Rb as a substitute for K, Cl transport mechanisms across the basolateral membranes of principal cells were studied. The data suggest that intracellular Cl is maintained above electrochemical equilibrium by an Na-K-2Cl cotransport system which, under non-stimulated conditions, is normally quiescent.

In toad and frog skins, the route of transepithelial Cl movement was investigated. A subpopulation of mitochondria-rich cells demonstrated a ready exchange of Br with the …


A Comparison Of Three Low Temperature Techniques Of Specimen Preparation For X-Ray Microanalysis, R. J. Condron, A. T. Marshall Mar 1990

A Comparison Of Three Low Temperature Techniques Of Specimen Preparation For X-Ray Microanalysis, R. J. Condron, A. T. Marshall

Scanning Microscopy

A quantitative x-ray microanalytical comparison of intracellular ion concentrations in two tissues (chicken kidney and duck nasal salt gland), prepared as bulk frozen-hydrated, embedded freeze-dried and freeze-substituted samples, shows that there are similar losses of K+ and Pin freeze-dried and freeze-substituted samples in both types of tissue. It is suggested that this may be due to extraction by chloride-free Spurr's resin during infiltration. There was also an indication of an increase in Na+ concentration in freeze-dried samples.

In chicken kidney cells there was a reduction in Mg++ and Ca++ concentrations in freeze-dried and freeze-substituted samples and …


Scanning Electron Microscopy Analysis Of Polyethylene Oxide Hydrogels For Blood Contact, Sylvie Laliberté Verdon, Elliot L. Chaikof, James E. Coleman, Lori L. Hayes, Raymond J. Connolly, Karen Ramberg, Edward W. Merrill, Allan D. Callow Mar 1990

Scanning Electron Microscopy Analysis Of Polyethylene Oxide Hydrogels For Blood Contact, Sylvie Laliberté Verdon, Elliot L. Chaikof, James E. Coleman, Lori L. Hayes, Raymond J. Connolly, Karen Ramberg, Edward W. Merrill, Allan D. Callow

Scanning Microscopy

Hydrogels are a class of synthetic material, composed of a polymer-water matrix and have been proposed as tissue substitutes and drug delivery vehicles. Polyethylene oxide (PEO) hydrogels were synthesized and used to produce coated wires and conduits for baboon blood compatibility studies. Blood-material interactions were studied both by Scanning Electron Microscopy (SEM) and 111In labeled platelet deposition.

SEM processing modifications were first evaluated in order to reduce shrinkage and surface distortion incurred during sample preparation of these high water content materials. Pretreatment with 1% tannic acid reduced bulk shrinkage associated with critical point drying by 10-20%. This effect is …


Survival Of Trout Strains As Affected By Limnological Parameters, Wayne A. Wurtsbaugh, Timothy Modde, Chris Luecke, Cheryl Courtney Mar 1990

Survival Of Trout Strains As Affected By Limnological Parameters, Wayne A. Wurtsbaugh, Timothy Modde, Chris Luecke, Cheryl Courtney

Watershed Sciences Faculty Publications

Juvenile rainbow trout Oncorhynchus mykiss. (ca. 80 mm S.L.) stocked into mid-elevation reservoirs in Utah are vulnerable to predation from piscivorous fish and birds. I determined how effectively juvenile trout used cover to avoid these predators by using direct observations (snorkel transects) on habitat selection in two reservoirs. Observations of juvenile trout were conducted within five weeks of stocking in 1988 and 1989. During the day juvenile trout were abundant in complex inshore habitats. Juvenile trout actively fed during the day but the time of peak feeding was variable. Large Daphnia made of > 95% of the diet of juvenile trout. …


Trophic Interactions Between Fish And Invertebrates In Bear Lake, Utah-Idaho, Wayne A. Wurtsbaugh, Charles P. Hawkins Mar 1990

Trophic Interactions Between Fish And Invertebrates In Bear Lake, Utah-Idaho, Wayne A. Wurtsbaugh, Charles P. Hawkins

Watershed Sciences Faculty Publications

An intensive study of the limnology, invertebrates and fishes of Bear Lake was conducted in 1987 in order to define the productivity and food web of the community. Limno10gica1 parameters and invertebrates were measured at approximately monthly intervals while fish distribution and feeding was analyzed in February, June, August, and October. Samples were collected at three to eight stations along a transect running from the shallow littoral area on the west side of the lake, to the deep profundal zone.


Multielement Analysis Of Biological Materials By Particle-Induced X-Ray Emission (Pixe), Willy Maenhaut Feb 1990

Multielement Analysis Of Biological Materials By Particle-Induced X-Ray Emission (Pixe), Willy Maenhaut

Scanning Microscopy

An analytical particle-induced X-ray emission (PIXE) procedure for the multielement analysis of biological materials consists of various stages. These include sample and specimen preparation, specimen bombardment, spectral data processing, quantification and correction for matrix effects. Critical aspects of the procedure are contamination and/or losses during sample and specimen preparation and the danger of radiation or heat-induced losses during specimen bombardment. With optimized PIXE procedures precisions of 1-2% and an accuracy of better than 5% are obtainable, whereas the detection limits are down to 0.1 μg/g. Because of its inherent characteristics, PIXE offers great potential for trace element analysis in the …


Scanning Electron Microscope Study Of Wohlfahrtia Magnifica (Schiner, 1862) (Diptera: Sarcophagidae) I. Structures With Parasitic And Possible Taxonomic Meaning, I. Ruíz-Martínez, M. D. Soler-Cruz, R. Benítez-Rodríguez, J. M. Pérez-Jiménez, C. Adalid-Fuentes, M. Díaz-López Feb 1990

Scanning Electron Microscope Study Of Wohlfahrtia Magnifica (Schiner, 1862) (Diptera: Sarcophagidae) I. Structures With Parasitic And Possible Taxonomic Meaning, I. Ruíz-Martínez, M. D. Soler-Cruz, R. Benítez-Rodríguez, J. M. Pérez-Jiménez, C. Adalid-Fuentes, M. Díaz-López

Scanning Microscopy

The larval development of Wohlfahrtia magnifica (the most important dipteran causing sheep myiasis in the Palearctic region) has been studied by means of scanning electron microscopy. The ultrastructure of mouth-hooks, oral ridges, labial lobes, body spines and anterior and posterior peritremes is described for the first time. Their possible adaptations to a parasitic lifeway are also discussed. Thus, the use of new structures in the Sarcophagidae taxonomy is proposed from the point of view of their ultrastructure and adaptative morphology.


Responses Of Astrocytes In Culture After Low Dose Laser Irradiation, David T. Yew, D. R. Zheng, C. Au, W. W. Y. Li Feb 1990

Responses Of Astrocytes In Culture After Low Dose Laser Irradiation, David T. Yew, D. R. Zheng, C. Au, W. W. Y. Li

Scanning Microscopy

The effect of Helium-Neon low dose laser on astrocytes was investigated in cultures of isolated astrocytes from albino neonatal rats. The laser appeared to inhibit the growth of astrocytes as exemplified by the smaller sizes of the cells and the decreased leucine uptake in each cell after treatment. Temporary decrease in the number of mitoses was also observed, but this trend was reversed soon after. Electron microscopic studies revealed an increase in buddings from cell bodies and processes (branches) after irradiation.


Growth Stimulants And Feed Additives, Norris J. Stenquist Feb 1990

Growth Stimulants And Feed Additives, Norris J. Stenquist

All Archived Publications

In recent years, the most revolutionary increases in beef cattle weights and feeding efficiencies have resulted from the development and use of growth stimulants, feed additives, and antibiotics. These nonnutritive products not only improve the rate and efficiency of gain but prevent certain diseases as well. Their use has significantly improved beef cattle production efficiency and provided a greater return per dollar invested than any other factor in the livestock industry. Growth stimulants deposit increased protein in the animal without changing protein or energy intake. They are designed to provide a constant slow release of active ingredients into the animal's …


Particle Induced X-Ray Emission Elemental Analysis: Sample Preparation For A Versatile Instrumental Method, N. F. Mangelson, M. W. Hill Jan 1990

Particle Induced X-Ray Emission Elemental Analysis: Sample Preparation For A Versatile Instrumental Method, N. F. Mangelson, M. W. Hill

Scanning Microscopy

Particle induced X-ray emission (PIXE) has found extensive application as a multi-element analysis tool. The energetic nature of both the incident particle beam and the emitted characteristic X-rays has lead to considerable versatility in regard to samples which may be analyzed by the PIXE technique. This paper does not deal with the theory, equipment, or data analysis for PIXE, but it should bring to the reader a broad perspective of methods for sample preparation and should point the way into the literature where more complete details are given. Both physical and chemical processes for sample preparation are outlined. Preparation often …


Evidence That A Major Portion Of Cellular Potassium Is "Bound", Ivan L. Cameron, W. Elaine Hardman, Keithley E. Hunter, Christine Haskin, Nancy K. R. Smith, Gary D. Fullerton Jan 1990

Evidence That A Major Portion Of Cellular Potassium Is "Bound", Ivan L. Cameron, W. Elaine Hardman, Keithley E. Hunter, Christine Haskin, Nancy K. R. Smith, Gary D. Fullerton

Scanning Microscopy

In this report we briefly review recent evidence which shows that a substantial proportion of intracellular K+ is "bound" or perturbed from the physicochemical properties expected in dilute aqueous solutions. In addition, we present evidence from electron probe x-ray microanalysis of thin cryosections of cells which indicates that the binding of K+ to anionic groups either carboxyl groups (HCO2) on proteins or to phosphate groups in creatine phosphate (CrP) , in adenosine triphosphate, (ATP), in protein and in nucleic acids, are the main determinants of the maintenance of (as differentiated from the generated of) the well …


Studies Of Irritant Reactions On Epidermis: The Application Of Energy Dispersive X-Ray Microanalysis, Magnus Lindberg Jan 1990

Studies Of Irritant Reactions On Epidermis: The Application Of Energy Dispersive X-Ray Microanalysis, Magnus Lindberg

Scanning Microscopy

Modern man is exposed to an increasing amount of chemicals in the environment. The skin is a complex tissue with regards to both structure and function. Contact with external stimuli can lead to various responses in the skin depending on the type of stimuli, the dose and time of exposure and the status of the exposed individual. The electron probe microanalytic technique can be used to obtain information on physiological alterations within the skin and especially the epidermis when the normal homeostasis is disturbed by contact with external stimuli. The present paper presents a review of some aspects of contact …


Changes In Rat And Mouse Salivary Glands And Pancreas After Chronic Treatment With Diuretics: A Potential Animal Model For Cystic Fibrosis, Samuel Sagström, Edward B. Mcmillan, Monique Marijianowski, Helmy Mulders, Godfried M. Roomans Jan 1990

Changes In Rat And Mouse Salivary Glands And Pancreas After Chronic Treatment With Diuretics: A Potential Animal Model For Cystic Fibrosis, Samuel Sagström, Edward B. Mcmillan, Monique Marijianowski, Helmy Mulders, Godfried M. Roomans

Scanning Microscopy

Defective transepithelial chloride and water transport is thought to be the cellular basis of the disease cystic fibrosis (CF). Therefore, it was attempted to develop an animal model for this disease by chronically inhibiting transepithelial chloride transport in experimental animals by long term treatment with high doses of diuretics. In the present study, changes in the salivary glands and pancreas after such treatment were investigated by X-ray microanalysis and electron microscopy.

Treatment of rats for one month with diuretics caused a significant decrease in chloride and an increase in calcium in the acinar cells of the submandibular gland. This increase …


Correlative Light, Transmission, And High Resolution (Se-I) Scanning Electron Microscopy Studies Of Rhesus Adrenocortical Vascular Morphology, R. P. Apkarian, N. L. L' Hernault Jan 1990

Correlative Light, Transmission, And High Resolution (Se-I) Scanning Electron Microscopy Studies Of Rhesus Adrenocortical Vascular Morphology, R. P. Apkarian, N. L. L' Hernault

Scanning Microscopy

A detailed correlative morphologic description using light microscopy (LM), transmission electron microscopy (TEM) and high resolution SE-I scanning electron microscopy (SEM) was conducted on the capillary endothelium of the zona-fasciculata (Z-F) in juvenile male rhesus monkeys. The glucocorticoid synthesis and release phenomena, associated with stress stimulated release of adrenocorticotropic hormone (ACTH) via the hypothalamic-pituitary axis, intimately involves capillaries of the Z-F. A comprehensive study of all the ultrastructural features implicated in the transendothelial uptake of steroidogenic precursors and release of glucocorticoids in perfused rhesus adrenals has not previously been made. This report presents correlative images of transendothelial openings that include …


Comparative Analysis Of The Proliferative Response Of The Rat Urinary Bladder To Sodium Saccharin By Light And Scanning Electron Microscopy And Autoradiography, Samuel M. Cohen, Maria J. Fisher, Takao Sakata, Martin Cano, Gerald P. Schoenig, Clifford I. Chappel, Emily M. Garland Jan 1990

Comparative Analysis Of The Proliferative Response Of The Rat Urinary Bladder To Sodium Saccharin By Light And Scanning Electron Microscopy And Autoradiography, Samuel M. Cohen, Maria J. Fisher, Takao Sakata, Martin Cano, Gerald P. Schoenig, Clifford I. Chappel, Emily M. Garland

Scanning Microscopy

Three methods used to detect proliferative changes in the rat urothelium, light microscopy, scanning electron microscopy, and autoradiography, were compared for their sensitivity in detecting changes produced by administration of sodium saccharin. Weanling male F344 rats were fed sodium saccharin as 0, 3, 5, or 7.5% of the diet, and the bladders were evaluated after 4, 7, and 10 wks of feeding. Light microscopic changes and an increase in labeling index were seen at all time points in rats fed 7.5 % sodium saccharin, but not at the lower doses. A slight increase in labeling index was also observed at …


9th Biennial Cheese Industry Conference, Various Authors Jan 1990

9th Biennial Cheese Industry Conference, Various Authors

Cheese Industry Conference

No abstract provided.


1989-1990 Annual Report, Various Authors Jan 1990

1989-1990 Annual Report, Various Authors

Annual Reports

No abstract provided.


Economic Impact Of Proposed Public Land Grazing Fee, Darwin Nielsen Jan 1990

Economic Impact Of Proposed Public Land Grazing Fee, Darwin Nielsen

Economic Research Institute Study Papers

No abstract provided.


Sage Grouse Status And Recovery Plan For Strawberry Valley, Utah, United States Department Of Agriculture, Forest Service Jan 1990

Sage Grouse Status And Recovery Plan For Strawberry Valley, Utah, United States Department Of Agriculture, Forest Service

Wildlife Conservation and Management

Since 1939, an estimated 3,000 sage grouse in Strawberry Valley, UT, have declined to some 180 birds, mainly because of reservoir construction and eradication of big sagebrush to promote livestock forage. A 4-year study of numbers and movements of radio-tagged grouse has provided the basis for a recovery program calling for rejuvenation of big sagebrush and forbs important to grouse, replacement of mating grounds lost to human activities, consideration of sage grouse biology in management decisions, and formation of a sage grouse recovery team.


Preparing Garden Soil, Duane Hatch Jan 1990

Preparing Garden Soil, Duane Hatch

All Archived Publications

No abstract provided.


Pine Hollow Exclosures: Effect Of Browsing On An Aspen Community Sprayed With 2, 4-D, United States Department Of Agriculture, Forest Service Jan 1990

Pine Hollow Exclosures: Effect Of Browsing On An Aspen Community Sprayed With 2, 4-D, United States Department Of Agriculture, Forest Service

Forestry

The Pine Hollow aspen (Populus tremuloides) exclosures on the Ashley National Forest in eastern Utah were sampled in 1984, 19 years after they were established. The effects of 2, 4-D, wildlife, and cattle on plant succession were evaluated. Two exclosures were used to protect the sprayed area from (1) all animal use and (2) only livestock use. A third sprayed area was left open for use by all animals. The aspen overstory was killed as a result of spraying, with sufficient reproduction occurring to restock the stand. However, animal use drastically altered the aspen reproduction, as well as the understory …


Assessment Of Nongame Bird Habitat Using Forest Survey Data, United States Department Of Agriculture, Forest Service Jan 1990

Assessment Of Nongame Bird Habitat Using Forest Survey Data, United States Department Of Agriculture, Forest Service

Wildlife Conservation and Management

Forest Survey data have potential for use in obtaining information on the condition and diversity of the Nation's forest resources relevant to wildlife habitat that is needed for planning and monitoring at State and regional levels. In this study, Forest Survey data were used to assess nongame bird habitat potential based on food and shelter requirements on 24 plots. These assessments were then evaluated using bird numbers. Results of the analyses showed some correlation of bird numbers with tree canopy variables, and illustrate the potential for using Forest Survey data for wildlife habitat assessment, for identifying opportunities to improve habitat …


Bird Populations In And Adjacent To A Beaver Pond Ecosystem In Idaho, United States Department Of Agriculture, Forest Service Jan 1990

Bird Populations In And Adjacent To A Beaver Pond Ecosystem In Idaho, United States Department Of Agriculture, Forest Service

Wildlife Conservation and Management

We compared breeding bird populations and community organization between a beaver pond habitat dominated by willows (Salix spp.) and an adjacent nonwillow riparian habitat on Summit Creek in east-central Idaho. For the previous 14 years both habitats had been protected from livestock grazing by a fenced excloser (122-ha). Bird populations were determined by spot-mapping on 9-ha plots in spring 1989. Structural (physiognomic) differences in vegetation between the two habitats and the availability of impounded water on the beaver pond site were reflected in associated breeding bird populations. Total bird density in the beaver pond habitat was three times that of …


Evaluating Growth & Maternal Traits Of Beef Cattle, Nyle J. Matthews Jan 1990

Evaluating Growth & Maternal Traits Of Beef Cattle, Nyle J. Matthews

All Archived Publications

No abstract provided.


Conditioned Flavor Aversion: A Mechanism For Goats To Avoid Condensed Tannins In Blackbrush, Frederick D. Provenza, Elizabeth A. Burritt, T. P. Clausen, J. P. Bryant, P. B. Reichardt, Roberto A. Distel Jan 1990

Conditioned Flavor Aversion: A Mechanism For Goats To Avoid Condensed Tannins In Blackbrush, Frederick D. Provenza, Elizabeth A. Burritt, T. P. Clausen, J. P. Bryant, P. B. Reichardt, Roberto A. Distel

Behavioral Education for Human, Animal, Vegetation, and Ecosystem Management (BEHAVE)

It has been hypothesized that herbivores instinctively avoid tannin-containing plant parts in response to the adverse effects of tannins on forage digestion. However, we found that goats learned to avoid condensed tannins (CTs) from blackbrush current season's growth by associating the flavor of foods containing CTs with aversive postingestive consequences. The aversive consequences experienced by goats apparently are not related to digestion inhibition and may depend on the structure of CTs and on how CTs are bound with other cell constituents. These observations suggest several areas of inquiry related to the interaction between CTs and herbivores. A better understanding of …


Cody Record Of Decision And Approved Resource Management Plan, United States Department Of The Interior, Bureau Of Land Management Jan 1990

Cody Record Of Decision And Approved Resource Management Plan, United States Department Of The Interior, Bureau Of Land Management

Record of Decisions (WY)

This document records the decision made by the Bureau of Land Management (BLM) for managing approximately 891,600 acres of public land surface and 1,508,200 acres of federal mineral estate administered by the Bureau of Land Management in the Cody Resource Area.


Anasazi Basketmaker: Papers From The 1990 Wetherill-Grand Gulch Symposium, Victoria M. Atkins, Lisa Mcclanahan Jan 1990

Anasazi Basketmaker: Papers From The 1990 Wetherill-Grand Gulch Symposium, Victoria M. Atkins, Lisa Mcclanahan

Elusive Documents

No abstract provided.


Grasshoppers In Utah: General Biology, Edward W. Evans Jan 1990

Grasshoppers In Utah: General Biology, Edward W. Evans

All Archived Publications

No abstract provided.