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Strontium And Bromide As Tracers In X-Ray Microanalysis Of Biological Tissue, Joanna Wroblewski, Samuel Sagström, Helmy Mulders, Godfried M. Roomans Oct 1989

Strontium And Bromide As Tracers In X-Ray Microanalysis Of Biological Tissue, Joanna Wroblewski, Samuel Sagström, Helmy Mulders, Godfried M. Roomans

Scanning Microscopy

Since energy dispersive X-ray microanalysis cannot distinguish between isotopes of the same element, alternative methods have to be used to get information similar to that obtained in experiments with radioactive tracers. In the present study, strontium was used as a tracer for calcium, and bromide as a tracer for chloride. Rats were injected with strontium chloride in vivo, and the uptake of strontium in the acinar cells of the submandibular gland was studied. Eventually a Sr/Ca ratio of 0.3 was reached. In some animals, secretion of mucus had been elicited by stimulation with isoproterenol 4 h prior to injection …


Bone Lining Cells: Structure And Function, Scott C. Miller, Louis De Saint-Georges, Beth M. Bowman, Webster S. S. Jee Oct 1989

Bone Lining Cells: Structure And Function, Scott C. Miller, Louis De Saint-Georges, Beth M. Bowman, Webster S. S. Jee

Scanning Microscopy

Bone lining cells (BLC's) cover inactive (nonremodeling) bone surfaces, particularly evident in the adult skeleton. BLC's are thinly extended over bone surfaces, have flat or slightly ovoid nuclei, connect to other BLC's via gap junctions, and send cell processes into surface canaliculi. BLC's can be induced to proliferate and differentiate into osteogenic cells and may represent a source of "determined" osteogenic precursors. BLC's and other cells of the endosteal tissues may be an integral part of the marrow stromal system and have important functions in hematopoiesis, perhaps by controlling the inductive microenvironment. Because activation of bone remodeling occurs on inactive …


Backscattered Electron Imaging Using Single Crystal Scintillator Detectors, R. Autrata Oct 1989

Backscattered Electron Imaging Using Single Crystal Scintillator Detectors, R. Autrata

Scanning Microscopy

The image obtained by the detection of backscattered electrons (BSE) becomes an indispensable complement to the correct interpretation and more precise reconstruction of the surface of the specimen and its material composition. The BSE are carriers of information which is dependent on their angular and energy distribution. The choice of a certain type of BSE and their efficient detection make it possible to record the desired information with a different grade of quality. The knowledge of the angular and energy distribution of BSE is necessary for the adjustment of the correct position of the BSE detector with regard to the …


Osteoclast Features Of Cells That Resorb Demineralized And Mineral-Containing Bone Implants In Rats, Cedo M. Bagi, Scott C. Miller Oct 1989

Osteoclast Features Of Cells That Resorb Demineralized And Mineral-Containing Bone Implants In Rats, Cedo M. Bagi, Scott C. Miller

Scanning Microscopy

The comparative temporal tissue response to demineralized bone matrix powder (DBP) and devitalized mineral containing bone powder (MCP) implanted subcutaneously in rats was studied. The tissue response to implanted DBP followed the well described endochondral osteogenic pathway and included the appearance of osteoblasts and osteoclasts. On the other hand, implanted MCP resulted in the appearance of a large population of giant cells that resorbed the implants. At later times (3-4 weeks), most of the cells in the MCP implants appeared as typical foreign body giant cells with extensive membrane foldings, usually away from bone surface. Some cells did, however, have …


Practical Aspects Of Automatic Orientation Analysis Of Micrographs, N. K. Tovey, P. Smart, M. W. Hounslow, X. L. Leng Oct 1989

Practical Aspects Of Automatic Orientation Analysis Of Micrographs, N. K. Tovey, P. Smart, M. W. Hounslow, X. L. Leng

Scanning Microscopy

Techniques to analyse the orientation of particulate materials as observed in the scanning electron microscope are reviewed in this paper. Emphasis is placed on digital imaging, processing, and analysis methods, but many secondary electron images are not amenable to traditional image processing as adequate thresholding is often difficult to achieve. Evaluation of the intensity gradient at each pixel offers an alternative approach, and this method is described in detail including the latest developments to generalize the technique. Practical points in the acquisition, processing and analysis of the images are considered and several images, including both synthetically generated and actual back-scattered …


Structural And Compositional Changes In Aging Bone: Osteopenia In Lumbar Vertebrae Of Wistar Female Rats, M. Silbermann, M. Safadi, D. Schapira, I. Leichter, R. Steinberg Oct 1989

Structural And Compositional Changes In Aging Bone: Osteopenia In Lumbar Vertebrae Of Wistar Female Rats, M. Silbermann, M. Safadi, D. Schapira, I. Leichter, R. Steinberg

Scanning Microscopy

Changes in vertebral bone mineral content and density during aging were quantified in female Wistar rats. This study represents a longitudinal follow up utilizing single photon absorptiometry for the measurement of bone mineral content (BMC), quantitative computed tomography (OCT) for the measurement of bone mineral density (BMD), and image analysis histomorphometry for the measurement of trabecular bone volume (TBV) and bone cortical area (BCA). The above measurements were accompanied by biochemical assays of calcium concentrations in the respective bones. All aging animals experienced significant decreases in BMC, BMD, TBV, BCA and in the calcium content of their bones. The above …


Microprobe Analysis Of Element Distribution In Bovine Extracellular Matrices And Muscle, M. B. Engel, H. R. Catchpole Oct 1989

Microprobe Analysis Of Element Distribution In Bovine Extracellular Matrices And Muscle, M. B. Engel, H. R. Catchpole

Scanning Microscopy

The concentrations of some essential elements, Na, K, P, S and Cl were determined by microprobe analysis in bovine extracellular matrices of cartilage, tendon and elastic tissue (ligamentum nuchae) and in muscle cells. The values for the different tissues were compared and related to the blood electrolyte concentrations. Among the connective tissues the highest Na and lowest Cl values were found for cartilage which bears a high negative charge. The lowest concentrations of these elements occurred in elastic tissue which is relatively non-polar. In the three extracellular matrices sodium levels exceeded potassium. In myofibers potassium was the major cation at …


Bacillus-Shaped Deposits Composed Of Hexahedrally Based Crystals In Human Dental Calculus, T. Kodaka, A. Hirayama, K. Miake, S. Higashi Oct 1989

Bacillus-Shaped Deposits Composed Of Hexahedrally Based Crystals In Human Dental Calculus, T. Kodaka, A. Hirayama, K. Miake, S. Higashi

Scanning Microscopy

In human supra- and subgingival calculus, bacillus-shaped deposits showing various rocky-pile forms composed of hexahedrally based crystals were observed by scanning electron microscopy. The crystal size measured approximately 0.1 - 1.5 μm. The electron probe microanalysis always detected calcium, phosphorous, and magnesium. Their molar ratios resembled those of magnesium-containing whitlockite and moreover the crystals also gave the electron diffraction pattern of whitlockite. The bacillus-shaped deposits happened to coexist with the intracellular calcifying microorganisms, furthermore, oral microorganisms partially replaced by the hexahedrally based crystals were found. The crystal deposits were never seen in the surface layers of calculus exposed to the …


Data Acquisition And Presentation In Scanning Nuclear Microprobe Analysis, K. G. Malmqvist, N. E. G. Lövestam, J. Pallon, U. A. S. Tapper Oct 1989

Data Acquisition And Presentation In Scanning Nuclear Microprobe Analysis, K. G. Malmqvist, N. E. G. Lövestam, J. Pallon, U. A. S. Tapper

Scanning Microscopy

The data acquisition is a very important part of the scanning nuclear microprobe instrument. To make full use of the potential of the technique an adequate system for acquiring, storing, processing and presenting the data is a prerequisite. Various principles applied are presented including the list mode approach, which facilitates flexible off-line data processing. As in the case of the electron probe the beam-induced effects in the sample may be substantial and the list mode acquisition can then also be used to monitor and correct for any such effects. A comprehensive system for scanning nuclear microprobe control and data acquisition, …


Quantitative Measurement From Vascular Casts, Ralph G. Kratky, Christine M. Zeindler, Dorian K. C. Lo, Margot R. Roach Oct 1989

Quantitative Measurement From Vascular Casts, Ralph G. Kratky, Christine M. Zeindler, Dorian K. C. Lo, Margot R. Roach

Scanning Microscopy

A review of quantitative measurements show casting materials shrink from 0.2 - 20% and have viscosities ranging from 1.4 - 100,000 centipoise. Blood vessels have highly variable mechanical properties. Some microvessels are very stiff having little change in dimensions with pressure. Larger vessels generally change diameter significantly but show highly variable changes in length with pressure. Perfusion fixation does not fix the dimensions of blood vessels. Dog carotid arteries well fixed with glutaraldehyde at physiologic dimensions retain ≈20% of their elastic recoil circumferentially and ≈30% longitudinally. We recommend vascular casting as a method of accurately measuring the vasculature if care …


Surface Heterogeneity Of Tumor Cells And Changes Upon Ionizing Radiation, Z. Somosy, Orsolya Csuka, Tamara Kubasova, J. Kovács, G. J. Köteles Oct 1989

Surface Heterogeneity Of Tumor Cells And Changes Upon Ionizing Radiation, Z. Somosy, Orsolya Csuka, Tamara Kubasova, J. Kovács, G. J. Köteles

Scanning Microscopy

Heterogeneous distribution of surface domains is a characteristic feature of the tumor cell surface and the distribution differs from that of normal cells. During the malignant transformation the heterogeneity may change or disappear. Cell lines with various metastasizing capacities show different distributions of membrane domains or other differences in membrane or surface organization. We have demonstrated that the amount and distribution of negatively charged sites of B 16 melanoma membranes changed upon ionizing radiation (X-ray, 60Co-gamma). In the case of the P 388 lymphoma, however, only the amount of negatively charged sites change after irradiation, the distribution remains unaltered. …


Oxalate Crystallization In The Kidney In The Presence Of Hyperuricemia, Shinshi Noda, Kenichi Hayashi, Kousaku Eto Oct 1989

Oxalate Crystallization In The Kidney In The Presence Of Hyperuricemia, Shinshi Noda, Kenichi Hayashi, Kousaku Eto

Scanning Microscopy

It has been a long time since uric acid was suggested to be a promoting factor in calcium oxalate stones, and a number of in vitro studies have been carried out on the relationship between uric acid or urate and calcium oxalate.

Concerning in vivo studies, urate or calcium oxalate stone-forming diets were given alone in most cases, and diets that induce formation of stones with different composition have not been given in combinations. We administered a low-concentration oxalemic diet, and a mixed diet containing oxalic acid and uric acid, and biochemically and histologically studied the effects of oxalate and …


The Physical State Of Potassium In The Human Lymphocyte: A Review, William Negendank Oct 1989

The Physical State Of Potassium In The Human Lymphocyte: A Review, William Negendank

Scanning Microscopy

Studies of the effects of chemical potential, temperature, and metabolic perturbation on static ion contents, kinetics of the approach to equilibrium, and kinetics of ionic self-exchange in human lymphocytes are reviewed. The results contradict the classical concept of cell ion and water physiology, the membrane-osmotic, pump-leak theory, and are re-interpreted by an adsorption model of the cell. In this model, most of cell water exists in a physical state sufficiently ordered to reduce the partition function of dissolved ions, and most of cell potassium is associated with fixed charges on macromolecules. Competing adsorption of potassium and sodium is cooperative and …


Gastrointestinal Surface Changes: Interpretation Problems And Indexing Possibilities (A Review), C. J. Pfeiffer, O. Bulbena Oct 1989

Gastrointestinal Surface Changes: Interpretation Problems And Indexing Possibilities (A Review), C. J. Pfeiffer, O. Bulbena

Scanning Microscopy

The purpose of this review on state-of-the-art and new perspectives on the use of scanning electron microscopy (SEM) in gastrointestinal pathology is to discuss the possibility of developing an index for quantitatively grading mucosal epithelial injury. This topic is reviewed within the framework of ulcer indices previously developed for gross lesions, where analogous problems exist, and in relation to the transmission electron microscope staging of epithelial cell pathology. If such an index could be developed it would increase objectivity and standardization of data analysis from laboratory to laboratory, and would allow for quantitative and statistical analysis of morphometric data. It …


Morphology And Chemical Composition Of Dental Calculi Mainly Composed Of Whitlockite, Toshiro Sakae, Hirotsugu Yamamoto, Hiroyuki Mishima, Takashi Matsumoto, Yukishige Kozawa Oct 1989

Morphology And Chemical Composition Of Dental Calculi Mainly Composed Of Whitlockite, Toshiro Sakae, Hirotsugu Yamamoto, Hiroyuki Mishima, Takashi Matsumoto, Yukishige Kozawa

Scanning Microscopy

The morphology and chemical composition of two subgingival calculus samples, which were composed of magnesium-whitlockite with a Mg/Ca molar ratio of approximately 0.1 as shown by X-ray powder diffraction, were analyzed semiquantitatively using energy-dispersive spectroscopy (EDS) combined with scanning electron microscopy (SEM). The Ca/P molar ratio values for 33 EDS-analyzed materials ranged from 1.24 to 2.03 with an average of 1.49, and the (Mg+Ca)/P molar ratio values ranged from 1.43 to 2.28 with an average of 1.63. The average Mg/Ca molar ratio was 0.10, a value very close to that obtained by X-ray diffraction analysis.

The EDS-analyzed materials were grouped …


Scanning Tunneling Microscopy And Fabrication Of Nanometer Scale Structures At The Liquid-Gold Interface, J. Schneir, H. H. Harary, J. A. Dagata, P. K. Hansma, R. Sonnenfeld Oct 1989

Scanning Tunneling Microscopy And Fabrication Of Nanometer Scale Structures At The Liquid-Gold Interface, J. Schneir, H. H. Harary, J. A. Dagata, P. K. Hansma, R. Sonnenfeld

Scanning Microscopy

The Scanning Tunneling Microscope (STM) can image gold surfaces covered with a variety of liquids. This paper reviews the results obtained using the STM to image gold surfaces covered with liquid. These results include the creation of 10 nm structures, images of the electrochemical process of electroplating, and the production of atomically flat Au (111) surfaces. We conclude that in the future STM will find further application in the area of nanostructure fabrication and electrochemistry. The trend in the field is toward greater control of the electrochemical environment.


Pesticide Movement And Water Management, Majid Ehteshami, Richard C. Peralta Oct 1989

Pesticide Movement And Water Management, Majid Ehteshami, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Agricultural chemicals are essential components of agricultural production systems in the United states. Pesticides control weeds, insects, and have had an important role in increasing agricultural productivity in the last 50 years, despite diminishing crop land acreage. The benefits of chemicals use options in agriculture must be balanced against potential contamination of surface water and ground water resources. This study shows the effect of water management practices on pesticide movement and its potential pollution to ground water. It indicates that careful use of pesticides, water management practices and irrigation system design alternatives could cause a major reduction in ground water …


Cation Nuclear Magnetic Resonance (Nmr). 7li- And 23na-Nmr Results Obtained With Human Erythrocytes, Jan F. M. Post Sep 1989

Cation Nuclear Magnetic Resonance (Nmr). 7li- And 23na-Nmr Results Obtained With Human Erythrocytes, Jan F. M. Post

Scanning Microscopy

A short discussion of practical results and theoretical aspects of nuclear magnetic resonance (NMR) on intracellular monovalent cations is presented. 7Li- and 23Na-NMR relaxation studies on human erythrocytes are described which indicate that lithium and sodium ions are essentially free inside the cell. However, there is a contribution to transverse relaxation originating from cations diffusing through electric field gradients imposed by the cytoskeleton, which is reflected in the NMR line shape. 39K-NMR results obtained by other authors for intracellular potassium are compared with the 7Li- and 23Na-NMR results presented here. The few 39K-NMR results …


Small Spacecraft For Low-Cost Planetary Missions, K.J. Cole, H. Feingold, J. Mcadams, M.L. Stancati, J.R. French Sep 1989

Small Spacecraft For Low-Cost Planetary Missions, K.J. Cole, H. Feingold, J. Mcadams, M.L. Stancati, J.R. French

Small Satellite Conference

Small low-cost spacecraft offer the opportunity to carry out a variety of planetary exploration missions at modest cost as part of a sustained program. This study identifies scientifically valuable missions of modest cost that can be carried out by modifications of a single spacecraft design. These missions lend themselves to a continuing program of essentially constant funding level. Such a program could involve several launches spread over a period of 10 to 15 years at roughly two-year intervals. The stability offered by relatively constant funding, frequent launches, and the return of data in a more nearly constant fashion than is …


Simultaneous Micro-Characterization Of The Superconducting And Structural Properties Of High-Tc Superconducting Films, R. P. Huebener, R. Gross Sep 1989

Simultaneous Micro-Characterization Of The Superconducting And Structural Properties Of High-Tc Superconducting Films, R. P. Huebener, R. Gross

Scanning Microscopy

Important information on the local values of the critical temperature and the critical current density in high-Tc superconducting films is obtained by low-temperature scanning electron microscopy (LTSEM). The imaging principle of LTSEM is based on the local beam-induced heating effect and the detection of a voltage response signal in the current-biased specimen film. During the scanning process the sample is mounted on a low-temperature stage the temperature of which is electronically stabilized at some specific value in the range of interest. The local superconducting quantities measured by LTSEM can be correlated with the microstructure of the specimen film investigated …


Population Dynamics And Management Of Deer In Wisconsin, Keith R. Mccaffery Sep 1989

Population Dynamics And Management Of Deer In Wisconsin, Keith R. Mccaffery

Wildlife Damage Management Conference

Management of deer in Wisconsin is affected by a combination of biological and environmental factors. In the Northern Forest, winter severity dramatically affects annual survival and recruitment. However, deer density goals here are above "I" carrying capacity. Thus, minor errors in harvest management are in part compensated by herd responses. Deer in the farmland areas of the state are maintained at goals that for the most part are below "I" carrying capacity. Errors in harvest management are magnified in farmland because herd responses are not compensatory. Therefore, the harvest quotas for antlerless deer must be more precise in our farmland …


Economic Impact And Control Of Wading Birds At Arkanas Minnow Ponds, Michael D. Hoy, Jeffery W. Jones, Albert E. Bivings Sep 1989

Economic Impact And Control Of Wading Birds At Arkanas Minnow Ponds, Michael D. Hoy, Jeffery W. Jones, Albert E. Bivings

Wildlife Damage Management Conference

Esophageal/stomach contents of 172 little blue herons (Egretta caerulea), great egrets (Casmerodius albus), snowy egrets (Egretta thula), and great blue herons (Ardea herodias) were analyzed to estimate their consumption of golden shiners. Mean and maximum number of golden shiners consumed/bird, as well as the mean total length of golden shiners consumed by each wading bird species was determined. Loss estimates varied by wading bird species and ranged from $0.10 - $1.12/bird/feeding. Loss estimates reflect the severity of problems with wading birds on minnow ponds and the need to reduce losses by use …


The Usda-Aphis-Adc Program In The United States, Bobby R. Acord Sep 1989

The Usda-Aphis-Adc Program In The United States, Bobby R. Acord

Wildlife Damage Management Conference

The ADC program was transferred to the U.S. Department of Agriculture, Animal and Plant Health Inspection Service in 1986. Shortly after the transfer, the Secretary of Agriculture established the National Animal Damage Control Advisory Committee (NADCAC). Current and future issues facing ADC are discussed in the context of NADCAC recommendations.


Microscopy Analysis Of Dental Titanium Casting Investment Materials, H. J. Mueller Sep 1989

Microscopy Analysis Of Dental Titanium Casting Investment Materials, H. J. Mueller

Scanning Microscopy

Scanning electron microscopy (SEM) analysis and qualitative energy dispersive x-ray microanalysis (EDS) of investment materials for dental titanium casting were performed. Two commercial investment materials, Ohara and Castmatic, and an experimental zirconia material were analyzed. The microstructural constituents and the unfired and fired structures were included. Larger refractory particles and matrix embedding smaller particles were observed with each material. Detection of aluminum, silicon, magnesium, zirconium and oxygen provided a basis to reason the presence of alumina (Al2O3), silica (SiO2), magnesia (MgO), and zirconia (ZrO2). Hence, Ohara contained quartz and an alumino-silicate, Castmatic …


Ecologically Sensitive Management Options For Bats, Paul B. Robertson Sep 1989

Ecologically Sensitive Management Options For Bats, Paul B. Robertson

Wildlife Damage Management Conference

Over the past decade, there has been a dramatic, positive shift in the public image of bats in the United States (Tuttle 1988a). This shift is particularly impressive in light of the inappropriate and poor public image that bats have suffered in most western nations in the last century. Over the past decade, a sizable segment of the U.S. public, as well as local, state and national officials, have been educated to the ecological and economic value of bats which results from their insectivory and plant pollination activities (Olkowski and Olkowski 1989, Tuttle 1988b). The fact that they pose a …


Donkeys For Predation Control, Jeffrey S. Green Sep 1989

Donkeys For Predation Control, Jeffrey S. Green

Wildlife Damage Management Conference

Donkeys (Equus assinus) are described and their availability discussed. Key points which appear important in successfully using a donkey for reducing predation on livestock are presented.


Beaver And Beaver Dam Removal In Wisconsin Trout Streams, Larry Dickerson Sep 1989

Beaver And Beaver Dam Removal In Wisconsin Trout Streams, Larry Dickerson

Wildlife Damage Management Conference

Beaver (Castor canadensis) dam building activities create many longterm affects on stream ecosystems. Beaver dams may negatively influence trout fisheries by creating physical barriers to spawning areas, increasing sediment retention, and increasing water temperatures. The U.S. Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) Animal Damage Control (ADC) program in Wisconsin, entered into cooperative agreements with the Wisconsin Department of Natural Resources (WDNR) and the U.S. Forest Service (USFS) on the Nicolet National Forest from June through September, 1988, to remove beaver and beaver dams from priority classed trout streams. Four hundred and eight beaver …


Population Dynamics And Harvest Response Of Beaver, Neil F. Payne Sep 1989

Population Dynamics And Harvest Response Of Beaver, Neil F. Payne

Wildlife Damage Management Conference

"For when we speak of the fur trade, we mean the beaver trade. Other furs were handled; others -- notably the rich sea otter -- were more valuable by far. But the beaver was the root and core of the trade... Many men died, a continent was explored, an indigenous [human] race degraded and its culture crushed; all because beaver fur, with its tiny barbs, felted up better than any other" (Berry 1961:18).


Fertility Control As A Tool For Regulation Of Wildlife Populations, U. S. Seal Sep 1989

Fertility Control As A Tool For Regulation Of Wildlife Populations, U. S. Seal

Wildlife Damage Management Conference

Biological control of reproduction and fertility is a normal part of the life history of all organisms. Control mechanisms allow timing of reproduction with respect to age, time of day, season, and other periodic environmental events. Further modulation can occur with variations in temperature, rainfall, nutrition, and health status. Interactions with other members of the species, ranging from pherohormonal stimulation of estrus to social delay of puberty and breeding to infanticide, provide further constraints upon fertility and recruitment. All of these processes ultimately act through molecular neuroendocrine mechanisms that are under genetic control and are subject to natural selection and …


The Role Of Private Enterprise In Wildlife Damage Control, Lynn Braband Sep 1989

The Role Of Private Enterprise In Wildlife Damage Control, Lynn Braband

Wildlife Damage Management Conference

In addressing the role of private enterprise in wildlife damage control, I will not be bringing the final word or a comprehensively exhaustive report. Rather, I will be presenting some perspectives as the representative of a firm with extensive involvement with wildlife damage control as a business. My comments will be divided into why, what, how, and the future.