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A Comparative Scanning Electron Microscopic View Of The Integument Of Domestic Mammals, W. Meyer, K. Neurand Oct 1986

A Comparative Scanning Electron Microscopic View Of The Integument Of Domestic Mammals, W. Meyer, K. Neurand

Scanning Microscopy

Scanning electron microscopy (SEM) demonstrates efficiently species-specific differences of hairy skin (integumentum commune) of domestic mammals (pig, cat, dog, horse, cattle, sheep, goat). This technique is very helpful in characterizing the typical structural features of the epidermal layers, the arrangement of the collagen fibre bundles and the elastic fibre network in the dermis, the external and internal construction of hair follicles and hair shafts, and the functional development of skin glands. It is also possible to observe certain domestication effects, especially where the hair coat is concerned.

SEM supplements the knowledge about the integument as available from conventional transmission electron …


Effects Of High Energy Particle (Hze) Radiation On The Distal Lung, David P. Penney, Delbert E. Philpott, Wayne A. Rosenkrans, Robert A. Cooper Jr. Oct 1986

Effects Of High Energy Particle (Hze) Radiation On The Distal Lung, David P. Penney, Delbert E. Philpott, Wayne A. Rosenkrans, Robert A. Cooper Jr.

Scanning Microscopy

Major sources of concern for manned space travel are the effects of high energy particle (HZE) radiation on various biological systems, and the consequences of major solar activity. To date, considerable attention has been directed toward HZE-induced alterations both on non-dividing systems, such as the retina, cornea and brain, and on dividing systems, such as the gut and testis. This paper is focused on the morphologically detectable late-occurring alterations in the distal lung, and toward a comparison of the changes with those induced by x -irradiation. Briefly, the salient alterations involve an increase in 1) the width of the septal …


Vasospastic Phenomena On The Luminal Replica Of Rat Brain Vessels, Enrico D. F. Motti, Hans-Georg Imhof, Jesus Martinez Garza, Gazi M. Yasargil Oct 1986

Vasospastic Phenomena On The Luminal Replica Of Rat Brain Vessels, Enrico D. F. Motti, Hans-Georg Imhof, Jesus Martinez Garza, Gazi M. Yasargil

Scanning Microscopy

Strikingly localized ring-like constrictions (other than sphincters, cushions and offshoot furrows) have appeared on the casted vessels of some of our preparations. Morphology of the phenomena reveals diverse degree of active contraction of the vessel wall, ranging from corrugation of the luminal surface to near severance of the acrylic cast. Distribution of the vasospastic phenomena reveals as particularly affected the arteries in the diameter range between 25 and 75 μm, that belong either to intra-arterial anastomoses between the branches of each of the three major cerebral arteries or to their terminal junctions in the border zones (inter-arterial anastomoses). Among the …


Structure-Function Relationships In Radiation-Induced Cell And Tissue Lesions: Special References To The Contributions Of Scanning Electron Microscopy And Hematopoietic Tissue Responses, T. M. Seed Oct 1986

Structure-Function Relationships In Radiation-Induced Cell And Tissue Lesions: Special References To The Contributions Of Scanning Electron Microscopy And Hematopoietic Tissue Responses, T. M. Seed

Scanning Microscopy

Contributions of scanning electron microscopy to the field of radiation biology are briefly reviewed and presented in terms of an overall goal to identify and characterize the structural features of radiation-induced lesions in vital cell and tissue targets. In the context of "lesion" production, the major radiation-elicited response sequences, the types and nature of measured end points, and governing temporal and radiobiological parameters are discussed and illustrated by using results derived from both in vitro cell systems and in vivo studies that measured tissue responses from various organ systems (respiratory, digestive, circulatory, and central nervous systems). Work in our laboratory …


Scanning Electron Microscopic Observations On Differentiation And Maintenance Of Photoreceptor Cells In Vitro, R. J. Ulshafer, P. E. Spoerri, C. B. Allen, K. C. Kelley Oct 1986

Scanning Electron Microscopic Observations On Differentiation And Maintenance Of Photoreceptor Cells In Vitro, R. J. Ulshafer, P. E. Spoerri, C. B. Allen, K. C. Kelley

Scanning Microscopy

Scanning electron microscopy was performed on cell cultures of embryonic and post-hatch chick retinas co-cultured with optic lobe neurons or in medium that had been pre-conditioned with optic lobe cells. The culture medium consisted of Eagles Basal Medium supplemented with glucose, fetal calf serum, glutamine and bicarbonate. Application of colchicine (Sμg/ml) to the cultures, encouraged the dissociation of retinal cell rosettes and optic lobe neuron aggregates, thereby allowing us to examine differentiation of isolated photoreceptor cells. Over time, developing photoreceptor cells gradually took on the morphological characteristics of rods and cones in the post-hatch chick: cells were polarized having a …


Scanning Electron Microscopic Analysis Of Intraocular Ossification In Advanced Retinal Disease, Clark B. Allen, Robert J. Ulshafer, E. Ann Ellis, James C. Woodard Oct 1986

Scanning Electron Microscopic Analysis Of Intraocular Ossification In Advanced Retinal Disease, Clark B. Allen, Robert J. Ulshafer, E. Ann Ellis, James C. Woodard

Scanning Microscopy

Chicken eyes from congenic blind (rd/rd) animals showing early, intermediate, and final stages of ossification, similar to the phthisis bulbi condition in man, were examined using scanning and transmission electron microscopy as well as light microscopy and X-ray microanalysis. Early stages of ossification were devoid of mineralized calcium apatite while intermediate and end stages of the disorder contained large amounts of calcium and phosphorus. This process resulted in metaplastic bone formation. An intact Bruch's membrane appeared to separate the choroid from the degenerated pigment epithelium and the developing bone suggesting that its possible origin was metaplasia of the retinal pigment …


Fine Structural Observations Of The Apical Organ In The Larva Of Polygordius (Annelida: Polychaeta), Terry Sensenbaugh, Ake Franzén Oct 1986

Fine Structural Observations Of The Apical Organ In The Larva Of Polygordius (Annelida: Polychaeta), Terry Sensenbaugh, Ake Franzén

Scanning Microscopy

The larva of the archiannelid Polygordius was studied using light microscopy (LM), scanning ( SEM) and transmission electron microscopy (TEM). The embryo of Polygordius develops into a large trochophore larva adapted to planktonic swimming and feeding. The young larva is characterized by the presence of an approximately hemispherical episphere including a basal prototroch and a well-developed apical organ which lacks a central ciliary tuft. The conical hyposphere is smaller and contains the metatrochophore segments. The apical organ of the episphere consists of a large, bulbous mass of cells that project deeply into the spacious blastocoel. Two tentacular knobs and two …


Review Of Statoconia Formation In Birds And Original Research In Chicks (Gallus Domesticus), Cesar D. Fermin, Makoto Igarashi Oct 1986

Review Of Statoconia Formation In Birds And Original Research In Chicks (Gallus Domesticus), Cesar D. Fermin, Makoto Igarashi

Scanning Electron Microscopy

This paper reviews published materials on statoconia formation in birds, and emphasizes works dealing with the embryonic chick (Gallus domesticus) saccule and utricule. Histological, biochemical and histochemical aspects of forming statoconial membranes and statoconial crystals of mammals are included. Results from our work with chick embryos permitted us to conclude that statoconia probably do not form by seeding of a subunit around central core. Instead, immature statoconia may emerge already formed, from a segmenting mass of organic material that seems to be secreted by the supporting cells of the saccular and utricular maculae. Crystallization of each statoconium may …


Scanning Electron Microscopy Of Eggshells Of Contemporary Reptiles, Mary J. Packard, Karl F. Hirsch Oct 1986

Scanning Electron Microscopy Of Eggshells Of Contemporary Reptiles, Mary J. Packard, Karl F. Hirsch

Scanning Electron Microscopy

Eggshells of contemporary turtles and squamate reptiles (lizards, snakes, and the tuatara) are either flexible or rigid, and usually are composed of both a fibrous shell membrane and an overlying calcareous layer. The calcareous layer of turtle eggs is calcium carbonate in the form of aragonite, whereas the crystalline material of squamate eggs generally is calcite. Both rigid and flexible shells of turtle eggs are composed of individual building blocks or shell units. Shell units of rigid shells abut tightly, and few pores penetrate the calcareous layer. In contrast, flexible shells exhibit large numbers of spaces or pores in the …


Early Scanning Electron Microscopic Studies Of Hard Tissue Resorption: Their Relation To Current Concepts Reviewed, A. Boyde, S. J. Jones Oct 1986

Early Scanning Electron Microscopic Studies Of Hard Tissue Resorption: Their Relation To Current Concepts Reviewed, A. Boyde, S. J. Jones

Scanning Microscopy

This paper highlights some observations made by the authors in SEM studies of hard tissue resorption and considers their significance in relation to current concepts. All mammalian mineralised tissues may undergo physiological resorption, the resulting surface reflecting the density of mineralisation and the organic matrix chemistry, organisation and orientation. Resorption-repair coupling may follow the resorption of any tissue, but SEM studies first noted this process in the case of the dental tissues. The difference between fetal and adult bone formation and resorption provided evidence against the concept of osteocytic osteolysis. SEM stereophotogrammetric methods for the quantitation of individual resorption lacunae …


Studies Of Otoconial Development In A “Giant-Crystal” Strain Of Chicks Using Scanning Electron Microscopy, Polarized Light Microscopy, And X-Ray Crystallography, Joanne Ballarino, Howard C. Howland Oct 1986

Studies Of Otoconial Development In A “Giant-Crystal” Strain Of Chicks Using Scanning Electron Microscopy, Polarized Light Microscopy, And X-Ray Crystallography, Joanne Ballarino, Howard C. Howland

Scanning Electron Microscopy

Otolith formation was studied in a mutant strain of low-fertility Delaware chicks which exhibit an otolithic defect. In all chicks of this strain, otoliths were present as a fused crystal mass which contained abnormally large (giant) otoconia. Studies of the formation of such otoliths during embryonic development revealed that from the very earliest stages the otoconia were much larger than normal, and in the saccular and utricular otoliths formed a fused mass. These results are interpreted as supporting a hypothesis of the de novo formation of giant otoconia in this giant-crystal strain as opposed to the recrystallization hypothesis proposed for …


Chromatid Behavior In Late Mitosis: A Scanning Electron Microscopy Analysis Of Mammalian Cell Lines With Various Chromosome Numbers, D. A. Welter, D. A. Black, L. D. Hodge Oct 1986

Chromatid Behavior In Late Mitosis: A Scanning Electron Microscopy Analysis Of Mammalian Cell Lines With Various Chromosome Numbers, D. A. Welter, D. A. Black, L. D. Hodge

Scanning Electron Microscopy

Chromatid activity during the process of nuclear reformation following metaphase is a period of mitosis where little precise information is available. Nuclear reformation requires that chromosomes, at metaphase and chromatids during anaphase and telophase align, position and associate in a clearly defined sequence to insure the specific design of each nucleus. Four cell lines with chromosome numbers ranging from seven to almost seventy were chosen to determine whether the process of nuclear assembly is the same throughout. Chromosomal alignment at metaphase is found to be radial in all four cell lines. Chromosome positioning is essentially the same in all four, …


Preparation Methods For Light Microscopic And Ultrastructural Studies Of Fetal Rat Bladder, M. Cano, S. L. Johansson, R. B. Wilson, L. B. Ellwein, T. Sakata, S. M. Cohen Oct 1986

Preparation Methods For Light Microscopic And Ultrastructural Studies Of Fetal Rat Bladder, M. Cano, S. L. Johansson, R. B. Wilson, L. B. Ellwein, T. Sakata, S. M. Cohen

Scanning Electron Microscopy

Little is known about in utero urinary bladder embryogenesis and the development of the urothelium of laboratory animals. Previous scanning and transmission electron microscopy studies in rats and mice have indicated that the highly specialized superficial cells of the urothelium complete their differentiation at a very late stage of fetal development or shortly after birth. Limitations in methodology in the past have precluded extensive examination of earlier stages of bladder development. Innovations in preparatory procedures of the bladder of rat fetuses have been developed which make possible detailed scanning and transmission electron microscopic and light microscopic examination of cloaca and …


Insites, Fall 1986, Utah State University Oct 1986

Insites, Fall 1986, Utah State University

inSites

Magazine of the Department of Landscape Architecture and Environmental Planning


The Interface Of Cells And Their Matrices In Mineralized Tissues: A Review, S. J. Jones, A. Boyde, N. N. Ali Oct 1986

The Interface Of Cells And Their Matrices In Mineralized Tissues: A Review, S. J. Jones, A. Boyde, N. N. Ali

Scanning Electron Microscopy

The interface between cells and matrices in mineralized tissues formed in vivo has been studied mainly by looking at the matrix surface, which is easily prepared, and not at the cell surface, which presents problems. Vertebrate calcified tissues range from being acellular to highly cellular, but for all the tissues the formative cells lay down and organise a cell-specific matrix, although this may be deposited initially on a different tissue-type. The formation of hard tissues is a group activity of many cells; resorption is the province of one cell, though it may be controlled by others in the vicinity.

Cell-matrix …


Scanning Electron Microscopy In Bone Pathology: Review Of Methods, Potential And Applications, A. Boyde, E. Maconnachie, S. A. Reid, G. Delling, G. R. Mundy Oct 1986

Scanning Electron Microscopy In Bone Pathology: Review Of Methods, Potential And Applications, A. Boyde, E. Maconnachie, S. A. Reid, G. Delling, G. R. Mundy

Scanning Electron Microscopy

This article reviews the applications of SEM methods to human bone pathologies referring to studies made at UCL. We consider the methods which may be most suitable; these prove to be not "routine" in the context of most bio-medical applications of SEM.

Valuable information can be obtained from a bone sample if its edges are ground flat, before making either (a) a matrix surface preparation by washing away all the cells or (b) a mineralising front preparation, by also dissolving the osteoid -for which hydrogen peroxide is recommended to produce a robust specimen. BSE contrast from a cut block surface …


Utah Science Vol. 47 No. 3, Fall 1986 Oct 1986

Utah Science Vol. 47 No. 3, Fall 1986

Utah Science

70 CHROMOSOMES AND INFERTILITY IN DAIRY CATTLE T. D. Bunch, A. Maciulis and S. L. Henderson The analysis of chromosomes is providing valuable information about genetic abnormalities in cattle.

78 THE APPLICATION OF BEHAVIORAL CONCEPTS TO LIVESTOCK MANAGEMENT D. F. Balph and M. H. Balph Several principles useful in the study of human behavior may also explain livestock behavior.

86 GENETIC PROBLEMS IN MINK CULTURE L. C. Ellis and N. C. Pace Mink are an ideal animal to study genetic problems in other animals and humans.

94 UNDERSTANDING THE APPLE MAGGOT D. W. Davis and V. P. Jones Findings are …


Hormonal Regulation Of Capillary Fenestrae In The Rat Adrenal Cortex: Quantitative Studies Using Objective Lens Staging Scanning Electron Microscopy, R. P. Apkarian, J. C. Curtis Sep 1986

Hormonal Regulation Of Capillary Fenestrae In The Rat Adrenal Cortex: Quantitative Studies Using Objective Lens Staging Scanning Electron Microscopy, R. P. Apkarian, J. C. Curtis

Scanning Electron Microscopy

High magnification studies of the fenestrated capillary endothelium in the zona fasciculata (ZF) of rat adrenal glands were performed using the objective lens stage of an analytical scanning electron microscope (SEM) equipped with a lanthanum hexaboride emitter (LaB6). Resolution of surface substructure of the luminal membrane obtained with specimens decorated with gold/palladium (Au/Pd) was compared with that observed in others sputter coated with tantalum (Ta). High magnification (50,000x) of the fenestrated endothelium demonstrates that tantalum coating of the cryofractured adrenals improves the substructural detail compared to that seen in Au/Pd decorated specimens.

The procedures used in specimen preparation, …


Development Of The Otolith In Embryonic Fishes With Special Reference To The Toadfish, Opsanus Tau, Bernd H. A. Sokolowski Sep 1986

Development Of The Otolith In Embryonic Fishes With Special Reference To The Toadfish, Opsanus Tau, Bernd H. A. Sokolowski

Scanning Electron Microscopy

The development of the saccular otolith and the otolithic membrane was studied in the toadfish (Opsanus tau) using scanning and transmission electron microscopy. Development of the saccular otolith and its otolithic membrane in Opsanus begins with the formation of the primordia in embryos of 17-20 somite age. Calcification of the primordia begins shortly afterwards, although increased calcium layering and formation of the otolithic membrane corresponds to the development of a group of cells lying peripheral to the developing sensory epithelium. These cells contain an abundance of rough endoplasmic reticulum.


The Role Of Marrow Architecture And Stromal Cells In The Recovery Process Of Aplastic Marrow Of Lethally Irradiated Rats Parabiosed With Healthy Litter Mates, Keiki Hayashi, Koichi Kagawa, Michiyasu Awai, Shozo Irino Sep 1986

The Role Of Marrow Architecture And Stromal Cells In The Recovery Process Of Aplastic Marrow Of Lethally Irradiated Rats Parabiosed With Healthy Litter Mates, Keiki Hayashi, Koichi Kagawa, Michiyasu Awai, Shozo Irino

Scanning Electron Microscopy

Bone marrow aplasia was induced in rats by whole body lethal irradiation (1,000 rads by x-ray), and rats died of irradiation injury within 7 days.

Correlative studies at light (LM), transmission (TEM) and scanning electron microscopy (SEM) demonstrated swelling of endothelial and reticular cells and hemorrhage due to detachment of sinus endothelial cells on days 1 and 2. With time, structural recovery occurred without hemopoietic recovery. Reticular cells developed small intracytoplasmic lipid droplets on days 3 and 4. This resulted in fatty a plastic marrow within 7 days. On the other hand, in the marrow of irradiated rats parabiosed with …


Freeze-Dried Embedded Specimens For Biological Microanalysis, L. Edelmann Sep 1986

Freeze-Dried Embedded Specimens For Biological Microanalysis, L. Edelmann

Scanning Electron Microscopy

The main problems associated with freeze-drying of biological material for electron microscopy concern the freeze-drying temperatures and times necessary to minimize artifacts. Due to the many parameters involved these problems have to be resolved experimentally. It can be shown that good morphological preservation of chemically unfixed material is possible when freeze-drying is done exclusively in a temperature range between -80°C and -50°C. OsO4 vapour fixation of the freeze-dried tissue is not necessary and should be avoided because it may cause ion redistribution artifacts. Embedding at low temperature of properly freeze-dried material does not seem to disturb structure and ion …


Dissection Technique For Cochleas Prepared For Scanning Electron Microscopy, Sven Rydmarker, D. E. Dunn, P. Nilsson, C. Lindqvist Sep 1986

Dissection Technique For Cochleas Prepared For Scanning Electron Microscopy, Sven Rydmarker, D. E. Dunn, P. Nilsson, C. Lindqvist

Scanning Electron Microscopy

Scanning electron microscopy (SEM) permits a three-dimensional study of the surface morphology of the organ of Corti that is very useful in evaluating the condition of the apical end of the hair cells and the stereocilia. However, some laboratories have experienced problems with curling of the basilar membrane during critical point drying of cochlear specimens prepared For SEM evaluation using the Murakami or osmium thiocarbohydrazide-procedures. This curling of the basilar membrane can obstruct the view of the reticular lamina and the ciliary ends of the hair cells.

We have used a dissection method, referred to as the anchor technique, to …


Experimental Investigation Of The Genesis Of Struvite Stones In Cats, G. Sanders, A. Hesse, D. B. Leusmann Sep 1986

Experimental Investigation Of The Genesis Of Struvite Stones In Cats, G. Sanders, A. Hesse, D. B. Leusmann

Scanning Electron Microscopy

Infrared spectroscopy of feline urinary stones revealed that struvite was the main constituent in 77.6 % of all concrements. However, only in 30.8% (16/52) of struvite stone patients were any infections of the urinary tract detected.

Scanning electron microscopical comparison of non-infected feline struvite stones and human struvite concrements which had grown in the presence of infection revealed clear differences. All the feline struvite concrements were of coarse crystalline construction with the crystalline form typical of struvite. Traces of partial solution and stratification were frequently detected on the crystalline surfaces. The human struvite stones whose growth had been accompanied by …


Analysis Of Canine Urinary Stones Using Infrared Spectroscopy And Scanning Electron Microscopy, A. Hesse, G. Sanders, D. B. Leusmann Sep 1986

Analysis Of Canine Urinary Stones Using Infrared Spectroscopy And Scanning Electron Microscopy, A. Hesse, G. Sanders, D. B. Leusmann

Scanning Electron Microscopy

Infrared spectroscopic analysis of 741 canine urinary calculi revealed that struvite stones, 58% of the total, were the ones most commonly to be found. Cystine stone disease, 21%, is also of great significance for dogs, whereas calcium oxalate, urate and brushite calculi occur only seldom. 3 cases of xanthine stone formation were also noted.

SEM examination revealed structures similar to human stones such as bipyramidal weddelIite, pseudomorphs from whewellite to weddellite, apatite deposits in cystine stones and characteristic mono-ammonium-urate needles. Other, unknown, structures were also discovered such as closely-knit intergrowths of cystine and brushite strata, mono-Na-urate and mono-K-urate intergrowths and …


Visualization Of Cytoskeletal Elements And Associated Retroviral Antigens By Immunogold Transmission Electron Microscopy Of Detergent Extracted Cells, E. J. Basgall, M. M. Soong, W. A. F. Tompkins Sep 1986

Visualization Of Cytoskeletal Elements And Associated Retroviral Antigens By Immunogold Transmission Electron Microscopy Of Detergent Extracted Cells, E. J. Basgall, M. M. Soong, W. A. F. Tompkins

Scanning Electron Microscopy

Several investigators have reported an association between the cytoskeleton and viral antigens. In our laboratory, biochemical immunofluorescence and immuno-gold electron microscopy studies were conducted on TX-100 extracted NIH/3T3 cells infected with Moloney-murine leukemia virus. Cytochalasin B treatment causes reversible microfilament disruption and a concomitant decrease in virus production. No effect on microtubules was seen. Immuno-gold electron microscopy reveals an association between cytoskeletal action and the viral antigens gp70 and p15E. The results of these immunocytological and biochemical studies indicate that the cytoskeleton may play an integral role in transport and processing of viral gene-envelope products.


The Microvascular Architecture Of The Vestibule And The Endolymphatic Duct And Sac Of The Rat In Vascular Corrosion Casts, Takuya Ohmichi, Ryuske Saito, Kiyoshi Matsubara, Kazutaka Terazawa, Shuji Tasaka, Yoshio Ogura Sep 1986

The Microvascular Architecture Of The Vestibule And The Endolymphatic Duct And Sac Of The Rat In Vascular Corrosion Casts, Takuya Ohmichi, Ryuske Saito, Kiyoshi Matsubara, Kazutaka Terazawa, Shuji Tasaka, Yoshio Ogura

Scanning Electron Microscopy

The blood vessels of the vestibule and the endolymphatic duct and sac (ES) of the rat were reproduced with methacrylate casting medium and observed under a scanning electron microscope.

Dense capillary networks of the macula utriculi and the macula sacculi were observed. The collecting venules from the vestibule emptied into the vein of the vestibular aqueduct (VVAQ). The plexus of the vessels in the ES was triangular in shape and had anastomoses with vessels of the bone and dura and drained into the VVAQ. The posterior meningeal artery (PMA) gave off two branches to the ES. These findings supported the …


Statolith Formation In Cnidaria: Effects Of Cadmium On Aurelia Statoliths, D. B. Spangenberg Sep 1986

Statolith Formation In Cnidaria: Effects Of Cadmium On Aurelia Statoliths, D. B. Spangenberg

Scanning Electron Microscopy

Statolith formation in Cnidaria was reviewed with an emphasis on Aurelia statoliths. The review provides information on the chemical composition, mechanisms of initiation of mineralization, and effects of environmental factors on Cnidarian statolith formation. Environmental factors discussed include modified sea water ingredients, X-irradiation, clinostat rotation, and petroleum oil ingredients. A detailed account of the effects of cadmium on mineralization and demineralization of Aurelia statoliths is given. Cadmium at dosages of 2 to 4 μM significantly reduces statolith numbers in developing ephyrae. At a dosage of 3 μM, cadmium accelerates statolith loss in unfed ephyrae studied at 4 and 8 days …


Otoconia As Test Masses In Biological Accelerometers: What Can We Learn About Their Formation From Evolutionary Studies And From Work In Microgravity?, Muriel D. Ross, Kathleen M. Donovan Sep 1986

Otoconia As Test Masses In Biological Accelerometers: What Can We Learn About Their Formation From Evolutionary Studies And From Work In Microgravity?, Muriel D. Ross, Kathleen M. Donovan

Scanning Electron Microscopy

This paper reviews previous findings and introduces new material about otolith end organs that help us to understand their functioning and development. In particular, we consider the end organs as biological accelerometers. The otoconia are dealt with as test masses whose substructure and evolutionary trend toward calcite may prove significant in understanding formation requirements. Space-flight helps illuminate the influence of gravity, while right-left asymmetry is suggested by study of certain rat strains.


Solder Characterization On Ancient Gold Artifacts With The Electron Microprobe, A. R. Duval, C. Eluere Sep 1986

Solder Characterization On Ancient Gold Artifacts With The Electron Microprobe, A. R. Duval, C. Eluere

Scanning Electron Microscopy

The Laboratoire de Recherche des Musees de France has tested the applicability of the scanning electron microscope with X-ray analysis facilities in the study of ancient gold artifacts and particularly the joining processes. Three types of joining methods are known to have been used in Ancient Times : sintering, brazing with Au-Ag-Cu alloys and copper-salt binding. X-ray distribution maps of selected elements on very small areas show clearly the different processes used in the manufacture of Oriental and Iron-Age artifacts.


The Capillary Bed In The Choroid Plexus Of The Lateral Ventricles: A Study Of Luminal Casts, Enrico D. F. Motti, Hans-Georg Imhof, Robert C. Janzer, Klaus Marquardt, Gazi M. Yasargil Sep 1986

The Capillary Bed In The Choroid Plexus Of The Lateral Ventricles: A Study Of Luminal Casts, Enrico D. F. Motti, Hans-Georg Imhof, Robert C. Janzer, Klaus Marquardt, Gazi M. Yasargil

Scanning Electron Microscopy

Micro-angioarchitecture of the choroid plexus of the lateral ventricles is investigated in microcorrosion casts of animal and human preparations studied with the scanning electron microscope. The capillary bed in the diverse regions of the tissue belongs to one of three patterns: (1)-a network of capillary meshes that envelop the larger arteries and veins predominates in the central segment. (2)-in the villous regions a "leaf-like" organization of sinusoids is found together with (3)-fronds of "glomerular" formations. "Glomeruli" are formed when arterial afferents and venous efferents converge in a quasi hilar structure before branching in arterio-venous loops. Nodular thickenings are observed on …