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The Role Of Scanning Electron Microscopy In Periodontal Research, A. Carrassi, S. Abati, G. Santarelli

Scanning Microscopy

During recent years a great amount of research has led to a better understanding of the etiology, pathogenesis and pattern of progression of periodontal diseases. Scanning electron microscopy (SEM) has contributed to this improvement, mainly with respect to histology of periodontal tissues, the description of the morphology and distribution of bacteria on the exposed root surface, analysis of the host-parasite interactions on the gingival pocket wall, and morphological evaluation of root treatment. This review deals with all these topics. Unusual types of SEM research are also described and discussed. Uncommon sample preparation techniques for SEM in periodontal research are described. …

The Cell Water Problem Posed By Electron Microscopic Studies Of Ion Binding In Muscle, L. Edelmann

Scanning Microscopy

The question whether cell K⁺ is free or bound in the striated frog muscle has been investigated during the last 10 years by different cryomethods and electron microscopy. The results support the view that most of cellular ions are osmotically inactive and that therefore the observed cell water activity must be explained by a model which assumes a specific cell water structure. According to the association-induction hypothesis, cell water is influenced by macromolecules and has low solubilities for Na⁺ and other solutes which therefore are partly excluded from cellular water. Autoradiography of frozen hydrated Na⁺ loaded muscles …

Microvascular Casting Of The Lung: Vascular Lavage, Dean E. Schraufnagel, Aloisia Schmid

Scanning Microscopy

Corrosion casting is an important tool for the study of microvascular structure, but unlike tissue preparation for light and electron microscopy, few controlled studies of the methods for preparation of microvascular casts for scanning electron microscopy have been reported. Most vascular casting begins with rinsing cells from the lumen of the blood vessels, but the necessity of this has not been shown. Because of a report of successful casting without rinsing and light microscopic evidence of edema with complete rinsing prior to casting, this preparation procedure was examined. Casts of lung vasculature that were thoroughly rinsed were compared to those …

A Review Of Methodology And Quantification In Dental Microwear Analysis, K. D. Gordon

Scanning Microscopy

Dental microwear analysis is a method of inferring oral events (primarily food processing and aspects of masticatory biomechanics) from microscopic abrasion patterns retained on the enamel surfaces of teeth. Although some qualitative pattern differences may be easily distinguishable, most of the significant results produced thus far have derived from quantified studies of SEM images of occlusal enamel. It often goes unnoticed by readers of microwear reports who are not themselves specialists that microwear analysis is essentially a statistical method, not a visual one. In this review of current techniques and methods, several problems in current approaches are detailed. It is …

A Review Of Dental Microwear And Diet In Modern Mammals, Mark F. Teaford

Scanning Microscopy

Recent work has shown that microscopic wear patterns on teeth may yield insights into variations in diet and tooth use in modern and prehistoric mammals. This paper presents a review of dental microwear and diet in modern mammals, plus a discussion of topics for further research. To date, incisor and molar microwear have been examined, although there are far fewer studies of the former. Facilitated by the use of high-resolution casts and scanning electron microscopy, analyses have ranged from: qualitative to quantitative, low magnification to high magnification, and experimental studies to comparative studies of museum collections. Results are encouraging and …

Preparation Of Biological Samples For Transmission X-Ray Microanalysis: A Review Of Alternative Procedures To The Use Of Sectioned Material, D. C. Sigee

Scanning Microscopy

Although transmission X-ray microanalysis of biological material has traditionally been carried out mainly on sectioned preparations, a number of alternative procedures exist. These are considered under three major headings - whole cell preparations, analysis of cell homogenates and biological fluids, and applications of the technique to microsamples of purified biochemicals. These three aspects provide a continuous range of investigative level - from the cellular to the molecular.

The use of X-ray microanalysis with whole cell preparations is considered in reference to eukaryote (animal) cells and prokaryotes - where it has particular potential in environmental studies on bacteria. In the case …

Quantitative Morphology Of Synaptic Plasticity In The Aging Brain, Carlo Bertoni-Freddari, William Meier-Ruge, Jurg Ulrich

Scanning Microscopy

Quantitation of synaptic ultrastructural changes is of great importance in neurobiology, since merely qualitative alterations, if not extreme, are not readily detectable. In the present paper we discuss our previous and present findings on the number (numerical density: Nv), size (average length of the synaptic profiles: L) and surface contact area (surface density: Sv) of the synaptic junctions in aging rodent and human brains. We found that number and size of the synapses are in a close inverse relationship so as to maintain the total surface contact area among the nerve cells constant. These three parameters are closely related to …

Microcorrosion Casting In Normal And Pathological Biliary Tree Morphology, E. Gaudio, L. Pannarale, F. Carpino, G. Marinozzi

Scanning Microscopy

The organization of the intrahepatic biliary tree was studied in three dimensions by scanning electron microscopic (SEM) corrosion casts, in normal and cholestatic rat liver.

In the normal liver the observation revealed the features of the biliary passages from the bile canaliculi to the canaliculo-ductular junction, to the ductules and the bile ducts, confirming previous SEM observations.

In cholestatic liver, the modifications and the proliferation of bile ductules appear clearly.

Resin flow from canalicular to sinusoidal network was never observed.

The method was found to be very useful in the evaluation of the architecture of the intrahepatic biliary tree, under …

Extraneous Background-Correction Program For Matrix Bound Multiple Point X-Ray Microanalysis, W. C. De Bruijn, M. P. C. Van Miert

Scanning Microscopy

A program is described that allows online determination of extraneous background in multiple point X-ray microanalytical matrices. The program is based upon the calculations of the extraneous background for the film (when present), the standard and the unknown by (100 sec.) point analysis. The program searches for a peak-free part of the spectrum in which the calculated value for the extraneous background is about equal to the value in this region of the spectrum (=b_e). Online the contents of this b_e-region is subtracted from an unmanipulated continuum region in the vicinity of the element present in …

Contrasting Views On The Organization Of Cytoplasm, J. S. Clegg

Scanning Microscopy

The widely held conception of cytoplasm as a concentrated solution of dissolved proteins and other macromolecules, metabolites and inorganic ions, within which the various organelles and other formed elements are suspended appears to be a gross over-simplification. Evidence to be reviewed briefly here, from a wide variety of experiments and cell types, indicates that a much more extensive organization exists, in animal cell cytoplasm at least. Results from experiments on dextran sulfate permeabilized L-929 cells will be presented which support that organized paradigm. It seems likely that this intracellular architecture also exerts a strong influence on the water in the …

Presence Of Calcium Oxalate Crystals In The Mammalian Thyroid Gland, Raymond L. Hackett, Saeed R. Khan

Scanning Microscopy

Birefringent crystals of calcium oxalate have been previously identified in the colloid of human thyroid glands. We found such crystals in 19/20 adult thyroids at autopsy, in 4/ 20 infants at autopsy, and, using frozen sections, in 19/20 thyroids partially or totally removed at surgery. These crystals were soluble in hydrochloric acid, insoluble in acetic acid, and contained only calcium by energy dispersive X-ray microanalysis, confirming their calcium oxalate character. Similar crystals were found in equine and ovine thyroids.

Arterial Elastin As Seen With Scanning Electron Microscopy: A Review, Margot R. Roach, S. H. Song

Scanning Microscopy

All large arteries contain elastin, collagen, and muscle which can be seen with light microscopy and transmission electron microscopy. Elastin forms an internal elastic lamina (IEL) in all arteries, but also forms multiple fenestrated sheets in the media of the aorta and other large arteries. The fenestrations in the media are larger than those in the IEL. The adventitial elastin is more fibrous and often contains tubular elastin surrounding vasa vasorum when prepared by removing all non-elastin by placing the aorta in 0.1 N NaOH at 70-75°C for five hours. The fenestrations are larger near branches and in an experimentally …

The Effect Of Fatigue On Essential Element Distribution In The Rabbit Masseter, M. B. Engel, J. K. Bressman

Scanning Microscopy

The rabbit masseter is composed of mainly fast fatiguable type IIB fibers which give a positive mATPase reaction at pH 9.3. To study the effect of fatigue on the distribution of some crucial elements, the masseter was stimulated electrically for 45 minutes. The contralateral muscle served as a control. Control and experimental tissues were rapidly excised, and frozen in isopentane cooled to -150°C in liquid nitrogen. Sections were cut in a cryostat and prepared by freeze-drying. Water content of fatigued muscle was significantly higher than controls: 79.3% versus 77.3%. The fatigued state was verified by glycogen depletion viewed in PAS-stained …

Ultrastructure And Histochemistry Of The Vas Deferens Of The Salamander Rhyacotriton Olympicus: Adaptations For Sperm Storage, Edward J. Zalisko, John H. Larsen Jr.

Scanning Microscopy

The vas deferens of the salamander Rhyacotriton olmpicus is composed of (1) a peritoneal epithelium, (2) connective tissue wiith fibroblasts, melanophores, circular smooth muscle, capillaries, and unmyelinated nerves within a collagenous matrix, and (3) an inner layer of cuboidal epithelium partially covered by ciliated squamous cells at the lumen. The lumen and apical cytoplasm of both epithelial cell types contain strongly PAS-positive granules. The cuboidal cells contained numerous swollen rough endoplasmic reticulum cisternae, mitochondria, and apical dense granules suggesting a high degree of secretory activity possibly involved in sperm maintenance. Fewer mitochondria, rough endoplasmic reticula, and granules in squamous cells …

New Uses Of Livestock Guarding Dogs To Reduce Agriculture/Wildlife Conflicts, R. Coppinger, J. Lorenz, Lorna Coppinger

Wildlife Damage Management Conference

Pilot programs in several states have shown that livestock guarding dogs are 70-80% effective in reducing predation on livestock by wildlife, primarily coyotes. In order to increase that percentage, ineffective dogs were studied and new techniques tested that had the potential of turning problems into successes.

From the population of over 1,000 dogs that has been placed on farms and ranches nationwide during the past ten years under the auspices of the Livestock Dog Project at Hampshire College, data was analyzed for each of the three basic behaviors (trustworthy, attentive, protective) that a good guardian needs to exhibit. A wide …

Categorization And Seasonal Periodicity Of Terrestrial Vertebrate Pest Control Inquiries In Virginia, Harry J. Dutton, Jefferson L. Waldon, Peter T. Bromley

Wildlife Damage Management Conference

Information requests for species-specific preventive and control measures directed to the state's extension wildlife specialist were recorded by species or species group, month, day, and year, and by type of human group inquiring. Skunks (15.5%), snakes (14.7%), and bats (10.9%) were inquired about most often. Homeowners (67.4%) were the most frequent inquirers. Summer (43.5%) and spring (29.0%) were the seasons when most information requests occurred. Woodpeckers (16.0%) were the most frequently reported species in the spring. In the summer, the most frequently requested information was about bats (20.2%). Snakes (29.7%) were the most frequently reported species in the fall. Over …

Catch Effectiveness And Selectivity Of Several Traps, Edward P. Hill

Wildlife Damage Management Conference

The effectiveness and selectivity of several traps and trap modifica­tions were field-evaluated and compared in Alabama from 1977 to 1980. No. 220 Conibear traps placed in baited open-end boxes (TB) on the ground posed a hazard to dogs and were not recommended for general use in terrestrial sets. They may be effective to control feral dogs in special situations or areas. TB devices attached to tree trunks 1 m above the ground eliminated the hazard to dogs, but rendered the trap ineffective for taking small mammals.

No. 220 Conibear traps with selective position treadle triggers placed in trail water-sets were …

Wildlife Damage To Agriculture In Nebraska: A Preliminary Cost Assessment, R. J. Johnson, R. M. Timm

Wildlife Damage Management Conference

We estimate the annual financial losses resulting from wildlife damage to major crops and livestock in Nebraska. For each wildlife species, the damage problem is presented along with a description of how the estimate was made. Field crop estimates include losses from Plains pocket gophers (Geomys bursarius), commensal rodents (Rattus norvegicus and Mus musculus), field rodents in grain fields (e.g. Peromyscus maniculatus, Dipodomys ordi, Spermophilus tridecemlineatus), house sparrows (Passer domesticus), blackbirds (e.g. Agelaius phoeniceus and Ouiscalus guiscula), lagomorphs (Sylvilagus floridanus, Lepus californicus, and L. townsendii), deer (Odocoileus …

Wolf, Golden Eagle, And Coyote Problems In Montana, B. W. O'Gara, W. Rightmire

Wildlife Damage Management Conference

The average annual reported loss of sheep and lambs to predators in Montana from 1982 through 1986 was 46,000 animals worth $1,980,000. During recent years, coyote predation has been the single most important cause of death for lambs. Coyotes accounted for 80% of the predator kills during 1985 and 72% during 1986, and 8,321 coyotes were killed by ADC during those 2 years. Aerial gunning accounted for more than half of the kills. During the first year of a study on a ranch in western Montana without predator control, coyotes killed 8% of the ewes and 27% of lambs. Predation …

Deer Damage Control Preferences And Use Decisions Of New York Orchardists, K. G. Purdy, W. F. Siemer, G. A. Pomerantz, T. L. Brown

Wildlife Damage Management Conference

Previous studies in New York, the nation's second leading state in apple production, have contributed much to deer management decisions that give consideration to orchardists' concerns about crop damage. Little information, however, has been reported about orchardists' reasons for adopting or not adopting particular types of deer damage controls or their preference for various forms of possible damage control assistance. Two complementary studies, conducted in early 1987 by the Human Dimensions Research Unit, Department of Natural Resources, Cornell University, have addressed these information needs. A mail survey of orchardists in an important fruit-producing region of southeastern New York indicated that …

The Urban-Suburban Canada Goose: An Example Of Short-Sighted Management?, Michael R. Conover

Wildlife Damage Management Conference

During the last 30 years, Canada Goose (Branta canadensis) populations have become established in many urban and suburban parts of North America. Most of these scattered populations were established when live geese were released in these areas or nearby rural areas by individual hunters, sportmen's groups and game agencies. The birds quickly found lawns in urban-suburban areas an abundant source of nutritious grass for grazing and discovered people willing to provide supplementary handouts. The resident goose populations thrived; in Connecticut alone their population has increased to 9,000. However, the increased populations contributed little to the hunter's take because …

Management Of Suburban Deer: An Emerging Controversy, Daniel J. Decker

Wildlife Damage Management Conference

During the last 10 years the presence of deer (Odocoileus virginianus) in suburban areas has become an increasing concern from the standpoint of damage and nuisance problems. It is unclear whether (a) overall deer numbers in suburban environments have increased (possibly because of residential development in "natural" settings and creation of food sources represented by residents' ornamental plantings and vegetable gardens), (b) more development in suburban areas has forced deer into adjacent remaining patches of suitable habitat, resulting in increased deer densities in certain localities, or (c) some combination of both. Regardless of the factors perpetrating the situation, …

The Bird Strike Hazard (Bash) Program, Edgardo R. Farraro, Russell P. Defusco

Wildlife Damage Management Conference

The hazards birds pose to aircraft has been of concern to the Air Force for more than 20 years. After losing several aircraft due to bird strikes in the early 1960's, the Air Force formed a team to evaluate bird hazards to Air Force aircraft. The team, from the Air Force Weapons Laboratory (AFWL) at Kirtland AFB NM, handed over this mission to the Bird Aircraft Strike Hazard (BASH) Team at HQ Air Force Engineering and Services Center (AFESC) at Tyndall AFB in 1975. In 1986 (October) the BASH team moved to Bolling AFB, Washington DC.

Urban Gray Squirrel Damage And Population Management: A Case History, J. Hadidian, D. Manski, V. Flyger, C. Cox, G. Hodge

Wildlife Damage Management Conference

Lafayette Park, a 3.0 hectare national park located across the street from the White House in Washington D.C., has had a gray squirrel (Sciurus carolinensis) density as high as 50 animals/hectare. In recent years this large population caused significant damage to mature trees and other vegetation. In keeping with the legislative mandate to protect and preserve the historic landscape in Lafayette Park, the National Park Service implemented a squirrel management program following an Integrated Pest Management (IPM) approach. The population was studied and monitored to determine the ecological bases for high squirrel numbers. Action was taken through a …

Controlling Blackbirds And Starlings At Winter Roosts Using Pa-14, J. F. Heisterberg, A. R. Stickley Jr., K. M. Garner, P. D. Foster Jr.

Wildlife Damage Management Conference

The only EPA-registered chemical for lethal control of winter roosting blackbird (Icterinae) and European starling (Sturnus vulgaris) populations is Compound PA-14 Avian Lethal Agent (PA-14). Between 1978 and 1987, 39 PA-14 spray operations, 15 by helicopter and 24 by ground-based spray systems, have been conducted at 33 winter roosts in Kentucky, Tennessee, and Alabama. In-roost bird mortality for the aerial operations have been poor, averaging only 4% of the pretreatment roost populations or 114,000 birds killed per spray operation. Although very labor-intensive, a ground-based sprinkler system application method has proven much more successful, averaging 67% in-roost bird mortality …

Coyote Control Techniques And Their Applications In The Eastern United States, Rick D. Owens

Wildlife Damage Management Conference

Conflicts between coyotes and man's activities are varied and include such problems as predation on livestock, agricultural crops, and other wildlife, as well as threats to human health or safety. Formerly restricted to the Great Plains, the coyote's adaptability has enabled expansion of its population throughout most of the United States, Canada and Mexico. This expansion has occurred in spite of large-scale control and/or eradication efforts.

Landowner Perceptions Of Beaver Damage And Control In Arkansas, T. B. Wigley, M. E. Garner

Wildlife Damage Management Conference

Landowner perceptions of damage caused by beavers (Castor canadensis) and of beaver control programs in Arkansas were determined by mail survey. Beavers were present on lands owned by 36% of the 1,716 respondents. Girdled timber, blocked culverts and flooded timber were the first, second and third most common damages reported, respectively. Thirty-two percent of all respondents and 90% of those with beavers reported at least one form of damage. Four percent of land owned by respondents was flooded by beavers. Of landowners with beavers, 50% described damage as substantial or severe, and 46% perceived damage as unreasonable. At …

Involving Hunting And Trapping In Cooperative Wildlife Damage Control, Ed Hackett

Wildlife Damage Management Conference

The perception of a wildlife damage problem may vary greatly among groups with a stake in the problem. To the deer hunter, there is no such problem as too many deer. To the farmer, in the midst of a personal economic disaster, one deer may seem too many. To the conservation officer (CO) who has spent a career building deer populations, the farmer's problem may be a sign of success. To the USDA-APHIS-ADC staff member, solving the farmer's problem may be the most important issue. The key to resolving these conflicting views of the same event is to make each …

Bait Stations For Controlling Voles In Apple Orchards, Mark E. Tobin, Milo E. Richmond

Wildlife Damage Management Conference

Bait stations made with polyvinylchloride (PVC) pipe were compared with hand-broadcast applications of rodenticides for achieving long-term control of pine and meadow vole populations (Microtus pinetorum and M. pennsylvanicus, respectively) in two apple orchards in the mid-Hudson Valley of New York. The stations were constructed of three pieces of 1.5-in diameter PVC tubing joined together in the shape of an inverted "T". Roofing shingles were placed over the entrances to some of the bait stations to encourage use by voles, while others were left uncovered. All stations were tied to trees, with no attempt to place them near …

An Evaluation Of Controlled Hunting For Management Of Feral Pigeons, Michael D. Hoy, Albert E. Bivings

Wildlife Damage Management Conference

Pigeons (Columba livia) are a problem for municipal governments throughout most of the eastern United States. Toxicants, sterilants, trapping, and shooting are the principal control techniques. Due to a general public aversion to toxicants and to monetary constraints, a pigeon control program which utilized periodic hunting pressure was initiated in Stuttgart, Arkansas County, Arkansas. Guidelines for organization of controlled hunts are presented along with pigeon harvest rates and population trends. The city government and interested citizens consider the program to be successful and cost effective.