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Zinc Deficiency Produces Time-Related Ultrastructural Changes In Rat Cheek Epithelium, Shahid H. Ashrafi, Nasser A. H. Said-Al-Naief Nov 1995

Zinc Deficiency Produces Time-Related Ultrastructural Changes In Rat Cheek Epithelium, Shahid H. Ashrafi, Nasser A. H. Said-Al-Naief

Scanning Microscopy

The subject of this study was whether the ultrastructural changes in cheek epithelium of zinc-deficient rats are time related. Weanling male Sprague Dawley rats were fed a zinc-deficient diet containing 0.4 ppm zinc (ZD) ad libitum and controls were pair-fed zinc adequate diet containing 40 ppm zinc. After 9, 18, and 27 days of zinc deficiency, specimens from cheek epithelium of both groups were processed for transmission electron microscopy. Partial conversion of the orthokeratinized cheek epithelium to parakeratinized was seen as early 9 days. An electron-lucent band surrounding the nucleus was observed in ZD cells. Mitochondria, tonofilaments, keratohyalin granules and …

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Immunogold Labeling For The Diagnosis Of Leukemia By Transmission And Scanning Electron Microscopy, Etienne De Harven, Davide Soligo, Hilary Christensen Nov 1995

Immunogold Labeling For The Diagnosis Of Leukemia By Transmission And Scanning Electron Microscopy, Etienne De Harven, Davide Soligo, Hilary Christensen

Scanning Microscopy

For the cell type diagnosis of leukemia in adult patients, particularly when the sampling of bone marrow is difficult, the study of peripheral blood leukocytes (PBLs) by immuno-electron microscopy provides significant information, as illustrated here in two cases of hairy cell leukemia and seven cases tentatively identified as megakaryoblastic leukemia (M7). Indirect immunogold labeling with the B-ly7 monoclonal antibody (CD103) proved valuable in confirming the diagnosis of hairy cell leukemia. Immunogold labeling for the GplIIa platelet glycoprotein (CD61) was used in cases where the light microscopy of blood films revealed possible megakaryoblastic leukemia. Under the electron microscope, however, the CD61 …

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Alterations In Intestinal Transport Of Oxalate In Disease States, Marguerite Hatch, Robert W. Freel Nov 1995

Alterations In Intestinal Transport Of Oxalate In Disease States, Marguerite Hatch, Robert W. Freel

Scanning Microscopy

Normally, absorption of oxalate from dietary sources can occur in all segments of the intestinal tract. However, alterations in both the magnitude and direction of oxalate fluxes across the intestine can occur in disease states. In enteric hyperoxaluria, enhanced absorption of oxalate by the large intestine is caused by increased permeability of a shunt conductance induced by malabsorbed bile salts and fatty acids. In this condition, the contribution of a paracellular passive flux of oxalate moving along its electrochemical gradient will predominate when intraluminal concentrations of free oxalate are high. In contrast, in chronic renal failure, secretion of oxalate can …

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Zeta Potential Measurement And Particle Size Analysis For A Better Understanding Of Urinary Inhibitors Of Calcium Oxalate Crystallization, L. C. Cao, G. Deng, E. R. Boeve, W. C. De Bruijn, R. De Water, C. F. Verkoelen, J. C. Romijn, F. H. Schroder Nov 1995

Zeta Potential Measurement And Particle Size Analysis For A Better Understanding Of Urinary Inhibitors Of Calcium Oxalate Crystallization, L. C. Cao, G. Deng, E. R. Boeve, W. C. De Bruijn, R. De Water, C. F. Verkoelen, J. C. Romijn, F. H. Schroder

Scanning Microscopy

To better understand urinary inhibitors of calcium oxalate crystallization, both zeta potential measurement and particle size analysis were chosen to illustrate: (1) the potential therapeutic efficacy of G872, a semi-synthetic sulfated polysaccharide, in stone prevention; and (2) the relative contribution of various urinary fractions {e.g., ultrafiltered urine (UFU), Tamm-Horsfall protein (THP), urinary polyanionsprecipitated with cetylpyridinium chloride (CPC), urinary macromolecular substances with different concentration ratios (UMSl0,50,90 and UMS'l0,50,90) and THP-free urine (THPFU)} to total urinary inhibitory activity. The results showed: (1) addition of G872 significantly enhances urinary inhibitory activity and negative zeta potential values; (2) re-addition of the CPC to UFU …

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The Professional Evolution Of Wildlife Damage Management, James E. Miller Nov 1995

The Professional Evolution Of Wildlife Damage Management, James E. Miller

Wildlife Damage Management Conference

The term -- wildlife damage management, in lieu of animal damage control, vertebrate pest control, or nuisance animal control -- has become the currently recognized term for an area of wildlife management that a growing number of professionals spend a significant part of their time and/or career working in. The acceptance of this terminology is, however, a part of the continuing evolution of the profession and not simply a name change for political correctness. Admittedly, my purpose is not to validate or beg acceptance of this terminology. Rather, what I hope to do is to justify the underlying premise of …

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Efficacy Of Shooting Permits For Deer Damage Abatement In Wisconsin, Rick R. Horton, Scott R. Craven Nov 1995

Efficacy Of Shooting Permits For Deer Damage Abatement In Wisconsin, Rick R. Horton, Scott R. Craven

Wildlife Damage Management Conference

The efficacy of out-of-season shooting permits for deer damage abatement in Wisconsin has not been critically evaluated. We used deer damage shooting permits to remove 21 antlerless deer (Odocoileus virginianus) from 7 heavily damaged alfalfa fields to evaluate subsequent impact on crop damage. Volunteer shooters, using permits issued to the landowners, hunted a minimum of 3 nights/week throughout the growth of the third alfalfa crop (Aug. 1 - late Sept.). We calculated the difference between the assessed damage to the second crop (untreated) and the third crop (treated) on treatment and control farms. We found no significant difference …

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Incorporating Depredation Permits Into Integrated Damage Management Plans For Aquaculture Facilities, Philip Mastrangelo, Charles Sloan, Kevin Bruce Nov 1995

Incorporating Depredation Permits Into Integrated Damage Management Plans For Aquaculture Facilities, Philip Mastrangelo, Charles Sloan, Kevin Bruce

Wildlife Damage Management Conference

Increasing bird depredation at aquaculture facilities in Alabama, Arkansas, Louisiana, and Mississippi creates economic hardships for many fish farmers. Solutions to bird depredation at these facilities require the development of integrated damage management plans that will reduce damage levels while insuring minimal impacts to bird populations. Damage management plans developed for fish farmers by the U.S. Department of Agriculture, Animal and Health Plant Inspection Service, Animal Damage Control (ADC) program always include non-lethal control recommendations. If nonlethal control is ineffective or only marginally effective in reducing damage, the management plans may also recommend the issuance of depredation permits by the …

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A Historical Perspective Of Catfish Production In The Southeast In Relation To Avian Predation, Donald F. Mott, Martin W. Brunson Nov 1995

A Historical Perspective Of Catfish Production In The Southeast In Relation To Avian Predation, Donald F. Mott, Martin W. Brunson

Wildlife Damage Management Conference

Production of aquaculture species, especially catfish (Ictalurus punctatus) in the Mississippi Delta, is a relatively new and expanding industry. Catfish production represents the largest dollar value of the aquaculture industry, accounting for approximately 50% of the entire industry. Mississippi is responsible for 82% of the total U.S. catfish production. Fish-eating bird populations have capitalized on this new food source. Double-crested cormorants (Phalacrocorax auritus), great blue herons (Ardea herodias), and great egrets (Casmerodius albus) are the primary predators on catfish. Cormorant caused losses in excess of $2 million per year have been reported in …

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Relationships Between Wild Turkeys And Raccoons In Central Mississippi, Charles D. Lovell, Darren A. Miller, George A. Hurst, Bruce D. Leopold Nov 1995

Relationships Between Wild Turkeys And Raccoons In Central Mississippi, Charles D. Lovell, Darren A. Miller, George A. Hurst, Bruce D. Leopold

Wildlife Damage Management Conference

Reduced trapping and hunting of predators has led to concerns that increased predator densities may affect game species populations. Therefore, we investigated effects of predation on the wild turkey population on Tallahala Wildlife Management Area (TWMA), Mississippi, from 1984-94. We also determined trends in raccoon trapping and hunter harvest in Mississippi. Predation of nests (eggs), nesting hens, and poults caused a population decline on TWMA. Most (88%) nest failures were caused by predation from 1984-94; raccoons were the dominant predator. Declining raccoon hunter harvest from 1980-94 was correlated with declining hunter effort. Trapping license sales and trapping harvest also declined. …

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From Deer Problem To People Solution: A Case Study From Montgomery County, Maryland, Jonathan S. Kays, Douglas Tregoning Nov 1995

From Deer Problem To People Solution: A Case Study From Montgomery County, Maryland, Jonathan S. Kays, Douglas Tregoning

Wildlife Damage Management Conference

Montgomery County, Maryland, a 495 square-mile area adjacent to Washington, D.C., is a rapidly developing, highly educated suburban community with one of the highest per capita incomes in the nation. There is increasing concern for the growth and impact of white-tailed deer (Odocoileus virginianus) populations by agricultural interests, resource professionals and residential landowners. The Montgomery County Council assembled a task force of stakeholders to examine relevant information and propose deer management options. The task force report provided detailed information on the county deer situation, 11 management alternatives, and 9 final recommendations. The county parks administrator appointed a staff …

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Apple Production, Vole Control, And Wild Turkeys: Finding A Balance In Vermont, Richard B. Chipman, Dennis Slate, Abigal J. Duke, Lorraine Berkett, Douglas Blodgett Nov 1995

Apple Production, Vole Control, And Wild Turkeys: Finding A Balance In Vermont, Richard B. Chipman, Dennis Slate, Abigal J. Duke, Lorraine Berkett, Douglas Blodgett

Wildlife Damage Management Conference

Meadow voles (Microtus pennsylvanicus) and pine voles (Microtus pinetorum) cause extensive damage to apple trees by gnawing and girdling trunk and root systems. In 1991, approximately 70% of Vermont's 90 commercial apple producers were using zinc phosphide (ZP) treated cracked corn to manage vole damage. From November 1991 through January 1992, 36 confirmed wild turkey (Meleagris gallopavo) deaths were attributed to the broadcast application of ZP treated cracked com in Vermont orchards. As a result of public concern regarding impacts to nontarget wild turkeys, a working group was formed with representation of various state …

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Ecosystem Management And Wildlife Management: Compatible Or Conflicting?, David C. Guynn Jr., Greg K. Yarrow Nov 1995

Ecosystem Management And Wildlife Management: Compatible Or Conflicting?, David C. Guynn Jr., Greg K. Yarrow

Wildlife Damage Management Conference

Examples of wildlife-human conflicts include deer-automobile collisions, disease transmission concerns, and damage to various commodities (e.g. agricultural crops, timber production). The extent of these problems is increasing at a time when American's attitudes are shifting emphasis from commodity production to concern for the environment. Ecosystem management has been proposed as a strategy to balance concerns for commodity production and the environment. Ecosystem management, unlike traditional natural resource management, will require management over large areas for long periods of time. This new philosophy of land management requires that the natural resource base be viewed in its entirety, and not as separate …

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Blackbirds And Starling Killed At Winter Roosts From Pa-14 Applications, 1974-1992: Implications For Regional Population Management, Richard A. Dolbeer, Donald F. Mott, Jerrold L. Belant Nov 1995

Blackbirds And Starling Killed At Winter Roosts From Pa-14 Applications, 1974-1992: Implications For Regional Population Management, Richard A. Dolbeer, Donald F. Mott, Jerrold L. Belant

Wildlife Damage Management Conference

The surfactant PA-14, registered with the U.S. Environmental Protection Agency (EPA) in 1973 by the federal Animal Damage Control (ADC) program, was used for 19 years (1974-1992) for lethal control of roosting blackbirds (Icterinae) and European starlings (Sturnus vulgaris) in the United States. In 1992, the ADC program withdrew the registration of PA-14 because of costs required to provide additional EPA-requested data. There were 83 roosts encompassing 178 ha treated with 33,300 L of PA-14 from 1974-1992. An estimated 38.2 million birds (48% common grackles [Ouiscalus quiscula], 30% European starlings, 13% red-winged blackbirds [ …

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Comparison Of Predation Rates On Wild Turkey Hens Between Two Forest Ecosystems In Mississippi, Michael J. Chamberlain, Darren A. Miller, Bruce D. Leopold, George A. Hurst Nov 1995

Comparison Of Predation Rates On Wild Turkey Hens Between Two Forest Ecosystems In Mississippi, Michael J. Chamberlain, Darren A. Miller, Bruce D. Leopold, George A. Hurst

Wildlife Damage Management Conference

Because of increases in predator populations, concern has arisen about effects on wild turkey (Meleagris gallopavo) populations. We examined differences in predation of adult hens between 2 forested areas in Mississippi. Twin Oaks Wildlife Management Area (OAKS), located in the Mississippi Alluvial Valley, is a 2,302 ha tract of mature bottomland hardwood forest surrounded on 3 sides by soybean fields. Tallahala Wildlife Management Area (TWMA) is a 14,410 ha mixed forest in central Mississippi and is part of a large, forested ecosystem. Hens were captured, fitted with transmitters, and monitored by telemetry, 1990-1994 on TWMA (n = …

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Can Predator Trapping Improve Waterfowl Recruitment In The Prairie Pothole Region?, Frank C. Rohwer, Pamela R. Garrettson, Ben J. Mense Nov 1995

Can Predator Trapping Improve Waterfowl Recruitment In The Prairie Pothole Region?, Frank C. Rohwer, Pamela R. Garrettson, Ben J. Mense

Wildlife Damage Management Conference

We contrasted nest success for control areas and experimental areas in eastern North Dakota where we employed professionals to trap mammalian nest predators from late March to late July. In 1995, dabbling ducks averaged 53% nest success on four treatment blocks of 4,150 ha each; whereas on four control areas upland nesting ducks averaged 24% success. Diving duck nest success averaged 57% on experimental areas and 29% on control areas. American coot (Fulica americana) nest success also improved on experimental areas, but blackbird nesting and fledging success were not affected by the treatment In 1994, nest success of …

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Mississippi's Beaver Control Assistance Program, 1989-1994, Philip Mastrangelo Nov 1995

Mississippi's Beaver Control Assistance Program, 1989-1994, Philip Mastrangelo

Wildlife Damage Management Conference

Responding to landowner requests, the 1989 Mississippi Legislature created the Beaver Control Advisory Board and mandated it to develop a program which would ensure the control of beaver damage throughout Mississippi. The Advisory Board is comprised of the administrative heads of five state agencies: the Department of Wildlife, Fisheries, and Parks (chairperson), the Department of Transportation, the Cooperative Extension Service, the Forestry Commission, and the Department of Agriculture and Commerce. In cooperation with the U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Animal Damage Control (ADC) program, the Advisory Board developed the Beaver Control Assistance Program (BCAP). BCAP …

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Beaver Impacts On Timber On The Chauga River Drainage In South Carolina, J. Rickie Davis, Judy A. Barnes, George E. Ward, David Van Lear, David C. Guynn Jr., C. Andy Dolloff, Mark Hudy Nov 1995

Beaver Impacts On Timber On The Chauga River Drainage In South Carolina, J. Rickie Davis, Judy A. Barnes, George E. Ward, David Van Lear, David C. Guynn Jr., C. Andy Dolloff, Mark Hudy

Wildlife Damage Management Conference

Even though beavers (Castor canadensis carolinensis) occur over most of the southeastern United States, the impacts of increasing beaver populations on riparian forests within the southern Appalachian mountains are not been well documented. Long-term browsing and inundation by beaver may alter the composition and structure of riparian forests. A survey of 62 streams (74 mi) within the Chauga River drainage in the mountains of South Carolina was conducted during 1991- 1992 to determine the level of beaver activity within the drainage and the amount of timber damaged by beaver activities. Thirty-six streams had evidence of significant beaver activity …

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Rodent Damage Control In No-Till Corn And Soybean Production, Ron Hines Nov 1995

Rodent Damage Control In No-Till Corn And Soybean Production, Ron Hines

Wildlife Damage Management Conference

In recent years the primary cause of reduced plant stands in no-till crops planted into heavy residue has been small eared rodents called voles (Microtus spp.). Past research has indicated that severe stand reductions (80 to 100 percent) can occur if vole populations in the field exceed 75 per hectare (30 per acre) at planting time. This vole population should be considered intense. If field scouting about 30 days prior to planting reveals at least 12 active vole colonies per hectare (five per acre) an intense population can develop, and damage control measures should be planned. Of all …

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A Strategy For Integrating Principles And Concepts Of Wildlife Damage Control Into The School Curriculum, Thomas A. Eddy Nov 1995

A Strategy For Integrating Principles And Concepts Of Wildlife Damage Control Into The School Curriculum, Thomas A. Eddy

Wildlife Damage Management Conference

This paper reports an approach to educating today's youth concerning the importance of regulating numbers of wildlife species that threaten property, products and health. The emphases are on preparing teachers to integrate principles and concepts into the existing curricular materials, justifying control measures with ecological understandings and economic information and dealing effectively with sensitive animal rights issues. Opportunities for integration of specific wildlife damage control topics are suggested for lessons in the life sciences, social sciences, health, language arts and mathematics. Examples of conflict between groups of different opinions about the seriousness of a pest's activities or appropriateness of control …

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Wildlife Damage Control In Kansas: Private Operators And Public Agencies, L. Andrew Madison, Philip S. Gipson Nov 1995

Wildlife Damage Control In Kansas: Private Operators And Public Agencies, L. Andrew Madison, Philip S. Gipson

Wildlife Damage Management Conference

The private industry in wildlife damage control is expanding into territory predominantly occupied by public agencies in the past. There is a potential for overlap and competition in services provided by the public and private sectors in Kansas. We examined wildlife damage control activity reports from the Cooperative Extension Service (CES), Kansas Department of Wildlife and Parks (KDWP), and private nuisance wildlife control operators (NWCO) to determine the most common species controlled by each and their overlap in services across Kansas. The CES predominantly controlled coyotes (Canis latrans). KDWP primarily controlled beavers (Castor canadensis), deer ( …

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Closing Remarks: Seventh Eastern Wildlife Damage Management Conference, James E. Miller Nov 1995

Closing Remarks: Seventh Eastern Wildlife Damage Management Conference, James E. Miller

Wildlife Damage Management Conference

Initially, I want to begin these brief closing remarks by expressing appreciation to Dean Stewart, Phil Mastrangelo, Jim Armstrong, Greg Yarrow, other members of the Program Committee, all of the sponsors, exhibitors, contributors , speakers, and session moderators, and to all of you as participants who helped make this conference successful. As most of you who have ever had the privilege of putting together a conference such as this are well aware, there are always a number of people that are key to the success of the conference who work diligently behind the scenes but are not always recognized. We …

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Scanning Electron Microscopy Of Cyclosporine-Induced Gingival Overgrowth, Shahid H. Ashrafi, Krzysztof Slaski, Kyaw Thu, Eli S. Neiman, Michael P. Cunningham Oct 1995

Scanning Electron Microscopy Of Cyclosporine-Induced Gingival Overgrowth, Shahid H. Ashrafi, Krzysztof Slaski, Kyaw Thu, Eli S. Neiman, Michael P. Cunningham

Scanning Microscopy

Overgrown human gingival specimens were examined histologically and by scanning electron microscopy (SEM) to study structural changes caused by cyclosporine. The biopsy specimens were from organ transplant recipients receiving cyclosporine to suppress the rejection of the transplanted organ. The epithelium of the overgrown gingiva was thickened, acanthotic and parakeratotic. Retepegs were anastomosing and extending into connective tissue. The SEM examination of the outer surface of the attached gingival showed loss of cellular attachments and cells were exfoliating. The normal honeycomb structure formed by interconnecting microvilli surrounding the pits was distorted. Outer gingival cell surface showed numerous round, ovoid and dome-like …

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Examination Of Injected Specimens By Confocal Laser Scanning Microscopy And Scanning Electron Microscopy, A. Castenholz Oct 1995

Examination Of Injected Specimens By Confocal Laser Scanning Microscopy And Scanning Electron Microscopy, A. Castenholz

Scanning Microscopy

Although corrosion casts commonly examined by scanning electron microscopy (SEM) offer good insights into the general arrangement of the microvasculature of certain organs, no information can be obtained from such specimens on special morphological data or dynamic events. Thus, most investigators are obliged to make their interpretations of cast structures only on the basis of indirect criteria. A synopsis, which considers the most important data in that respect, is given for the blood and lymphatic microvessels. Moreover, a methodological approach is introduced, based on the application of fluorescent resin, which allows the examination of cast structures in uncorroded specimens together …

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Dietary Oxalate And Its Intestinal Absorption, Ross P. Holmes, Harold O. Goodman, Dean G. Assimos Oct 1995

Dietary Oxalate And Its Intestinal Absorption, Ross P. Holmes, Harold O. Goodman, Dean G. Assimos

Scanning Microscopy

Dietary oxalate is currently believed to make only a minor contribution (< 20%) to urinary oxalate excretion. A recent prospective study of stone disease suggested that dietary oxalate may be a significant risk factor. This observation led us to re-evaluate the contribution of dietary oxalate to urinary oxalate excretion. Previous studies have been hampered by inaccurate food composition tables for oxalate and inadequate methods for studying intestinal oxalate absorption. This evidence as well as factors that modify oxalate absorption are reviewed. New approaches to measure food oxalate and intestinal oxalate absorption have been examined. Capillary electrophoresis appears to be well suited for the analysis of the oxalate content of food. Two individuals consumed an oxalate-free formula diet for 7 days. This diet decreased urinary oxalate excretion by an average of 67% (18.6 mg per 24 hours) compared to oxalate excretion on self-selected diets. The absence of detectable oxalate in feces by day 6 of the diet suggested that the intestinal absorption was minimal. However, an effect of the formula diet on endogenous oxalate synthesis cannot be excluded. Restoring oxalate to the formula diet increased urinary oxalate excretion and illustrates that this experimental protocol may be well-suited for studying oxalate absorption and factors that modify it. Our results suggest that the intestinal absorption of dietary oxalate makes a substantial contribution to urinary oxalate excretion and that this absorption can be modified by decreasing oxalate intake or increasing the intakes of calcium, magnesium, and fiber.

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Elliptical-P Cells In The Avian Perilymphatic Interface Of The Tegmentum Vasculosum, C. D. Fermin, D. H. Lee, D. S. Martin Oct 1995

Elliptical-P Cells In The Avian Perilymphatic Interface Of The Tegmentum Vasculosum, C. D. Fermin, D. H. Lee, D. S. Martin

Scanning Microscopy

Elliptical cells (E-P) are present at the perilymphatic interface lumen (PIL) of the lagena. The E-P cells often separate from the tegmentum vasculosum (TV) and have touching processes that form a monolayer between the K+ rich perilymph and the Na+ rich endolymph, similar to the mammalian Reissner's membrane. We examined the TV of chicks (Gallus domesticus) and quantitated the expression of anti-S100ααββ and S100β. There was a 30% increase of S100β saturation in the light cells facing the PIL when compared to other TV light cells. We show that: (1) the dimer anti-S100ααββ and …

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Scanning Probe Microscope Gigahertz Measurements On 200 Nanometer Wave Guides, C. Böhm, J. Sprengepiel, E. Kubalek Oct 1995

Scanning Probe Microscope Gigahertz Measurements On 200 Nanometer Wave Guides, C. Böhm, J. Sprengepiel, E. Kubalek

Scanning Microscopy

Scanning probe microscopy is opening new applications in microelectronic engineering due to easy and reliable instrumentation in combination with superior resolution limits without any sample preparation under ambient conditions. Beside the standard topography imaging possible application are static and dynamic surface potential measurements, doping profiling, and scanning thermal applications. In this paper, we report dynamic voltage contrast measurements of analog and digital gigahertz signals on 200 nm wave guides within integrated microelectronic devices and components. The results are obtained by using a time resolved device internal test technique based on a scanning force microscope using the electrostatic force interaction. This …

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Penetration Of Positrons In Solid Targets, Maurizio Dapor Oct 1995

Penetration Of Positrons In Solid Targets, Maurizio Dapor

Scanning Microscopy

The study of the interaction of positron beams with solid targets has been approached by several investigators, also due to its importance for positron annihilation spectroscopy. This technique allows non-destructive investigations of the structural defects of surfaces and interfaces: in particular information is provided about the nature and distribution of point defects in solid materials. The solution of the diffusion equation, necessary to obtain the fractions of incident positrons annihilated at different depths inside the target, requires the knowledge of the positron stopping profile, i.e., the initial depth distribution of the thermalized positrons. Also transmission of positrons is of great …

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Atomic Force Microscopy Study Of Fine Structures Of The Entire Surface Of Red Blood Cells, P. -C. Zhang, C. Bai, Y. -M. Huang, H. Zhao, Y. Fang, N. -X. Wang, Q. Li Oct 1995

Atomic Force Microscopy Study Of Fine Structures Of The Entire Surface Of Red Blood Cells, P. -C. Zhang, C. Bai, Y. -M. Huang, H. Zhao, Y. Fang, N. -X. Wang, Q. Li

Scanning Microscopy

Glutaraldehyde-fixed red blood cells were imaged by tapping mode atomic force microscopy (TMAFM) in air at room temperature. The results show that TMAFM can visualize the morphology of the red blood cell at both cellular and nanometer scales. The scan size covers the range from several hundred nanometers to more than one hundred micrometers. TMAFM not only has a higher resolution than the optical microscope, but also can observe biological samples without precoating as required for scanning electron microscopy (SEM). The AFM images of the entire surface of an uncoated red blood cell with nanometer resolution are successfully reconstructed by …

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Vascular Architecture Of The Lactating And Non-Lactating Teat Of The Bitch: A Scanning Electron- And Light Microscope Study, F. J. Pérez-Aparicio, V. Dantzer, M. Navarro, A. Carretero, J. Ruberte Oct 1995

Vascular Architecture Of The Lactating And Non-Lactating Teat Of The Bitch: A Scanning Electron- And Light Microscope Study, F. J. Pérez-Aparicio, V. Dantzer, M. Navarro, A. Carretero, J. Ruberte

Scanning Microscopy

Tissues from fourteen mammary glands of eight bitches were prepared for scanning electron microscopy of vascular corrosion casts and for histology to study the vasculature of the lactating and non-lactating teats. The densely-meshed mammary dermal capillary network formed ridges and troughs. The teat ducts were vascularized by a relatively densely-meshed capillary network which drained into veins longitudinally oriented to the ducts. Between eight and fifteen teat duct openings were seen on the tip of the teat, that were sometimes divided by a septum. The inner vascularization of the teat showed that the main papillary arteries divided into undulating secondary papillary …

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Photoemission And Free Electron Laser Spectromicroscopy: Photoemission At High Lateral Resolution, G. Margaritondo Oct 1995

Photoemission And Free Electron Laser Spectromicroscopy: Photoemission At High Lateral Resolution, G. Margaritondo

Scanning Microscopy

The move of photoemission analysis from the macroscopic to the microscopic domain has been accelerated by the advent of new ultrabright synchrotron sources of soft-X-rays. This makes an overview of photoemission spectromicroscopy, photoemission at high lateral resolution, quite timely. The overview begins with the basic concepts and problems, both technical and of data-taking strategy. Then, it presents a small number of examples of results in physics and biology, such as local chemical fluctuations in superconductors, semiconductor interfaces and the microchemistry of biological systems. The presentation includes the first experimental results from two new ultrabright synchrotron facilities: ELETTRA (in Italy) and …

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