Life Sciences Commons^™

Imaging-Sims (Secondary Ion Mass Spectroscopy) Studies Of Advanced Materials, R. Levi-Setti, J. M. Chabala, J. Li, K. L. Gavrilov, R. Mogilevsky, K. K. Soni

Scanning Microscopy

This article describes the application of scanning ion microprobe (SIM) microanalysis for the characterization of advanced engineered materials. In conjunction with secondary ion mass spectrometry (SIMS), scanning ion microprobes can image elemental distributions over surfaces with high lateral resolution (50-100 nm). With this technique, most elements, including isotopes, can be detected with good sensitivity. The principles and instrumentation associated with the SIM/SIMS technique are briefly described and ongoing developments are outlined. The analytical capabilities of the technique are illustrated by case studies of aluminum-lithium alloys, zinc oxide varistors, aluminum matrix composites, and photographic materials.

Investigation Of Dislocations In Gaas Using Cathodoluminescence In The Scanning Electron Microscope, K. L. Pey, J. C. H. Phang, D. S. H. Chan

Scanning Microscopy

Electrically active dislocations in Si-doped {100} GaAs substrates were observed using the cathodoluminescence (CL) technique in the scanning electron microscope (SEM). CL contrast profiles were experimentally obtained from the dislocations at different beam energies. Based on the CL model for localized defects in semiconductors developed earlier by Pey, the depths of the dislocations were found by locating the beam energy at which maximum CL contrast occurred. A preferential etching technique for {100} GaAs was employed to reveal the dislocations and to measure their depths. The etched depths obtained were compared to the predicted results from the theoretical model developed. The …

Effects Of Ionizing Radiation On The Size Distribution Of Proteoglycan Aggregates Synthesized By Chondrocytes In Agarose, M. Cornelissen, H. Thierens, L. De Ridder

Scanning Microscopy

Effects of ionizing radiation on the structure and size-distribution of newly synthesized proteoglycan aggregates are studied in-vitro. Chondrocytes, isolated from embryonic chick sterna, are cultured for 7 days in a tri-dimensional agarose system. Single radiation doses of 10, 20 and 50 Gy are given before starting the culture. Digestion of the artificial agarose matrix liberates the newly synthesized proteoglycans. Spreading with cytochrome C allows electron microscopic investigations of the individual, newly synthesized molecules.

The structure of aggregates synthesized by control and irradiated chondrocytes is comparable. However, radiation causes alterations in the size-distributions of the aggregate-populations. For the control cultures, an …

Wood Anatomy And Relationships Of Santalaceae I. Acanthosyris, Jodina, And Myoschilos, Carlos Alejandro Norverto

Aliso: A Journal of Systematic and Floristic Botany

Study of the wood of Acanthosyris, Jodina, and Myoschilos confirmed a close relationship between Santalaceae and Olacaceae. Features important for defining the three genera and for determining relationships between them and with Schoepfia, which belongs to Olacaceae, are reported for the first time: vestured vessel walls, unilaterally compound pits, perforated ray cells, and druses.

A Phytochemical Study Of Selected Podostemaceae, Virginia Romo Contreras, Ron Scogin, C. Thomas Philbrick, Alejandro Novelo R.

Aliso: A Journal of Systematic and Floristic Botany

Podostemum ceratophyllum contains γ-mangostin and its 6-glucoside. The aglycone is also present in Marathrum, Oserya, and Vanroyenella, but is absent from Tristicha. Anthocyanins were identified from all genera, but no additional fiavonoids were detected. Condensed and hydrolyzable tannins, iridoids, cyanogenic glycosides, and alkaloids were lacking in all Podostemaceae examined. Phytochemical constituents do not clarify the uncertain systematic affinity ofPodostemaceae, but emphasize the generally accepted taxonomic isolation of this family.

A Review Of The Classification Of The Genus Hydrastis (Ranunculaceae), Carl S. Keener

Aliso: A Journal of Systematic and Floristic Botany

The genus Hydrastis has been variously classified as a monotypic taxon in the Ranunculaceae, the Berberidaceae, the Glaucidiaceae, or its own monogeneric family, the Hydrastidaceae. The objectives of this paper were 1) to review the previous classifications of Hydrastis and 2) to critique a recent paper by Tobe and Keating reevaluating the classification of the genus based on comparative morphological and anatomical studies. One conclusion of this review was that Tobe and Keating overlooked certain important papers which might have substantially altered their conclusions, viz., that Hydrastis is sufficiently distinct from the other genera of the Ranunculaceae to warrant a …

Agriculture News Release - 1993-12-30b, United States. Congress. House. Committee On Agriculture, E. De La Garza

Kika de la Garza Congressional Papers - Agriculture Committee News Releases

No abstract provided.

Quantitative Elemental Mapping Of Biomedical Specimens Using The Nuclear Microprobe., Jan Pallon, John Knox

Scanning Microscopy

Quantitative and structural elemental information is available from the nuclear microprobe through a time consuming fit of the (X-ray) spectrum at each point. An alternative technique is proposed which greatly shortens the analysis procedure and allows an increased number of samples to be processed. The method discussed here is to create elemental maps which, when they are divided by the charge/pixel and multiplied by a scaling factor, will form quantitative maps. The scaling factors are obtained from a calibration procedure comparing a large number of fitted X-ray spectra with the corresponding contents of selected energy windows. The technique also allows …

Ischemia/Reperfusion Injury Of The Ascending Colon In Ponies: A Correlative Study Utilizing Microvascular Histopathology And Corrosion Casting, B. J. Darien, P. A. Sims, W. C. Stone, D. R. Schilly, R. R. Dubielzig, R. M. Albrecht

Scanning Microscopy

Volvulus of the ascending colon (ACV) in the horse results in microvascular injury and necrosis of the intestinal mucosa. This study investigated the site and type of microvascular injury which occurs within the mucosa and sub mucosa following ACV. Histopathology of volvulus treated ponies demonstrated mucosa! necrosis with microvascular hemorrhage and thrombosis. Thrombi occurred within the subepithelial capillaries and edema and hemorrhage developed throughout the mucosa and submucosa. Vascular casts allowed 3-D viewing of samples obtained from the entire pelvic flexure and demonstrated two distinct microvascular changes: 1) disruption of the colonic glandular capillary network occurred concomitantly with the …

Wood Anatomy Of Sabiaceae (S.L.), Sherwin Carlquist, Peter L. Morrell, Steven R. Manchester

Aliso: A Journal of Systematic and Floristic Botany

Quantitative and qualitative data were offered for 30 taxa of Meliosma and one species each of Ophiocaryon and Sabia; qualitative data were available for additional species of Meliosma and Sabia. For a small family restricted to mesic sites, Sabiaceae had a wide range of wood anatomical expressions (e.g., long scalariform to simple perforation plates; heterocellular to homocellular multiseriate rays; tracheids, fiber-tracheids, or libriform fibers as imperforate tracheary elements; presence or absence of silica bodies and calcium oxalate crystals in rays). Growth ring type, vessel diameter, vessel density, and vessel element length were sensitively related to ecology, but to …

Laboulbeniales On Semiaquatic Heteroptera. Vi. The Genus Tavaresiella, Richard K. Benjamin

Aliso: A Journal of Systematic and Floristic Botany

Majewski's original circumscriptions of Tavaresiella (Laboulbeniales; Laboulbeniaceae; Stigmatomycetinae) and its type species, T. hebri, were emended in this study of the genus. In addition, three new species were described, T. majewskii, T. polhemi, and T. santamariae. These, like the type species, occurred on true bugs of the family Hebridae (Heteroptera). A key to the species was provided, and ali were described and illustrated with line drawings and photographs. Aspects of ascomatic structure and development were summarized, and the genus was compared with other genera of the subtribe having similar characteristics.

Improved Visualization Of Dna In Aqueous Buffer With The Atomic Force Microscope, Magdalena Bezanilla, Carlos J. Bustamante, Helen G. Hansma

Scanning Microscopy

An improved method has been developed for imaging deoxyribonucleic acid (DNA) in aqueous buffer with the atomic force microscope (AFM). DNA on untreated mica can be imaged in aqueous buffer with the AFM if the DNA is deposited onto the mica in a buffer with HEPES and MgCl₂, if the sample is rinsed thoroughly with high water pressure, and if the imaging is done with an electron beam-deposited (EBD) tip that has been deposited in the scanning electron microscope (SEM). The water rinse removes DNA that is otherwise easily scraped off the substrate. There is evidence that sharper …

Agriculture News Release - 1993-12-30a, United States. Congress. House. Committee On Agriculture, E. De La Garza

Kika de la Garza Congressional Papers - Agriculture Committee News Releases

No abstract provided.

X-Ray Microanalysis Of Camp-Induced Ion Transport In Ncl-Sg3 Sweat Gland Cells, Ann-Christin Mörk, Godfried M. Roomans

Scanning Microscopy

cyclic AMP (cAMP)-induced ion transport in a human sweat gland cell line, NCL-SG3, was investigated by X-ray microanalysis. Stimulation with cAMP caused a decrease in cellular Cl and K content in cells grown on impermeable as well as permeable supports. In cells grown on plastic coverslips or Transwell inserts stimulation with cAMP caused a significant decrease of the Na concentration, but no significant effect on the intracellular Na was seen on cells grown on grids. cAMP had no significant effect on the intracellular Ca concentration.

Effects Of Modulated And Continuous Microwave Irradiation On Pyroantimonate Precipitable Calcium Content In Junctional Complex Of Mouse Small Intestine, Z. Somosy, G. Thuróczy, J. Kovács

Scanning Microscopy

The pyroantimonate precipitable calcium content of intestinal epithelial cells was investigated in mice following total body irradiation with 2450 MHz continuous and low frequency (16 Hz) square modulated waves. In the control animals the reaction products appeared in the intercellular space of adjacent cells including intermediate junctions and desmosomes and were absent in the area of tight junctions. Immediately after low frequency modulated microwave irradiation at 0.5 and 1mW/cm² power densities, a rapid distribution of pyroantimonate precipitable calcium content was observed. The pyroantimonate deposits were located on the cytoplasmic side of lateral membrane, in the area of junctional complex, …

Caesium On Si(100) Studied By Biassed Secondary Electron Microscopy, M. Azim, C. J. Harland, T. J. Martin, R. H. Milne, J. A. Venables

Scanning Microscopy

An ultra-high vacuum scanning electron microscope (UHV-SEM) has been used to study sub-monolayers of Cs on Si(100) surface. Cs adsorption on the surface causes a considerable change in the work function. Coverages below 1/2 monolayer (ML) have been estimated by correlating the work function changes with the secondary electron (SE) signal. It has been found that this signal is sensitive down to ~ 0.005 ML when the sample is biassed to a few hundred volts.

Electron trajectories from a biassed sample have been simulated for electrons originating from different areas with different work functions across the sample. This indicates that …

Calcium Phosphate In Aspergillosis Of The Maxillary Sinus, Hidekuni Tanaka, Toshiro Sakae, Hiroyuki Mishima, Hirotsugu Yamamoto

Scanning Microscopy

The unique appearance of apatite in fungus balls of aspergillosis in the maxillary sinus was investigated using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), X-ray microdiffraction and Fourier transform infrared spectroscopy (FT-IR). Rod-shaped fragments with tubular structures, and globular vesicles covered with conidia were observed in the fungus balls. Massive fragments of a solid substance were demonstrated inside the fungus balls. Calcium and phosphate were detected in necrotic areas of the fungus balls by EDS. X-ray microdiffraction and FT-IR showed the presence of an apatite-like substance, but failed to demonstrate the presence of calcium oxalate crystals usually found in such …

Optimization And Application Of Jet-Freezing, T. Müller, S. Moser, M. Vogt, C. Daugherty, M. V. Parthasarathy

Scanning Microscopy

Cryofixation is considered to be the best method for immobilizing biological material in its natural state. In jet-freezing, the specimen typically is sandwiched between two carriers and kept in place while a coolant is moved very rapidly against the opposite surfaces. The JFD 030 jet-freezing device has been used to optimize the operating parameters. The course of the temperature in place of a specimen was measured with thermocouples and recorded by an IBM-compatible personal computer using a specifically developed software program. Mean cooling rates, over the temperature range of 273K to 173K, achievable with different cryogens, including the non-flammable HCFC …

Scanning Electron Microscopy Of High-Pressure-Frozen Sea Urchin Embryos, Paul Walther, Ya Chen, Marek Malecki, Sara L. Steffen Zoran, Gerald P. Schatten, James B. Pawley

Scanning Microscopy

High-pressure-freezing permits direct cryo-fixation of sea urchin embryos having a defined developmental state without the formation of large ice crystals. We have investigated preparation protocols for observing high-pressure-frozen and freeze-fractured samples in the scanning electron microscope. High-pressure-freezing was superior to other freezing protocols, because the whole bulk sample was reasonably well frozen and the overall three-dimensional shape of the embryos was well preserved. The samples were either dehydrated by freeze-substitution and critical-point-drying, or imaged in the partially hydrated state, using a cold stage in the SEM. During freeze-substitution the samples were stabilized by fixatives. The disadvantage of this method was …

Penjual Obat Aborsi Di Lampung Daae339f Jual Obat Telat Bulan Di Bandar Lampung, Cahayarahmawati08 Rey

Alamat Klinik Aborsi Di Lampung DB7BE24E Aborsi Wilayah Lampung

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• KEHAMILAN YANG DI SEBABKAN KORBAN PERKOSAAN.
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• KEHAMILAN YANG TIDAK DAPAT DI TERUSKAN KARENA …

Obat Aborsi Asli Di Cikarang Daae339f Jual Obat Aborsi Apotek Cytotec Di Kota Cikarang, Bang Rey

Jual Obat Aborsi Ampuh Di Karawang DB7BE24E Obat Aborsi Cytotec Di Kota Karawang

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• KEHAMILAN YANG DI SEBABKAN KORBAN PERKOSAAN.
• KEHAMILAN DILUAR NIKAH DAN PACAR ANDA TIDAK BERTANGGUNG JAWAB.
• KEHAMILAN YANG TIDAK DAPAT DI TERUSKAN KARENA ALASAN …

Evolutionary Perspectives On Animalivory, Patricia W. Freeman

University of Nebraska State Museum: Mammalogy Papers

Derived from insectivorous ancestors, microchiropteran bats have diversified into a remarkable array of feeding habits. Cranial and dental characteristics mirror this diversity. Insectivorous predators of hard-shelled prey have thicker jaws, well-developed cranial crests, fewer but larger teeth, longer canines and abbreviated M3s than species that take soft items. Carnivorous bats have more elongate skulls, larger brain volumes and larger pinnae, lengthened metastylar ridges, and larger protoconids compared to insectivores. Animalivorous species have large ectoloph areas compared to frugivorous and nectarivorous species, but animalivores and frugivores have large tooth areas relative to palatal area compared to nectarivores. Frugivores sacrifice ectoloph for …

Jual Obat Aborsi Bintuni 08127092708 Klinik Aborsi Penjual Obat Aborsi Cytotec Di Bintuni, Wiwit Bintuni

Wiwit Bintuni

Northeast Research Station Watertown, South Dakota Annual Progress Report, 1993, Agricultural Experiment Station, Plant Science Department

Agricultural Experiment Station and Research Farm Annual Reports

This is the 1993 annual progress report for the Northeast Research Station in Watertown, South Dakota. This report is issued by the South Dakota Agricultural Experiment Station and the South Dakota State University Plant Science Department. This report includes information on the 1993 crop season, including growing season precipitation data from 1956-1993, information on the wheat scab epidemic of 1993, crop performance trials, oat and rye research, spring wheat breeding, alfalfa yield test and breeding for wildlife habitat, soybean studies, W.E.E.D. project demonstration, farming system studies, 1993 yields, soil moisture and soil tests results, and soybean breeding.

Micro-Pixe (Particle Induced X-Ray Emission) Analysis Of Aluminum In Rat-Liver Using Mev Heavy Ion Microprobes, Yuji Horino, Yoshiaki Mokuno, Atsushi Kinomura, Kanenaga Fujii, Sakae Yumoto

Scanning Microscopy

Heavy ion microprobes (HIM) such as 3 MeV Si²⁺ and 3 MeV p²⁺ have been applied to the elemental analysis by PIXE (proton-induced X-ray emission). It was found that silicon and phosphorus microprobes have several times higher sensitivity for aluminum Kα X-rays than 2 MeV proton microprobes, and detection limits were more favorable in a phosphorus microprobe. Using a 3 MeV p²⁺ microprobe, the liver of a rat, which had been injected with aluminum-lactate, was investigated and it was found that aluminum segregates in areas with a dimension of about 10 μm. These areas could hardly be …

Avicennia Germinans (L.) Stearn, Steven R. Hill, D. Bradshaw, I. Renne

Specimens by Name

No abstract provided.

Intracellular And Extracellular Elemental Composition Of The Endolymphatic Sac Studied By X-Ray Microanalysis, Romuald Wroblewski

Scanning Microscopy

X-ray microanalysis was performed along with light microscopy (LM) on rapidly frozen and cryo-sectioned endolymphatic sac tissues of adult guinea pigs, to determine the elemental composition of the different cell types in this tissue as well as the content of the sac lumen. The morphological preservation and spatial resolution of cryo-sectioned endolymphatic sac was found adequate for the identification of the different cell types of the sac in the transmission electron microscope. Further cell type identification was performed by comparing scanning transmission electron microscopy images with LM images on adjacent serial sections. X-ray microanalysis demonstrated differences between epithelial and sub-epithelial …

Agriculture News Release - 1993-12-09, United States. Congress. House. Committee On Agriculture, E. De La Garza

Kika de la Garza Congressional Papers - Agriculture Committee News Releases

No abstract provided.

Agriculture News Release - 1993-12-08, United States. Congress. House. Committee On Agriculture, E. De La Garza

Kika de la Garza Congressional Papers - Agriculture Committee News Releases

No abstract provided.

The Meat Consumer Today - Price: Is It Time For A New Strategy?, Pat Swan

Range Beef Cow Symposium

When determining the purchasing behavior of today's consumer, one should realize that price is but one factor in the buying decision. This tenet applies to meat producers, packers, and retailers alike, many of whom are beginning to look at the definition of price in a different way. There are, in fact, two ways of looking at price: from the "inside out" and the "outside in". When pricing is determined by the "inside out" method, the emphasis is on recovering the initial production costs and the addition to those costs to generate a profit. The "outside in" approach to pricing, however, …