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Articles 37981 - 38010 of 39871
Full-Text Articles in Entire DC Network
Communication Networks And The Adoption Of Three Farn Practices, P. W. Fry, F. K. Goss
Communication Networks And The Adoption Of Three Farn Practices, P. W. Fry, F. K. Goss
All other publications
The report commences with a discussion of the diffusion and adoption model, and illustrates some of the research observations and practical outcomes that have emerged in recent years, An overview of social network research is presented as a means of understanding communication exchanges and providing data relevant to the diffusion debate. The communication and adoption studies are then reported in three separate sections in the order they were conducted. (A map of the location of the survey areas is shown in Figure I ) . The objectives, survey method, results and a summary are presented for each study.
A background …
Production Of Monoclonal Antibodies Specific For The Microgametocytes Of Eimeria Tenella, Marc A. Laxer
Production Of Monoclonal Antibodies Specific For The Microgametocytes Of Eimeria Tenella, Marc A. Laxer
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The objective of this study was to produce a monoclonal antibody specific for the microgametocytes of Eimeria tenella, examine the site and stage specificity of the antibody, and investigate the immunopotency of the antibody. BALB/c mice were immunized with antigen containing Eimeria tenella microgametocytes isolated from in vitro systems. After three intraperitoneal immunizations with the antigen and one booster immunization administered by tail vein injection, the mice were sacrificed and their spleen cells fused with SP2/0 mouse myeloma cells using polyethylene glycol as a fusing agent. Resultant hybridomas were screened by immunoelectrophoresis, indirect immunofluorescent antibody assay, and immunoelectron microscopy …
Effect Of Iron On Residual Nitrite Level In Ground Pork And Model Systems, Changmin Kim
Effect Of Iron On Residual Nitrite Level In Ground Pork And Model Systems, Changmin Kim
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The effects of iron, temperature, and presence of botulinal spores or sodium ascorbate on depletion of nitrite level were determined in meat and model systems. Higher temperature and presence of botulinal spores definitely increased nitrite depletion in a meat system. Added hemoglobin also significantly increased nitrite depletion, while ferrous iron and ferric iron did not significantly decrease nitrite level in a meat system. High temperature and presence of sodium ascorbate increased nitrite depletion in a model system. Only ferrous iron significantly decreased nitrite level in the absence of ascorbate, while ferric iron, heme iron, and ferritin iron did not decrease …
Effects Of Bulk Starter Media And Proteolytic Lactic Streptococci On Protein Loss In Cheddar Curd Manufacture, Steven A. Winkel
Effects Of Bulk Starter Media And Proteolytic Lactic Streptococci On Protein Loss In Cheddar Curd Manufacture, Steven A. Winkel
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The effects of whey-based and milk-based starter media, and low concentrations (0.02% each) of citrate, phosphate and calcium upon various milk coagulation properties were measured. Samples inoculated with milk-based starter medium had shorter coagulation times, faster rate of curd formation, and greater final curd firmness than those inoculated with externally neutralized whey-based starter. Starter medium treatment was statistically interacted with calcium for coagulation time and rate of curd formation. Citrate addition caused longer coagulation times, slower rates of curd formation, and weaker final coagula. Citrate interacted with calcium and phosphate for several of the parameters measured. Addition of phosphate did …
Reduction Of Sodium Nitrite And Sodium Chloride In A Cured Meat Product By Using Acid Development To Inhibit Botulinal Toxin Formation, Angsana Assamongkorn
Reduction Of Sodium Nitrite And Sodium Chloride In A Cured Meat Product By Using Acid Development To Inhibit Botulinal Toxin Formation, Angsana Assamongkorn
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Pediococcus acidilactici as a lactic acid producer, and sucrose were added to breakfast strip products in order to reduce added levels of sodium nitrite and sodium chloride and yet limit the growth of Clostridium botulinum and inhibit toxin production. Sucrose at 0.4 or 0.9% with P. acidilactici at 1.0 x 108 cells/g were added during preparation of breakfast strip products prepared with combinations of 40 or 80 ppm sodium nitrite and 1.0 or 2.0% sodium chloride. Other ingredients were added at levels normally used in cured meat products. C. botulinum types A and B at 1,000 spores/g were inoculated …
Coprecipitation Of Phosphorus With Calcium Carbonate In Bear Lake, Utah - Idaho, Paul W. Birdsey Jr.
Coprecipitation Of Phosphorus With Calcium Carbonate In Bear Lake, Utah - Idaho, Paul W. Birdsey Jr.
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Monitoring of Bear Lake was conducted in 1981 and 1982 to describe the current limnology and trophic state of the lake. The nutrient loadings of various parameters were measured from April, 1981 through June, 1982. The rate of coprecipitation of phosphorus was determined for different initial phosphorus concentrations by use of non-algal assays. Algal bioassays with Selenastrum capricornutum were used to determine the reduction in potential algal biomass as a result of the coprecipitation of phosphorus.
The lake exhibited chemical characteristics indicative of mesotrophy or eutrophy. Total phosphorus values averaged 11μg/1 for 1981 and 20 μg/1 for 1982. A hypolimnetic …
Summary Of The Results Of Analysis Of Obsidian Artifacts From The Maya Lowlands, F. W. Nelson
Summary Of The Results Of Analysis Of Obsidian Artifacts From The Maya Lowlands, F. W. Nelson
Scanning Electron Microscopy
The analytical method of X-ray fluorescence spectrometry has been used to analyze obsidian artifacts from Cerros, Belize and from Yaxchilan, Chiapas, Mexico. The results of these analyses are compared to the results of analysis of obsidian geologic sources using graphical and statistical methods in order to identify the probable source from which the obsidian for the artifacts came. These results are then summarized along with results of analysis by others of obsidian artifacts from several archaeological sites in the Lowland Maya area. Using these data, possible trade routes and how they may have changed through time have been postulated.
One Man’S Beef, William Severini Kowinski
One Man’S Beef, William Severini Kowinski
Profiles
Henry Spira believes that animals have rights but no say. He speaks for all species.
The Gamut: A Journal Of Ideas And Information, No. 15, Spring/Summer 1985, Cleveland State University
The Gamut: A Journal Of Ideas And Information, No. 15, Spring/Summer 1985, Cleveland State University
The Gamut Archives
CONTENTS OF ISSUE NO. 15, SPRING/SUMMER, 1985
Robert Finn: Learning to Enjoy Today's Music, 2
Getting past Stravinsky and Mahler to the hard stuff
James C. Haden: Stoning Socrates, 12
A philosopher looks at I. F. Stone's revisionist view of Socrates
William F. Lyon: Fireflies llluminate Life Processes, 23
Perhaps you should have kept those lightning bugs you used to catch on hot summer nights
John F. Donoghue: Two Poems, 26
"Space-Time and Sinkers" and "Concerto"
Louis T. Milic: Giving Away $1,000,000 a Year, 28
Stewart R. Mott's individualized philanthropy
David Sheskin: Four Drawings, …
Integration Of X-Ray Microanalysis And Morphometry Of Biological Material, W. C. De Bruijn
Integration Of X-Ray Microanalysis And Morphometry Of Biological Material, W. C. De Bruijn
Scanning Electron Microscopy
It was investigated how to extract both morphometrical and X-ray elemental information from scanning electron microscopical (SEM) or scanning transmission electron microscopical (STEM)-images and how to integrate these two information streams either on line or off-line after storage.
Cytochemical reaction products in cell organelles in ultrathin sections are the biological structures of interest. In such organelles four different situations can be met: morphologically the structures are homomorph or heteromorph; chemically the elements are distributed either homogeneously or heterogeneously. A new program has been proposed and described, which permits determination of both the area and the mean net-intensity value of chemical …
Calmodulin Levels In The Yeast And Mycelial Phases Of Ceratocystis Ulmi, Ganapathy Muthukumar, Rajiv K. Kulkarni, Kenneth W. Nickerson
Calmodulin Levels In The Yeast And Mycelial Phases Of Ceratocystis Ulmi, Ganapathy Muthukumar, Rajiv K. Kulkarni, Kenneth W. Nickerson
Papers in Microbiology
The calmodulin content of the yeast and mycelial phases of Ceratocystis ulmi was determined by radioimmunoassay. Calmodulin levels increased at the G1-S boundary of the cell cycle, coinciding with the first visible appearance of buds or germ tubes. However, in both phases the cellular calmodulin levels were equivalent. No differential synthesis was observed.
Louisiana Agriculture Magazine, Spring 1985, Lsu Agricultural Experiment Station
Louisiana Agriculture Magazine, Spring 1985, Lsu Agricultural Experiment Station
Louisiana Agriculture
No abstract provided.
Partial Purification And Characterization Of A Polysaccharide Depolymerase Associated With Phage-Infected Erwinia Amylovora, Peter A. Vandenbergh, Ann M. Wright, Anne K. Vidaver
Partial Purification And Characterization Of A Polysaccharide Depolymerase Associated With Phage-Infected Erwinia Amylovora, Peter A. Vandenbergh, Ann M. Wright, Anne K. Vidaver
Department of Plant Pathology: Faculty Publications
Erwinia amylovora infected with bacteriophage ERA103 produced an enzyme which degraded the extracellular polysaccharide of noninfected cells. The depolymerase enzyme was purified 15-fold by a procedure which included ammonium sulfate precipitation, ultracentrifugation, CM-Sephadex batchwise separation, Sephadex G-50 column chromatography, and Sephacryl S-200 column chromatography. The enzyme had a molecular weight of approximately 21,000 and a pH optimum of 6.0. Activity was enhanced by supplements of 2-mercaptoethanol or dithiothreitol.
A Study Of Cell-Mediated Immunity During A Primary Infection With Pseudorabies Virus, John George Chosay
A Study Of Cell-Mediated Immunity During A Primary Infection With Pseudorabies Virus, John George Chosay
Masters Theses
This research defines the role and sequence of cell-mediated immune events in an in vivo virus infection. Pseudorabies virus infected CF1 mice lungs, were assessed by his to logical or immunohistochemical means. Using fluorescein isothiocyanate Tabled anti-T lymphocyte (ATG) and lissamine rhodamineB200 labeled anti-macrophage globulins (AMG), the number of lymphocytes and macrophages were determined. An early increase in T cells (four hours post-innoculation) was followed by an increase in macrophages (15 hours post-innoculation). Thereafter tissue levels of T cells and macrophages remained constant. Thymus dependent lymphocyte; failed to show increase macrophages clustering as pathology progressed. The first pathological changes in …
X-Ray Microanalysis Of Biological Tissues - An Examination Of Comparative Specimen Preparation Techniques Using Prostatic Tissue As A Model, J. A. Chandler
X-Ray Microanalysis Of Biological Tissues - An Examination Of Comparative Specimen Preparation Techniques Using Prostatic Tissue As A Model, J. A. Chandler
Scanning Electron Microscopy
A number of reproductive tissues have been investigated by X-ray microanalysis for a large number of elements. These elements occur both free and with many different forms of binding to tissue proteins and cellular constituents. The prostate tissue studied here represents a glandular tissue with both parenchymal and stromal components having different cell types. While no general rule can be applied to the preparative technique for all tissues, it would seem that of all the methods examined here freeze substitution or the use of dehydration fluids combined with subsequent embedding offer the most promising compromise between cryoultramicrotomy and aqueous fixation.
The Chrysis Gibba Species Group In The New World (Hymenoptera, Chrysididae), R. M. Bohart
The Chrysis Gibba Species Group In The New World (Hymenoptera, Chrysididae), R. M. Bohart
Insecta Mundi
The gibba group of Chrysis occurs in many parts of the world. It is characterized in part by a lengthened clypeus. Other features are the usually long malar space, micro-ridging on the scapal basin, a frontal carina (when developed) with a broad M-shape and partial posterior rami (broadly biconvex in one species), tergum II apicolaterally obtuse, and tergum III with 4 teeth or lobes. American forms in the male, and to lesser extent the female, have long whitish hair beneath the head and on the opposing surface of the forecoxae. Other legs are also quite hairy, especially in males. Sternum …
The Growth Of Fetal Human Sensory Ganglion Neurons In Culture: A Scanning Electron Microscopic Study, Seung U. Kim, Kookmin M. Kim, Giuseppe Moretto, James H. Kim
The Growth Of Fetal Human Sensory Ganglion Neurons In Culture: A Scanning Electron Microscopic Study, Seung U. Kim, Kookmin M. Kim, Giuseppe Moretto, James H. Kim
Scanning Electron Microscopy
Sensory neurons of 8-week human fetal dorsal root ganglia were dissociated into single cells by trypsinization and cultured on coverslips for 4 months, in either serum-containing or serum-free chemically defined media. At different times the cultures were fixed and prepared for scanning electron microscopy. Fetal sensory neurons in culture regenerated axons within 24 hours which were characterized by axonal growth cones at their tips and the neuronal perikarya assumed spherical or a bonnet-like morphology.
Freeze-Drying And Related Preparation Techniques For Biological Microprobe Analysis, Romuald Wróblewski, Joanna Wróblewski, Matti Anniko, Lars Edström
Freeze-Drying And Related Preparation Techniques For Biological Microprobe Analysis, Romuald Wróblewski, Joanna Wróblewski, Matti Anniko, Lars Edström
Scanning Electron Microscopy
An X-ray microanalytical and morphological investigation has been carried out on rapidly frozen, freeze-dried or freeze-substituted tissues. A comparison was made between different embedding and polymerisation procedures following freeze-substitution and freeze-drying. The investigation also included an analysis of specimens infiltrated, embedded and polymerised by ultraviolet irradiation at low temperatures with Lowicryl HM20. The morphological preservation of Lowicryl embedded tissue was adequate for the identification of different cell structures like nuclei, mitochondria, lysosomes and different types of endoplasmic reticulum. X-ray microanalytical investigation of low temperature embedded material displayed an elemental composition of cells and organelles similar to that found in freeze-dried …
Ultrastructural Studies Of Crystal-Organic Matrix Relations In Renal Stones, P. -T. Cheng, A. D. Reid, K. P. H. Pritzker
Ultrastructural Studies Of Crystal-Organic Matrix Relations In Renal Stones, P. -T. Cheng, A. D. Reid, K. P. H. Pritzker
Scanning Electron Microscopy
Biochemically the organic matrix of kidney stones contains mucoproteins, mucopolysaccharides, inorganic material and bound water. Morphologically, the organic matrix exists as either amorphous or fibrous forms. We have attempted to critically evaluate results from analytical and morphological studies on stone matrices using light microscopy, histochemistry, x-ray diffraction, scanning electron microscopy, x-ray energy dispersive spectrometry, transmission electron microscopy and selected area electron diffraction.
On the surface of calcium oxalate stones, there are usually large masses of randomly deposited calcium oxalate crystals each coated with organic matrix. Transmission electron microscopy shows these large surface crystals are composed of rows of smaller crystallites …
Estimates Of Soil Solution Ionic Strength And The Determination Of Ph In West Australian Soils, P. J. Dolling, G. S.P. Ritchie
Estimates Of Soil Solution Ionic Strength And The Determination Of Ph In West Australian Soils, P. J. Dolling, G. S.P. Ritchie
Food Science and Nutrition
The average ionic strength of 20 West Australian soils was found to be 0.0048. The effects of three electrolytes (deionized water, CaCl2 and KNO3), three ionic strengths (0.03, 0.005 and soil ionic strength at field capacity, Is) and two soil liquid ratios (1:5 and 1:10) on the pH of 15 soils were investigated. pH measurements in solutions of ionic strength 0.005 differed the least from measurements made at Is. The differences that occurred in comparisons with distilled water or CaCl2 of ionic strength 0.03 (0.01 M) were much greater (≥0.4 pH …
A Microecosystem For Fertilizer And Pesticide Fate Research, B. E. Branham, David J. Wehner, W. A. Torello, A. J. Turgeon
A Microecosystem For Fertilizer And Pesticide Fate Research, B. E. Branham, David J. Wehner, W. A. Torello, A. J. Turgeon
Office of the Dean (CAFES) Scholarship
A microecosystem was designed to study the behavior of pesticides, fertilizers, or related compounds applied to plant stands. The system consists of three parts: a brass base that holds the plant growth media, a glass atmospheric chamber that rests on the base, and a set of analytical traps. The brass base is fitted with a porous ceramic plate so that tension can be applied to the water in the growing media. Air enters the bottom of the glass atmospheric chamber and exits through the top into appropriate trapping systems to recover volatilized pesticides, ammonia, or metabolized 14CO2 from …
Foliar Diseases Of Wheat., R. Loughman
Foliar Diseases Of Wheat., R. Loughman
Experimental Summaries - Plant Research
Glasshouse screening for resistance to septoria nodorum and pyrenophora tritici repentis. Assessment of Interstate Variety Trial 'B' 1985. Glasshouse assessment of a novel selection technique. Duration of leaf wetness incubation as it affects glasshouse screening. Effect of leaf disease in multiple wheat cropping. M1, M2, E1, E2, E3. An inoculum for inducing s. Nodorum epidemics in the field.
Summary Of Rhizobium Experiments., J G. Howieson
Summary Of Rhizobium Experiments., J G. Howieson
Experimental Summaries - Plant Research
The screening of 33 isolates of R. meliloti collected in Sardinia in 1984, and isolated on a low pH medium, 84ME33. Assessment of the possibility of establishing an 'Index of Symbiotic Competence' for species of Medicago, 85M57. Assessment of the effectiveness of several strains of R. meliloti on M.littoralis, and their saprophytic competence in an acid soil, 84ME35. The screening of the pre-1984 collection of R.meliloti held at the W.A. Department of Agriculture for acid tolerance, 84M34. Assessment of the survival of the Serena WSM419 symbiosis on a range of soil types, 84ME32, 84WH24, 84N18. Assessment of the acid tolerance …
Physics Of The Preparation And Observation Of Specimens That Involve Cryoprocedures, E. Kellenberger, E. Carlemalm, W. Villiger
Physics Of The Preparation And Observation Of Specimens That Involve Cryoprocedures, E. Kellenberger, E. Carlemalm, W. Villiger
Scanning Electron Microscopy
With this introductory chapter we attempt a synthesis of old and new knowledge of the physical principles that govern cryomethods. Interface phenomena determine the increase or decrease of the number of particles observed in frozen-hydrated suspensions because they occupy the air-liquid interface according to their specific balance of hydrophobic versus hydrophilic properties. Biological macromolecules are surrounded by organised water, the hydration shell, that prevents them from sticking to each other. Partial or complete removal of these hydration shells by freeze-drying or freeze-substitution leads to collapses or aggregations. The solvent-induced aggregation is usually decreased by prior cross-linking with adequate chemical fixatives. …
Fungicides For Control Of Pythium Ultimum On Greenhouse-Grown Geraniums, Nancy L. Olson, F. L. Phleger
Fungicides For Control Of Pythium Ultimum On Greenhouse-Grown Geraniums, Nancy L. Olson, F. L. Phleger
Journal of the Minnesota Academy of Science
Subdue 2E applied by drench at 18.7 ppm to soil inoculated with Pythium ultimum and in which rooted cuttings of geranium had been planted, was found to be free of the fungus during the test period of 30 days and caused no injury to the plants. Banrot 40W at 240 ppm and Truban 25E at 145 ppm were only slightly fungistatic.
Cryofixation And Cryosubstitution For Routine Work In Transmission Electron Microscopy, H. Sitte, K. Neumann, L. Edelmann
Cryofixation And Cryosubstitution For Routine Work In Transmission Electron Microscopy, H. Sitte, K. Neumann, L. Edelmann
Scanning Electron Microscopy
After a brief review of the present state of the theory of cryofixation, methods and instruments as well as criteria for the application of cryofixation and cryosubstitution in daily routine work in cell biology and medicine are described. Good results are obtainable using liquid nitrogen for impact freezing on highly polished copper surfaces or by plunging into liquefied propane. Based on these results a versatile and safe system for routine plunging and impact freezing for the majority of biomedical objects has been developed. In order to enable ultramicrotomy at ambient temperature a cryosubstitution system according to the Edelmann principle has …
The Performance Of Gazania Splendens Cultivars Under Kentucky Conditions, Ellen Sue Justiss
The Performance Of Gazania Splendens Cultivars Under Kentucky Conditions, Ellen Sue Justiss
Masters Theses & Specialist Projects
Gazania splendens is a tender, herbaceous perennial that belongs to the Compositae family. The leaves are green and glabrous above, white tomentose beneath, toothed, simple and/or pinnatifid, 4”-6” long tapering to a winged petiole, lanceolate to obovate-lanceolate, and arranged in a basal clump. The flower heads are large, showy, 2”-3” in diameter, and range in color from white to yellow, orange, pink, purple, ruby, and bronze with a dark ring or spot at the base of most.
Twelve cultivars of Gazania splendens were to be evaluated to determine which would perform the best under Kentucky conditions. A seed germination test …
Alternatives To Aversive Procedures With Animals In The Psychology Teaching Setting, Jeffrey A. Kelly
Alternatives To Aversive Procedures With Animals In The Psychology Teaching Setting, Jeffrey A. Kelly
Experimentation Collection
In this paper, we will consider the treatment of laboratory animals in psychology instruction and will focus on practical alternatives to traditional practices that cause pain and distress to animals. While the discussion will draw on psychology for examples, many of the issues apply equally to the instruction of students in other courses of study, including medicine, veterinary medicine, biology, and physiology.
The Glass Knife In Ultramicrotomy, Lahja Sevéus, Cecilia Tarras-Wahlberg
The Glass Knife In Ultramicrotomy, Lahja Sevéus, Cecilia Tarras-Wahlberg
Scanning Electron Microscopy
To obtain the best ultrathin sections in ultramicrotomy and cryoultramicrotomy, a high quality knife is of paramount importance. Glass knives were introduced for ultramicrotomy, in the manually broken form, in 1950. Since the introduction of mechanical knifemakers, the production of glass knives has become a standardized laboratory routine. In conventional ultramicrotomy different knife angles are used to cover different specimens and embedding media. The 50° knife broken with a small deviation of the score from the diagonal of the square gives a long useful edge, especially if damping during breaking is used. The 50° knife is, therefore recommended as the …
Freeze Substitution And Low Temperature Embedding, B. Humbel, M. Müller
Freeze Substitution And Low Temperature Embedding, B. Humbel, M. Müller
Scanning Electron Microscopy
The problems of conventional EM-preparation techniques based on chemical fixation may be overcome to a considerable extent by freeze substitution techniques. Although at present substitution cannot be performed at sufficiently low temperatures to prevent the recrystallization of vitrified aqueous specimens, thin sectioned biological samples show an improved information density. If freeze-substitution is combined with conventional embedding above 273 K (Epon/Araldite, Spurr's resin) the substituting organic solvent must contain stabilizing agents such as osmiumtetroxide, glutaraldehyde or uranylions. In combination with low temperature embedding procedures (Lowicryl) completely unfixed samples are obtained, which are suitable for immunolabelling and electron spectroscopic experiments. Water in …