bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increased Candida Demonstrated in Subgingival Plaques of Aids Patients by Microwave-Accelerated Silver Staining
Authors: Hanker Jacob S. , Kutcher Mark J. , Burkes E. Jefferson , Greco George W. , Hopfer Roy L. , Hamamoto Darryl T. , Webster William P. , Yates Peggy E. , Beck James D. , Giammara Beverly L. 
Published: March 2011

ABSTRACTAcute periodontal lesions generally respond to conventional therapy. In AIDS patients, however, further deterioration is the usual consequence. Candida albicans(CA) lesions of the oral mucosa have been observed in 88% of AIDS patients; 59% of male homosexual and IV drug abuser oral candidiasis patients subsequently developed AIDS. Indeed HIV may be hard to find in AIDS patients in whom CA lesions are very prominent.Rapid reproducible silver stains have been developed in our laboratories to detect Gram-negative bacteria, fungi and protozoa. They demonstrate these microorganisms by the microwave-accelerated metallization of the aldehydes produced in their surface carbohydrates or lipopolysaccharides after periodic acid oxidation (Giammara and Hanker, US Patent No. 4,690,901, 1987; Sigma Diagnostics Kit No. HT-100). We thought that these stains might be useful to demonstrate by microscopy the large numbers of CA which culture studies had suggested were present in subgingival plaque at atypical periodontal disease sites of AIDS patients. Direct staining of plaque smears and their evaluation under the light microscope could be done in much less time than that required for culture. Any equivocal microorganisms could be positively identified as CA by immediate examination of the slide or coverslip by scanning electron microscopy. Although our PATS reaction was more valuable for identifying Gram-negative bacteria especially spirochetes and for studying substructure of CA and their epiphytic interactions with bacteria, the SIGMA DIAGNOSTICS Silver Stain HT-100 was much easier to use for rating CA concentration in disease sites. This test was applied to subgingival plaque smears from 28 periodontal disease sites of 22 HIV-seronegative patients and 45 sites of 12 HIV-seropositive patients. After staining, the smears were examined and scored (Davenport Index). None of the 12 HIVseropositive patients but 15 of the 22 HIV-seronegative patients had a score of zero at all sites. The score ranged from 0 (no CA) to 3 (large numbers of CA in all fields). In the seropositive patients the median score was 2 while in the seronegative group it was 0.The much higher scores obtained in specimens from periodontal disease sites of the AIDS patients suggest that this simple rapid test might be valuable for screening individuals and indicating those requiring further testing or monitoring for AIDS.
Image Analysis Method to Count Silver-Stained Candida in Aids Patients' Subgingival Plaques
Authors: Hanker Jacob S. , Patel Hinesh B. , Giammara Beverly L. , Von Der Heiden Juergen 
Published: March 2011

ABSTRACTComputer-assisted microscopic image analysis of silverstained subgingival plaque smears was shown to be far more dependable and reproducible than subjective scoring or rating by visual inspection to estimate the amounts of Candida 4ibicans(CA) present. High CA counts in subgingival plaques from atypical periodontal diseased sites could suggest that an individual be tested or monitored further for AIDS. This is especially the case if the individual is in a high risk group or if the CA count cannot be ascribed to immunosuppression resulting from diabetes, corticosteroid or broad-spectrum antibiotic therapy, cancer chemotherapy or blood transfusion for hemophilia. In many such situations this simple, rapid procedure may be useful in screening for AIDS when serologic procedures for the HIV virus may be equivocal.
Processing of Polymers and Polymer Composites In a Microwave Applicator
Authors: Hawley Martin C. , Wei Jianghua 
Published: March 2011

ABSTRACTPolymers and polymer composites have been processed In a cylindrical resonant microwave applicator at a frequency of 2.45GHz. Stoichlometric mixtures of two epoxy/amine systems, DGEBA (Diglycidyl Ether of Bisphenol A)/DDS (4,4'-Diaminodiphenyl Sulfone) and DGEBA/mPDA(m-Phenylene Diamine), were microwave and thermally cured Isothermally using a thin film technique. FTIR was used to determine the extent of cure. Increased reaction rates were observed In microwave cure when compared to those of thermal cure. The rate Increase due to microwave effects was much greater for the DGEBA/DDS system than for DGEBA/mPDA. Also, crossply and unidirectional 24-ply and 72-ply graphite/epoxy laminates(AS4/3501-6 prepreg, Hercules Corp.). were processed using microwave radiation. The flexural properties of the microwave processed composites were strongly dependent on the resonant heating mode. Comparable flexural properties were obtained for the unpressurized microwave processed composites and the pressurized autoclave processed composites. Proper controlled-hybrid modes are required to process composites of high mechanical properties. The procedures for obtaining these controlled-hybrid modes are described.
Electromagnetic Processing of Polymers: I. Basic Concepts and Molecular Design of The Macromolecules
Authors: Hedrick J. C. , Lewis D. A. , Ward T. C. , Mcgrath J. E. 
Published: March 2011

ABSTRACTMicrowave processing has been utilized to process thermosetting polymeric materials. Specifically, fundamental studies relating epoxy network generation to processing conditions have been investigated in a tunable cylindrical cavity operating at a frequency of 2.45 GHz. These studies demonstrate that fully cured networks can be generated in ten minutes with the retention of good mechanical properties. Furthermore, toughened epoxy systems which utilize carefully designed amine terminated poly(arylene ether sulfone) thermoplastics as reactive oligomers have resulted in novel phase separated morphologies. In fact, it has been demonstrated that the morphology in these multiphase systems can actually be controlled by utilizing microwave processing. Bismaleimide toughened systems, devised by similar strategies, have demonstrated a 10–20 fold reduction in the time required to achieve full cure.
Microwave Enhancement of Chemical and Physical Reactions
Authors: Fanslow Glenn E. 
Published: March 2011

ABSTRACTExamples of the effects of microwave processing are presented that suggest that microwave ‘heating’ creates higher excitation levels and increased chemical and physical reactions within a material than would be expected if the only change that had been produced by the microwaves was a rise in temperature. The examples include a chemical coal-cleaning process. the destruction of coronene in alcohol, heating of high-temperature superconducting compounds. and a microwaveinduced photovoltaic effect.
Electromagnetic Processing of Polymers: II. Quantitative Investigations of Microwave Processed Thermoplastics (Microwave Calorimetry)
Authors: Chen M. , Zumbrum M. A. , Hedrick J. C. , Mcgrath J. E. , Ward T. C. 
Published: March 2011

ABSTRACTThe microwave heatability of various thermoplastic polymers was investigated. The concept of microwave calorimetry was proposed to quantitatively illustrate how viscoelastic behavior controlled microwave heatability. Specifically, heating rate as a function of sample temperature revealed a distinct maximum which was identified as the Tg at 2.45 GHz. The critical temperature, Tc, necessary for rapid microwave heating was identified by drawing a tangent to the heating rate curve and extrapolating to a critical value at zero heating rate. In separate experiments, low frequency (100 kHz) dielectric measurements were made which show the frequency dependence of Tg by means of Arrhenius activation energy plots. In general, the larger the activation energy, the closer the critical heating temperature, TC, was to the Tg determined by DSC. The smaller the activation energy, the further dielectric loss shifted with increased frequency so that Tc was very far from Tg determined by DSC.
Dielectric Properties Measurements and Data
Authors: Carpenter Joseph A. 
Published: March 2011

ABSTRACTThis paper reviews measurement techniques and sources of data for the dielectric constant and loss factor of solid materials. Accurate values of such properties are basic to intelligent design of materials processing schemes utilizing electromagnetic energy. Emphasis is on techniques and data for these properties in the “microwave” range of frequencies of roughly 108 to 1011 Hz and at elevated temperatures.
Microwave Materials Dielectric Measurements
Authors: Purinton Don , Stiborek Leon 
Published: March 2011

ABSTRACTTexas Instruments Defense Systems and Electronics Group develops radars, missile systems, infra-red systems and electronic systems for the Defense Department. Materials having special microwave properties are needed for radar systems, missile systems that home on microwave emissions, microwave emitter locator systems, and jamming systems. The microwave materials appear in the form of antennas, lenses, radomes, windows, dielectric loading materials, potting materials, dielectric transmission lines, microwave absorbing materials, adhesives, sealants, coatings, and foams. Naturally, the complex permittivity and permeability of these materials need to be known to enhance their application and control their properties in manufacturing. Texas Instruments has a microwave materials test laboratory that includes permittivity and permeability measurements as well as physical and thermal properties. The samples come in many different forms, measurement at different frequencies are needed and the electrical properties cover a wide span (conductors to dielectrics and foams to ferrites). For this reason, many different methods of dielectric and magnetic measurement are used. These various methods will be discussed below.
Microwave Dielectric Properties of Elastomers Containing Particulate Metal Fillers
Authors: Helme Barry G.M. 
Published: March 2011

ABSTRACTElastomers have been manufactured containing varying concentrations of particles of Ag/Al, Ag/Cu, Ag/Ni, Ag/glass (G3), Ni/graphite, Ni, and Ag. Their dielectric and microwave properties have been measured between 0.4 GHz and 40 GHz and at temperatures between ambient and 100°C. The filler particles are small relative to the microwave wavelength but larger than the skin depth. Sheets of these elastomers of up to 2 mm thickness gave been subjected to cyclical stretching of up to 40% elongation and up to 10° cycles. The microwave properties have been measured as a function of numbers of stretching cycles and composition of elastomer. Some correlations were found between the composition, the microwave properties and the number of stretch cycles completed.It was found in general that repeated stretching degraded the initially high conductivity of the loaded elastomers. This effect was also revealed by the increase in microwave transmissivity through the sheets, and a decrease in reflectivity. Formulations of elastomer-metal particle mix have recently been produced which have a microwave transmissivity more Phan 80 dB below the incident signal, for a 2 mm thick sample, even after 106 stretching cycles of 20% elongation. This property is of great value for the use of the elastomer as a reflective microwave shield.
Microwave Resonator Techniques for Sorting Dielectric Objects
Authors: Kraszewski Andrzej W. , Nelson Stuart O. 
Published: March 2011

ABSTRACTMicrowave resonators have been found to be sensitive devices for sorting dielectric objects of irregular shapes according to their volumes, for detecting voids inside objects of similar shape or for determining moisture content in objects of varying volumes. Fundamental principles of operation as well as experimental results are discussed in the paper.
Patterning of Microwave Plasma Deposited Diamond Films
Authors: Leksono Moeljanto W. , Shanks Howard R. 
Published: March 2011

ABSTRACTPatterning has been successfully performed on diamond films deposited on polished silicon wafers from CH4 and H2 gases using microwave plasma chemical vapor deposition. The selectivity was achieved using a lift off process on silicon wafers which had been polished with diamond paste. The lift off process involves deposition and patterning of a thin ZnO film followed by deposition of amorphous silicon using a glow discharge technique. This is followed by microwave plasma CVD of the diamond film. The film is deposited selectively on the crystalline silicon areas of the substrate. Quality and patterning resolution of the resulting diamond films have been determined.
First Results of In-Can Microwave Processing Experiments for Radioactive Liquid Wastes at the Oak Ridge National Laboratory
Authors: White T. L. , Youngblood E. L. , Berry J. B. , Mattus A. J. 
Published: March 2011

ABSTRACTThe Oak Ridge National Laboratory (ORNL) Waste Handling and Packaging Plant is developing a microwave process to reduce and solidify remote-handled transuranic (RH-TRU) liquids and sludges presently stored in large tanks at ORNL. Testing has recently begun on an in-drum microwave process using nonradioactive RH-TRU surrogates. The microwave process development effort has focused on an in-drum process to dry the RH-TRU liquids and sludges in the final storage container and then melt the salt residues to form a solid monolith. A 1/3-scale proprietary microwave applicator was designed, fabricated, and tested to demonstrate the essential features of the microwave design and to provide input into the design of the fullscale applicator. Conductivity cell measurements suggest that the microwave energy heats near the surface of the surrogate over a wide range of temperatures. The final wasteform meets the waste acceptance criteria for the Waste Isolation Pilot Plant, a federal repository for defense transuranic wastes near Carlsbad, New Mexico.
Application of Gyrotron Radiation for Coating and Welding
Authors: Paton B. E. , Sklyarevich V. E. 
Published: March 2011

ABSTRACTThe availability of high power high frequency microwave sources of up to tens of kW has opened up important technological and industrial applications of microwave radiation. The particular use of gyrotrons for generating the high power microwaves is considered.The application of high power microwaves for fusing wear resistant coatings onto refractory materials is discussed, together with the brazing of ceramics, welding together of thick metal parts and the rapid heating and curing of polymers for high reliability long life environmental coatings.It is shown that the use of high power gyrotron radiation enables considerable improvements to be made on conventional technologies for high temperature processing of materials and enables the development of new and efficient processes.
Synthesis of Ultrafine, Multicomponent Particles Using Phospholipid Vesicles
Authors: Liu H. , Graff G. L. , Hyde M. , Sarikaya M. , Aksay I. A. 
Published: March 2011

AbstractBecause of their unique properties of self-assembly and selective ion permeability across the lipid bilayers, phospholipid vesicles were used as reaction vessels for the synthesis of ultrafine, multicomponent ceramic particles containing Y, Ba, Cu, and Ag. Chemical inhomogeneities in the system were limited to the individual particle size (< 50 nun), which was a considerable improvement over particles prepared using bulk precipitation routes. The consistent barium deficiency was a serious problem that arose when attempting to control the stoichiometry of the multicomponent system. Our experimental evidence suggests that chemical interactions between the barium cations and the vesicleforming phospholipid may inhibit the precipitation of barium salts. In a parallel study, we performed consolidation studies on vesicle-precipitated Ag2O particles before and after the removal of the phospholipid molecules. Particle packing was greatly improved in the surfactant coated particles. This demonstrates the multifunctionality of this biomimetic system in which the vesicle membrane simultaneously acts as: (i) a reaction cell for particle precipitation, (ii) an ion selective membrane that affects precipitation kinetics, (iii) a barrier to prevent spontaneous agglomeration of the ultrafine particles, and (iv) a lubricant/dispersantth atfacilitatesp article rearrangementd uring consolidation.
Wavelength Dependence of the Photorefractive and Photodiffractive Properties of Holographic Thin Films Based on Bacteriorhodopsin
Authors: Birge Robert R. , Izgi K. Can , Stuart Jeffrey A. , Tallent Jack R. 
Published: March 2011

AbstractThe photorefractive and photodiffractive properties of a 2 × 10−3 M, 30μim thin film of bacteriorhodopsin at - 40°C are analyzed by using optical absorption spectroscopy, the Kramers- Kronig transformation and coupled wave theory. Conversion of M to bR generates a dispersion in the refractive index that has a broad negative band from 450 to 540 nm [Δn500nm - -0.0016] and a broad positive band from 590 to 700 nm [Δn605nm - 0.0016]. The large change in refractive index for moderate solute concentration is due to the formation of the protonated Schiff base chromophore in bR which generates a large red shift in the absorption spectrum as well as a large increase in oscillator strength. The integrated diffraction efficiency from 300 - 800nm is dominated by refractive index contributions (ηphase) which are maximum in regions of minimal bR and M absorption. The maximum in the refractive (phase) component occurs at 451 nm (ηphase - 9.7%) whereas the maximum in the absorption component occurs at 575 nm (ηabs - 2.2%). The maximum efficiency of diffraction is observed at ∼440 nm (ηtotal - 10.7%). Adequate diffractive performance for most applications is predicted for write wavelengths in the regions 380 - 420 & 500 - 650 nm and for read wavelengths from 380 to 740 nm.
Novel Polymer Synthesis using Enzymatic Catalysis in Nonaqueous Media
Authors: Dordick Jonathan S. , Patil Damodar. R. , Ryu Keungarp , Rethwisch David G. 
Published: March 2011

AbstractThe use of enzymes in organic solvents has enabled two distinct polymer syntheses to be performed. The first is the enzyme-catalyzed polycondensation of sucrose with an adipic acid derivative in pyridine. Taking advantage of the extremely high regioselectivity of proleather, an alkaline protease, sucrose has been polymerized with 6 and 1' ester linkages. The result is a highly water-soluble product with sucrose an integral part of the polymer backbone. The polyester is degraded by the proleather in aqueous solution, thereby suggesting that the polymer is biodegradable. The second polymer synthesis is the free-radical polymerization of phenols using horseradish peroxidase in dioxane-water mixtures. Molecular weights in excess of 25,000 have been produced. The scope of polymerization can be predicted based on enzyme kinetics in organic media and using a Monte Carlo simulation. Astonishingly accurate simulations have been run that suggest that the high degree of control afforded by enzymatic catalysis over conventional chemical catalysts can be usedpredictively in polymer synthesis. This is of great importance in process control of polymer syntheses.
Transient Potentials Transmitted by an Artificial Electrochemical Synapse
Authors: Triffet T. , Calvert P. , Huntoon T. W. 
Published: March 2011

AbstractExperiments have been made with a simple device consisting of two asymmetrically insulated electrodes separated by a thin electrolytic layer. This device has been found to exhibit a wide variety of transient potentials similar to those transmitted by biological synapses, thus suggesting the possibility of constructing a network of similar devices which simulates the behaviour of a biological neural network.
The Avian Eggshell as a Model of Biomineralization
Authors: Arias Jose L. , Fernandez Maria S. , Laraia Vincent J. , Janicki Jaroslaw , Heuer Arthur H. , Caplan Arnold I. 
Published: March 2011

AbstractThe avian eggshell is one of the most rapidly mineralizing biological systems known. By understandi'ng the key components and steps in this process, we hope to provide relevant information for fabrication of ceramic composites. The calcification of the eggshell occurs in three main steps: 1) fabrication of an organic matrix, 2) nucleation of an inorganic phase on the organic matrix, and 3) space-filling growth of the calcite phase. The different layers of an eggshell can be separately isolated and studied. Three approaches have been used in our study of the eggshell: 1) characterization of the organization and chemical composition of the shell, 2) selective removal or blocking of particular components to improve the remineralization of demineralized shells, and 3) addition of new components to produce composite ceramics of different kinds. In this preliminary communication, the organization of the shell matrix and membranes and their association with the crystal phase, the immunohistochemical occurrence and distribution of types I and X collagen, and of different proteoglycans are reviewed. Also the preliminary findings of the remineralization of the intact or modified eggshell are presented. These experiments allow us to identify the essential steps in forming a natural composite ceramic.
Growth of TiO2 Particles within a Polymeric Matrix
Authors: Burdon J. W. , Calvert Paul 
Published: March 2011

AbstractAs a simple model for biomineralization we are investigating the deposition of oxide particles into polymers by the in situ hydrolysis of oxides. By light scattering and electron microscopy we have observed the development of titania in polyvinylchloride. Hydrolysis is due to exposure to atmospheric moisture after film formation under very dry conditions. We believe of alkoxide initially phase separate and then are hydrolysed. Using a strongly Aolymer as a matrix for silica formation we present evidence for catalysis of particle -tby the matrix.
Mechanics of Natural Composites
Authors: Saliba Joseph E. , Schiavone Rebecca C. , Gunderson Stephen L. , Taylor Denise G. 
Published: March 2011

AbstractThis study was initiated to investigate the structural response of the bessbeetle to determine potential advantageous ramifications and effects on the optimization of synthetic composite materials. The result of the micromechanics sensitivity study of various parameters are presented. Variables such as fiber size and shape, fiber volume fraction, ratio of modulus of elasticity of fiber over matrix, are changed one variable at a time, and the response quantities such as stress and tranverse modulus are presented.
Decolorization of Chitosan
Authors: Allan G. Graham , Muvundamina Mutombo 
Published: March 2011

AbstractThe industrial process for extracting chitosan from low cost shellfish waste is well known. It comprises three basic steps: deproteinization, demineralization of the shells to yield chitin, followed by deacetylation of chitin to produce chitosan. However, the product obtained from the process often still contains many impurities. In general, these encompass minerals and carotenoids bonded to chitosan. The treatment of chitosan flakes with aqueous solutions of inorganic polybasic acids permits the removal of the impurities mentioned above. This paper describes an engineering-type procedure which develops a pure, colorless material having a controlled molecular weight.