Polymorphic Data Modeling

There are currently no data modeling standards for modeling NoSQL document store databases. This work proposes a standard to fill the void. The proposed standard is based on our new data modeling pattern named The Polymorphic Table Pattern. The pattern embraces the “schemaless” nature of document store NoSQL while allowing the data modeler to use his or her existing skillsets. The concepts of our proposed modeling have been demonstrated against MongoDB

Promoting HIV/AIDS Prevention through Soap Operas: Tanzania’s Experience with Maisha

In the past three decades television soap operas have been used as a means of healtheducation and persuasion. In recent years, the proliferation of entertainment televisionworldwide has made the soap opera a powerful source of educational and social messages.One of the most critical global health issues of today is the need to reduce HIV/AIDSinfection, particularly on the continent of Africa. In the 1990s, the country of Tanzaniabroadcast a highly effective radio soap opera to promote HIV/AIDS prevention. In 2000,Tanzania again employed the use of the soap opera to address HIV/AIDS as well as othersocial issues, this time through television. Our research indicates that the Tanzaniantelevision soap opera employed in this effort, Maisha, effectively promoted HIV/AIDSprevention among television viewers. In particular, those who were more involved withMashaka, the star of Maisha, were more powerfully influenced by the health messagescommunicated through the programme. The implications of this research for usingentertainment for HIV/AIDS prevention are discusse

AGGREGATE DATA MODELING STYLE

The paper presents our progress in defining an aggregate data modeling style using new operators with the standard data modeling language Idef1X. By defining a style, using an established notation, the proposed allows reuse of existing data modeling expertize. The style is intended to support data modeling for so called aggregate-oriented NoSQL databases

Spectrophotomatic Assay for the Enzyme Catalyzed Reaction of 4-nitroquinoline 1-oxide with Glutathione

4-Nitroquinoline 1-oxide (4NQO(is a toxic and carcinogenic compound that has been reported to be subject to conjugation with glutathione (GSH). This reaction may proceed non-enzymatically or be catalyzed by GSH transferases. The non-enzymatic rate for this reaction has been reported to be very high. The purposes of this investigation were to develop a spectrophotometric assay for the reaction of4NQO with GSH and to determine whether the rate for the enzyme catalyzed reaction was significant relative to the non-enzymatic reaction. The absorbance spectrum of 4NQO in phosphate buffer exhibited a maximum at 365 nm. Reaction of 4NQO with GSH was accompanied by a shift to 353 nm and an absorbance increase which was maximal at 350 nm. The formation of product could be quantitated from the increase in absorbance at 350 nm, where the change in the millimolar extinction coefficient was 7.20 mM^-1 cm^-1. Although the non-enzymatic reaction of 4NQO and GSH proceeded rapidly at or above pH 8, at physiological pH this reaction was largely enzyme dependent. In an assay system containing 0.1 mM 4NQO, 1 mM GSH, and 0.1 M potassium phosphate, at 25°C, the conjugation of 4NQO with GSH by mouse livercytosol was optimal at pH 6.5 - 7.5. At pH 6.5 and 1 mM GSH, a GSH transferase purified from mouse liver catalyzed the reaction of 4NQO with GSH with a maximum velocity of 156 μmoles/min per mg of protein. The Km for 4NQO was 35 μM. The high activity of liver cytosol in promoting the reaction of 4NQO with GSH and the high affinity of the purified GSH transferase for 4NQO suggest that enzymatic catalysis of this reaction may be of considerable significance in vivo

NEXT Ion Propulsion System Configurations and Performance for Saturn System Exploration

The successes of the Cassini/Huygens mission have heightened interest to return to the Saturn system with focused robotic missions. The desire for a sustained presence at Titan, through a dedicated orbiter and in-situ vehicle, either a lander or aerobot, has resulted in definition of a Titan Explorer flagship mission as a high priority in the Solar System Exploration Roadmap. The discovery of active water vapor plumes erupting from the tiger stripes on the moon Enceladus has drawn the attention of the space science community. The NASA's Evolutionary Xenon Thruster (NEXT) ion propulsion system is well suited to future missions to the Saturn system. NEXT is used within the inner solar system, in combination with a Venus or Earth gravity assist, to establish a fast transfer to the Saturn system. The NEXT system elements are accommodated in a separable Solar Electric Propulsion (SEP) module, or are integrated into the main spacecraft bus, depending on the mission architecture and performance requirements. This paper defines a range of NEXT system configurations, from two to four thrusters, and the Saturn system performance capability provided. Delivered mass is assessed parametrically over total trip time to Saturn. Launch vehicle options, gravity assist options, and input power level are addressed to determine performance sensitivities. A simple two-thruster NEXT system, launched on an Atlas 551, can deliver a spacecraft mass of over 2400 kg on a transfer to Saturn. Similarly, a four-thruster system, launched on a Delta 4050 Heavy, delivers more than 4000 kg spacecraft mass. A SEP module conceptual design, for a two thruster string, 17 kW solar array, configuration is characterized

Interaction of Sodium, Sulfur, and Silica during Coal Combustion

The Interaction of Sodium, Sulfur, and Silica at Conditions Typical in a Pulverized Coal Furnace Was Investigated by using Both Model Mixtures and a Synthetic Coal. the Model Mixtures Consisted of Selected Inorganic Constituents that Were Well Mixed in Proportions Typically Found in Low-Rank Coal. the Synthetic Coal Consisted of a Furfuryl Alcohol Polymer with Appropriate Amounts of Sodium, Sulfur, and Silica to Duplicate the Characteristics of Low-Rank Coal. the Model Mixtures and Synthetic Coal Were Burned in a Laminar Flow (Drop-Tube) Furnace at 900, 1100, 1300, and 1500 °C and Residence Times of 0.1,0.5,1.5, and 2.4 S. the Resulting Char and Fly Ash Particles Were Quickly Quenched, Collected, and Analyzed with a Scanning Electron Microscope (SEM) to Determine Size and Composition. Results Indicated that the Formation of Sodium Silicates is Favored by Higher Temperatures and Longer Residence Times. Thermodynamic Calculations and the Model Mixture Studies Indicated above 1100 °C There is Little Interference in the Formation of Sodium Silicates by Sodium Sulfates. in the Synthetic Coal Studies, Sodium Sulfate Particles Were Detected on the Surface of the Larger Sodium Silicate Fly Ash Particles Formed at Lower Temperatures. the Size and Prevalence of the Sodium Sulfate Particles Decreased as Temperature Was Increased. Fly Ash Particle Formation Was Characterized by Fragmentation Followed by Coalescence. Fragmentation Was More Prevalent at Higher Temperatures and Smaller Fly Ash Particles Were Formed. Larger Particles Were Formed at Lower Temperatures, Indicating More Complete Coalescence with Some Cenosphere Formation. © 1991, American Chemical Society. All Rights Reserved