Unique phospholipid metabolism in mouse heart in response to dietary docosahexaenoic or α-linolenic acids

Diet and fatty acid metabolism interact in yet unknown ways to modulate membrane fatty acid composition and certain cellular functions. For example, dietary precursors or metabolic products of n-3 fatty acid metabolism differ in their ability to modify specific membrane components. In the present study, the effect of dietary 22∶6n−3 or its metabolic precursor, 18∶3n−3, on the selective accumulation of 22∶6n−3 by heart was investigated. The mass and fatty acid compositions of individual phospholipids (PL) in heart and liver were quantified in mice fed either 22∶6n−3 (from crocodile oil) or 18∶3n−3 (from soybean oil) for 13 wk. This study was conducted to determine if the selective accumulation of 22∶6n−3 in heart was due to the incorporation of 22∶6n−3 into cardiolipin (CL), a PL most prevalent in heart and known to accumulate 22∶6n−3. Although heart was significantly enriched with 22∶6n−3 relative to liver, the accumulation of 22∶6n−3 by CL in heart could not quantitatively account for this difference. CL from heart did accumulate 22∶6n−3, but only in mice fed preformed 22∶6n−3. Diets rich in non-22∶6n−3 fatty acids result in a fatty acid composition of phosphatidylcholine (PC) in heart that is unusually enriched with 22∶6n−3. In this study, the mass of PC in heart was positively correlated with the enrichment of 22∶6n−3 into PC. The increased mass of PC was coincident with a decrease in the mass of phosphatidylethanolamine, suggesting that 22∶6n−3 induced PC synthesis by increasing phosphatidylethanolamine-N-methyltransferase activity in the heart.     

萧条的1992年促使轮胎生产者调整

萧条的１９９２年促使轮胎生产者调整ＢｒｕｃｅＤａｖｉｓ著曾泽新译吴秀兰校预期１９９２年的经济复苏并未实现，恢复的进程拖得比预期的更长。结果，大多数轮胎生产者被迫再次采取保守的经营，裁减人员，让股东对利润降低，甚至亏损作好思想准备。据报道，在大轮胎公司...     

Summarizing high-level scene behavior

We present several novel techniques to summarize the high-level behavior in surveillance video. Our proposed methods can employ either optical flow or trajectories as input, and incorporate spatial and temporal information together, which improve upon existing approaches for summarization. To begin, we extract common pathway regions by performing graph-based clustering on similarity matrices describing the relationships between location/orientation states. We then employ the activities along the pathway regions to extract the aggregate behavioral patterns throughout scenes. We show how our summarization methods can be applied to detect anomalies, retrieve video clips of interest, and generate adaptive-speed summary videos. We examine our approaches on multiple complex urban scenes and present experimental results.     

The technology of halogen-free flame retardant phosphorus additives for polymeric systems

Halogen-free flame retardant additives based on phosphorus function by developing a protective char. A variety of additives are available, ranging from the element itself, in the form of amorphous red phosphorus, to specialty organophosphorus compounds, and examples of their use in a range of thermoplastics are given. Intumescent formulations based on phosphates are especially designed for polyolefins. The behavior of a typical intumescent system is described with respect to flame retardant performance, thermal stability, water sensitivity, and filler compatibility.     

Coating evaluation and validation of accelerated test conditions using an in-situ corrosion sensor

An in-situ corrosion sensor was used to obtain electrochemical impedance spectroscopy (EIS) measurements on coated panels under a variety of accelerated laboratory test conditions as well as ambient exposure at a Florida beach. Three studies are reported. The first compared the sensor (EIS) measurements taken in a salt fog chamber to those obtained using a clamp-on cell and the conventional remote electrode/immersion approach. For coatings with minimal edge defects, the two methods gave equivalent results. For coatings with edge defects, the sensor was able to detect the defects provided the surface was wet, as in the salt fog chamber. In contrast, the conventional approach was unable to detect defects unless they were within the confines of the clamp-on cell. In the second case, sensor measurements were used to compare coating degradation during salt fog, a cyclic corrosion test, humidity, and immersion to that occurring at a Florida beach. The cyclic corrosion test showed an excellent correlation with beach exposure while the salt fog and other test showed very little correlation, suggesting that the cyclic test is more valid for discriminating coating performance for seacoast exposure. The sensor also indicated that the test could be short-ened by up to 40% without significantly reducing the validity of the test. In the final example, a series of primers and appliqués were evaluated using the cyclic corrosion test. The sensor EIS results allowed a discrimination between the materials sets even though there was little or no visual difference between the specimens. 10260 Old Columbia Rd., Columbia, MD 21046.     

The removal of radioactive caesium contaminants from simple aqueous solutions

Cs ions can be removed from aqueous solutions by forming a precipitate of copper ferrocyanide which, having occluded the Cs ions, can in turn be floated by means of an anionic collector. Collection was achieved with either α-sulphopalmitic acid or sodium dodecyl sulphate depending on what interfering ions were initially present in the solution. Recoveries of 98–99% were obtained on batch scale experiments and 97.5–98.5% on continuous scale operation. The investigations of the flotation parameters of pH, gas-rate, concentrations of precipitating reagents and collector, as well as the interference effects of other ions are discussed. Using data obtained in batch scale tests, continuous scale experiments were designed and operated.     

A MECHANISTICALLY BASED MATHEMATICAL MODEL OF SULFUR DIOXIDE ABSORPTION INTO A CALCIUM HYDROXIDE SLURRY IN A SPRAY DRYER

A mathematical model has been developed to predict So₂ absorption and removal during the constant rate drying period of a spray dryer. The model, based on film theory, treats the atomized slurry droplets as spheres containing discrete sorbent particles of slaked lime with the fluid uniformly distributed around the individual particles. The model includes gas and liquid phase mass transfer coefficients as well as resistance to Ca(OH)₂ dissolution. A sensitivity analysis has been conducted and a comparison was made between pilot-scale experimental data and model-predicted values of S0₂ removal efficiency.     

Particle size analysis by automatic siever

Automation of the wet sieving process in an instrument for particle size analysis is described. A powder is consecutively subjected to three sieves of any selected meshes from 38 μm up and the resulting fractions are collected individually, including both the undersize and oversize, in a submerged filter. The initial filter weight and the weights of all collected fractions are determined separately and stored in the microcomputer memory. Upon completion of an analysis, the sieved fraction weights are recalled, the total sample weight is calculated, and results are presented as weight per cent. Completion of each sieving step is established by filter weight constancy according to prearranged programming. Upon completion of an analysis, the system backwashes the filter and re-establishes conditions for the next analysis. Tests for accuracy with a standard material and repeated testing for short and long-term reproducibility are included. Applicability to a variety of powders is demonstrated.     

EVAPORATION FROM POROUS MEDIA: A CAPILLARY MODEL OF A PENETRATING FRONT

A capillary tube model was solved to investigate the influence of mass transfer coefficient, temperature, and front depth on the evaporation rate during the penetrating-front period of water-filled porous media dried in hot air. The results show that increasing the flow rate of the drying air is not so efficient as increasing the sample temperature. Due to attenuating diffusion rate, the rate of liquid front migration decreases with time. The calculations explain the falling rate period behavior of sandstone heated at 121°C. Trends depicted by the model may be useful for the design of heating conditions for drying processes.     

Fiber Coating Concepts for Brittle-Matrix Composites

The current interest in tough, high-temperature materials has motivated fiber coating development for brittle-matrix composites with brittle reinforcements. Such coatings are needed for controlled interface debonding and frictional sliding. The system investigated in this study was sapphire fiber-reinforced alumina. This system is thermochemically stable for severe use conditions, exhibits little thermal expansion mismatch, and utilizes the excellent strength and creep resistance of sapphire reinforcements. Porous oxide and refractory metal coatings which satisfy requirements for toughness improvement in these composites were identified by employing a variety of newly developed mechanical testing techniques for determining the interfacial fracture energies and sliding resistances.