Suspension Processing of Al2O3/SiC Whisker Composites

Homogeneous Al₂O₃ powder/SiC whisker compacts were prepared by suspension processing. By optimizing the conditions for particle/whisker codispersion, castable suspensions could be prepared at total-solids concentrations 50 vol%. Green bodies with high relative density (∼66% to 70%) were obtained with SiC whisker contents in the range of 5 to 30 vol%. Although densification was severely inhibited by the SiC whiskers, significantly higher sintered densities were obtained by suspension processing compared to dry processing.     

Imaging applications of synchrotron X-ray phase-contrast microtomography in biological morphology and biomaterials science. I. General aspects of the technique and its advantages in the analysis of millimetre-sized arthropod structure

Synchrotron‐generated X‐rays provide scientists with a multitude of investigative techniques well suited for the analysis of the composition and structure of all types of materials and specimens. Here, we describe the properties of synchrotron‐generated X‐rays and the advantages that they provide for qualitative morphological research of millimetre‐sized biological organisms and biomaterials. Case studies of the anatomy of insect heads, of whole microarthropods and of the three‐dimensional reconstruction of the cuticular tendons of jumping beetles, all performed at the beamline ID19 of the European Synchrotron Radiation Facility (ESRF), are presented to illustrate the techniques of phase‐contrast tomography available for anatomical and structural investigations. Various sample preparation techniques are described and compared and experimental settings that we have found to be particularly successful are given. On comparing the strengths and weaknesses of the technique with traditional histological thin sectioning, we conclude that synchrotron radiation microtomography has a great potential in biological microanatomy.     

Tectonic Gardens

The Tectonic Gardens initiative focuses on small, unremarkable, and often forgotten places adjacent to the lives of underserved people. Located in the boundary between architecture and landscape, these projects seek to create experiential delight out of small-scale design opportunities. Through the adaptive reuse and recycling of leftover urban space, Tectonic Gardens augment and enhance existing building infrastructures with new, primarily outdoor spaces that provide pragmatic functions, promote play, and exhibit a social and environmental conscience.     

Achieving Incremental Compilation through Fine-grained Builds

Traditional programming environments represent program source code as a set of source files. These files have various ‘dependencies’ on each other, such that a file needs recompilation if it depends on a file which has changed. A ‘build tool’ is used to process these dependencies and bring the application ‘up-to-date’. An example of a build tool is the UNIX ‘make’. This paper examines what happens when the dependencies used by the build tool are expressed between functions (or objects) rather than between files. Qualitative differences arise from the difference in granularity. The result is an effective incremental compilation programming environment, based on the C++ language. It is called ‘Barbados’, and is fully implemented. The environment resembles an interpreter in that changes to source code appear to be immediately reflected in all object code, except that errors are reported early as in compiled systems. Incremental compilation is not a well-used technology, possibly because the ‘fine-grain build’ problem is not well understood. Nevertheless, incremental compilation systems do exist. The advantages of the system described here are that it works with relatively standard compilation technology, it works for the C++ language including the preprocessor, it is an elegant solution and it is more efficient than competing algorithms. © 1997 by John Wiley & Sons, Ltd.     

Knowledge-based scheduling in flexible manufacturing systems: An integration of pattern-directed inference and heuristic search

This paper presents a knowledge-based scheduling approach based on the problem-solving techniques developed in artificial intelligence. The approach is based on three key techniques. The first is the pattern-directed inference technique to capture the dynamic nature of the scheduling environment. The second is the non-linear planning technique to coordinate manufacturing processes and resource assignments. The third technique is the A? search algorithm to expedite the searching procedure. It models the scheduling process by state-space transitions; the job routing is obtained through selecting a sequence of scheduling operators guided by heuristics. Keeping track of the manufacturing system by a symbolic world model, this approach is adaptive to such environmental changes as new job arrivals and machine breakdowns, suitable for making real-time scheduling decisions.     

TISSUE DISTRIBUTION AND METABOLISM OF AFLATOXIN B1-14C IN LAYER CHICKENS

The effects of administering low levels of aflatoxin B₁-¹⁴C by crop intubation daily for 14 days to layer chickens were determined. Studies on the distribution of ¹⁴C in the blood, selected organs, tissues, eggs and excreta were conducted. No toxic effects were observed in layer chickens during the course of the experiment. The layer chickens excreted 92.15% of the ¹⁴C administered. Of the ¹⁴C retained, 19.5, 16.1, 3.9, 7.2, 26.4 and 26.9% were detected in the blood, liver, heart, gizzard, breast and leg, respectively. No radioactivity was detected in egg samples collected. Chemical assay of those samples demonstrating radioactivity revealed that 81.2% of the radioactivity in these substrates was soluble in aqueous extracts while approximately 10% was ex tractable by classical extraction procedures. Treatment of the aqueous extracts for conjugated steroids by treatment with Beta-glucuronidase revealed that 31.5% of the ¹⁴C detected in the aqueous extract was a liberated glucuronide conjugate of aflatoxin M₁−¹⁴C     

FREQUENCY OF SALMONELLA, CAMPYLOBACTER, LISTERIA AND ENTEROBACTERIACEAE DETECTION IN COMMERCIALLY COOL WATER-WASHED SHELL EGGS

The effect of cool water washing on shell egg temperature and pathogen detection was examined. Three temperature schemes were utilized in commercial dual washer systems: (1) HH = 48.9C, 48.9C; (2) HC = 48.9C, 23.9C; and (3) CC = 23.9C, 23.9C. HH eggsmaintainedthe highest surface temperature (26.25C in‐line, 20.25C off‐line and 23.25C combined, P < 0.05). The lowest temperatures were found in the CC eggs (21.25C in‐line, 17.25C off‐line and 19.25C combined). The frequency of Enterobacteriaceae detection in shell and membrane emulsions was greatest for the CC eggs (P < 0.05 for in‐line and combined). There was no difference in Enterobacteriaceae detection for the off‐line facility. Salmonella was detected in three of 384 samples from the in‐line facility. They were found in HC (2) and CC (1) shell emulsions. Two of 384 samples were positive for Campylobacter from the in‐line facility (CC). Three wash water samples were positive for Listeria in the off‐line facility (1 HC, 2 CC). No pathogens were detected in the egg contents during this study. The results of this study indicate that warm followed by cool water washing has the potential of decreasing egg temperature while maintaining surface microbiology at an acceptable level.     

Analysis of the anthocyanin composition of Cabernet Sauvignon and Portugieser wines provides an objective assessment of the grape varieties

This paper presents data on the ratios of acetylated to p -coumaroylated anthocyanins of authentic and unadulterated trade samples of 71 Cabernet Sauvignon and 40 Portugieser winegrape varieties. The relative peak areas of nine characterising anthocyanins were determined by a standardised and validated HPLC-method. The 95%-confidence ranges calculated from the data ranged from 2.9 to 5.7 for the Cabernet Sauvignon wines and from 0.7 to 1.7 for the Portugieser wines. The rule that individual anthocyanin components are normally distributed was also confirmed for wines vinified from Gamay and Kadarka (Gamza) grape varieties.     

EFFECTS OF DARK STORAGE TIME AND UV-FILTERED FLUORESCENT LIGHTING DURING DISPLAY ON COLOR STABILITY OF HIGH-OXYGEN MODIFIED ATMOSPHERE PACKAGED GROUND BEEF

Effects of temperature (OC and 4.4C) during dark storage (days 2-9) and display in non-UVand UV-filtered fluorescent lighting on color stability of high-O₂ modified atmosphere packaged "case ready" ground beef was evaluated. Minimal shift in headspace O₂ and CO₂ concentrations occurred during 9 days of storage and display. By day 3, product stored at 4.4C lost redness (Hunter +a) faster than that held at OC. Visual panel ratings for lean color decreased (P > 0.05) after 7 days but were not affected by storage temperature. When packages stored 2, 4, or 6 days at OC were displayed in light, Hunter +a values did not decline (P <0.05) for the first day and in several instances were maintained for 2 days. Panel evaluations of displayed product substantiated high maintenance of redness of lean color. UV-filtering of fluorescent lighting was not necessary for color stability of ground beef during display.     

In Vitro Fermentabilities of Purified Fiber Supplements

Six commonly used dietary fiber supplements (pectin, tragacanth gum, psyllium gum, guar gum, soy fiber and cellulose) were fermented in vitro with human fecal microbiota for 4, 8,12, and 24 hr. Short chain fatty acids (SCFA), hydrogen and methane productions, and neutral-detergent fiber digestibility differed significantly with fiber source. The most rapid fermentation rate was with pectin followed by psyllium gum, tragacanth gum, guar gum, soy fiber, and finally cellulose. Such differences in fermentability should be considered when food products are formulated. Dietary fiber source and intake may also affect breath hydrogen measurements and estimates of available carbohydrate malabsorption.