Tetragonal Zirconium Oxide Prepared under High Pressure

Tetragonal zirconium oxide, stable at room temperature, was synthesized at 15 to 20 kb and 12000 to 17000C. Rapid quenching produced a mixture of the monoclinic and tetragonal phases. The high-pressure specimens, when heated to 1200 degrees C in air and quenched, reverted to the all-monoclinic form.     

Characterization of infectious bursal disease viruses isolated in 2007 from Delmarva commercial broiler chickens

A study was performed in 2007 to isolate and characterize infectious bursal disease viruses (IBDVs) in commercial broilers grown in the Delmarva (DMV) Peninsula region of the United States. Bursae of Fabricius were collected weekly from 1 to 4 wk of age from broilers on 10 farms with a history of poor performance. Microscopic pathology was used to determine the infectious bursal disease (IBD) status of the broilers. Bursae from 1- and 2-wk-old broilers did not show IBD microscopic lesions. Moreover, broilers on 1 of the 10 farms were IBD lesion free at 3 and 4 wk of age. However, 3 of 9 and 9 of 9 farms yielded broilers with IBD-affected bursae from 3- and 4-wk-old commercial broilers, respectively. Ten IBDV isolates were recovered from 3 of 3 lesion-positive bursal pools at 3 wk of age and 7 of 9 lesion-positive bursal pools at 4 wk of age. Analysis of the viral protein (VP) 2 genes identified all isolates as serotype 1 Delaware (Del) variant viruses. Five field isolates, each representing different molecular clades of the Delaware variant viruses, were selected for further study. Experimental infection of specific-pathogen-free white leghorn chickens with isolates DMV/4813/07, DMV/4947/07, DMV/4955/07, DMV/5038/07, and DMV/5041/07 produced gross and microscopic pathology of the bursa consistent with Delaware variant infection. Monoclonal antibody testing showed DMV/4813/07, DMV/4947/07, DMV/ 4955/07, and DMV/5041/07 to be similar to previous recognized variant viruses. However, DMV/5038/07 was found to be unreactive with the monoclonal antibodies that typically recognize reference strains STC, Del E, GLS, RS593, and AL2. In a challenge of immunity study, 10-day-old progeny from breeders immunized with a commercially available inactivated IBDV vaccine containing the Del E and classic strains were protected to a lesser degree against isolate DMV/5038/07 compared to Del E challenge based on microscopic lesion scores (P < 0.01) of the bursa. This result suggests the virus is antigenically different from the Del E strain contained in the vaccine. Collectively, the monoclonal antibody and progeny challenge of immunity findings suggest DMV/5038/07 is antigenically different from the Del E strain contained in the vaccine.     

The kinetics-based enzyme-linked immunosorbent assay for coronavirus antibodies in cats: calibration to the indirect immunofluorescence assay and computerized standardization of results through normalization to control values.

The computer-assisted, kinetics-based enzyme-linked immunosorbent assay for coronavirus antibodies in cats was calibrated to the conventional indirect immunofluorescence assay by linear regression analysis and computerized interpolation (generation of "immunofluorescence assay-equivalent" titers). Procedures were developed for normalization and standardization of kinetics-based enzyme-linked immunosorbent assay results through incorporation of five different control sera of predetermined ("expected") titer in daily runs. When used with such sera and with computer assistance, the kinetics-based enzyme-linked immunosorbent assay minimized both within-run and between-run variability while allowing also for efficient data reduction and statistical analysis and reporting of results.     

The influence of perfusate volume on antimicrobial concentration in synovial fluid following intravenous regional limb perfusion in the standing horse

This study investigated the influence of perfusate volume on antimicrobial concentration in synovial fluid following intravenous regional limb perfusion (IVRLP) and assessed the efficacy of low volume IVRLP. The front limbs of 9 horses were randomly assigned to 1 of 3 volume groups: 10 mL (Group 1), 30 mL (Group 2), or 60 mL (Group 3). A tourniquet was applied distal to the carpus and the limbs were perfused with 500 mg genta-micin diluted to the assigned volume via a catheter placed in the lateral palmar digital vein at the level of the proximal sesamoid bones. Synovial fluid samples were collected from the metacarpophalangeal joint at 30 minutes, followed by removal of the tourniquet. Gentamicin concentration in synovial fluid was detected using a fluorescence polarization immunoassay. There were no statistically significant differences among gentamicin concentrations in synovial fluid among perfusate volume groups. Mean gentamicin concentration in Group 1 (125.9 μg/mL) was higher than Group 2 (82.7 μg/mL) and Group 3 (56.1 μg/mL).     

Migration of nonylphenol from plastic containers to water and a milk surrogate

Nonylphenol (NP) is used as an antioxidant and plasticizer in some plastic products. After the discovery of its endocrine-disrupting potential, concern over human exposure to this chemical has increased. Recently, a group in Germany estimated the average daily intake of NP from food (7.5 microg/day), excluding water. In the present study, NP, octylphenol (OP), and their respective ethoxylates (1-5) were measured in spring water bottled in three different types of plastic (HDPE, PET, and PVC). NP was present in water from HDPE and PVC containers, at 180 and 300 ng/L respectively, which represent 4.8% and 8% of the value calculated by the German group assuming a consumption of 2 L of water per day. OP was found in water from HDPE extracts in lower amounts, 12 ng/L, and neither the NP- nor the OP-ethoxylates were detected in any of the samples. Attempts to measure these compounds in tap water were unsuccessful, probably because reaction with residual chlorine results in the formation of chlorinated byproducts. Migration of NP from HDPE containers to a milk surrogate was also evaluated; results indicate that the amounts of NP leaching into milk might be similar to those in bottled water.     

Magma flow instability and cyclic activity at soufriere hills volcano, montserrat, british west indies

Dome growth at the Soufriere Hills volcano (1996 to 1998) was frequently accompanied by repetitive cycles of earthquakes, ground deformation, degassing, and explosive eruptions. The cycles reflected unsteady conduit flow of volatile-charged magma resulting from gas exsolution, rheological stiffening, and pressurization. The cycles, over hours to days, initiated when degassed stiff magma retarded flow in the upper conduit. Conduit pressure built with gas exsolution, causing shallow seismicity and edifice inflation. Magma and gas were then expelled and the edifice deflated. The repeat time-scale is controlled by magma ascent rates, degassing, and microlite crystallization kinetics. Cyclic behavior allows short-term forecasting of timing, and of eruption style related to explosivity potential.     

Alteration of lymphocyte trafficking by sphingosine-1-phosphate receptor agonists

Blood lymphocyte numbers, essential for the development of efficient immune responses, are maintained by recirculation through secondary lymphoid organs. We show that lymphocyte trafficking is altered by the lysophospholipid sphingosine-1-phosphate (S1P) and by a phosphoryl metabolite of the immunosuppressive agent FTY720. Both species were high-affinity agonists of at least four of the five S1P receptors. These agonists produce lymphopenia in blood and thoracic duct lymph by sequestration of lymphocytes in lymph nodes, but not spleen. S1P receptor agonists induced emptying of lymphoid sinuses by retention of lymphocytes on the abluminal side of sinus-lining endothelium and inhibition of egress into lymph. Inhibition of lymphocyte recirculation by activation of S1P receptors may result in therapeutically useful immunosuppression.