Cardiopulmonary effects and recovery characteristics of horses anesthetized with xylazine–ketamine with midazolam or propofol

Objective

To evaluate cardiopulmonary and recovery characteristics of horses administered total intravenous anesthesia (TIVA) with xylazine and ketamine combined with midazolam or propofol.

Shear-wave splitting and implications for mantle flow beneath the MELT region of the east pacific rise

Shear-wave splitting across the fast-spreading East Pacific Rise has been measured from records of SKS and SKKS phases on the ocean-bottom seismometers of the Mantle Electromagnetic and Tomography (MELT) Experiment. The direction of fast shear-wave polarization is aligned parallel to the spreading direction. Delay times between fast and slow shear waves are asymmetric across the rise, and off-axis values on the Pacific Plate are twice those on the Nazca Plate. Splitting on the Pacific Plate may reflect anisotropy associated with spreading-induced flow above a depth of about 100 km, as well as a deeper contribution from warm asthenospheric return flow from the Pacific Superswell region.     

Ancient mantle in a modern arc: osmium isotopes in izu-bonin-mariana forearc peridotites

Mantle peridotites drilled from the Izu-Bonin-Mariana forearc have unradiogenic 187Os/188Os ratios (0.1193 to 0.1273), which give Proterozoic model ages of 820 to 1230 million years ago. If these peridotites are residues from magmatism during the initiation of subduction 40 to 48 million years ago, then the mantle that melted was much more depleted in incompatible elements than the source of mid-ocean ridge basalts (MORB). This result indicates that osmium isotopes record information about ancient melting events in the convecting upper mantle not recorded by incompatible lithophile isotope tracers. Subduction zones may be a graveyard for ancient depleted mantle material, and portions of the convecting upper mantle may be less radiogenic in osmium isotopes than previously recognized.     

Effect of the polyunsaturated fatty acid composition of beef muscle on the profile of aroma volatiles

The effect of n-3 polyunsaturated fatty acids (PUFAs) in beef muscle on the composition of the aroma volatiles produced during cooking was measured. The meat was obtained from groups of steers fed different supplementary fats: (i) a palm-oil-based control; (ii) bruised whole linseed, which increased muscle levels of alpha-linolenic (C18:3 n-3) and eicosapentaenoic acid (EPA, C20:5 n-3); (iii) fish oil, which increased EPA and docosahexaenoic acid (C22:6 n-3); (iv) equal quantities of linseed and fish oil. Higher levels of lipid oxidation products were found in the aroma extracts of all of the steaks with increased PUFA content, after cooking. In particular, n-alkanals, 2-alkenals, 1-alkanols, and alkylfurans were increased up to 4-fold. Most of these compounds were derived from the autoxidation of the more abundant mono- and di-unsaturated fatty acids during cooking, and such autoxidation appeared to be promoted by increased levels of PUFAs.     

Ranavirus-associated morbidity and mortality in a group of captive eastern box turtles (Terrapene carolina carolina).

Seven captive eastern box turtles (Terrapene carolina carolina) from a large collection of North American chelonians in North Carolina became acutely ill in the fall of 2002. Five of the turtles died. Clinical signs included cutaneous abscessation, oral ulceration or abscessation (or both), respiratory distress, anorexia, and lethargy. The predominant postmortem lesion was fibrinoid vasculitis of various organs, including skin, mucous membranes, lungs, and liver. No inclusion bodies were detected by histopathology or electron microscopy of formalin-fixed tissue. An iridovirus was isolated from tissues obtained postmortem from two of the box turtles that died. The virus was characterized by electron microscopy, polymerase chain reaction, and sequence analysis of a portion of the major capsid protein as a member of the genus Ranavirus.     

The accumulation of cosmogenic chlorine-36 in rocks: a method for surface exposure dating

Because of the reaction of cosmic rays with elements in minerals, chlorine-36 accumulates in rocks exposed at the earth's surface. This suggests that the ratio of chlorine-36 to stable chloride can be used as a geochronometer. Reasonable agreement has been obtained between measurements of chlorine-36 in volcanic rocks of known age and calculations of chlorine-36 production based on rock composition and cosmicray flux. The buildup of chlorine-36 should be a useful means for measuring the surface exposure time of young volcanic rocks and geomorphic features in the age range of 10(3) to 10(6) years.     

Waterjet injection of powdered activated carbon for sediment remediation

Purpose  

In situ contaminated sediment remediation through the addition of activated carbon has been proven to be an effective remediation technique. An amendment delivery system was developed to accurately place and inject a powdered activated carbon slurry. The system was set up to deliver a series of discrete injections over a rectangular grid with the objective to deliver 3% carbon (C) by dry weight to an inundated saturated sediment at a maximum sediment depth of 30 cm.