Comparison of recovery times and complication rates between a modified slanted slot and the standard ventral slot for the treatment of cervical disc disease in 20 dogs

OBJECTIVES: To compare the recovery times and complication rates between the standard ventral slot and the modified slanted ventral slot for the treatment of cervical disc disease in dogs with the same neurological grade. METHODS: A retrospective analysis of an equal number of cervical disc cases for each procedure was carried out specifically to determine the recovery times and complication rates. To allow for meaningful comparison only dogs that had the same neurological grade were selected. Outcomes were determined by time to recover and the resolution of symptoms and complications were graded in terms of severity. RESULTS: The standard ventral slot cases had a higher complication rate than the modified slanted slot cases with one case dying in the postoperative period. However, the modified slanted slot cases on average had a marginally slower recovery time than standard ventral slot cases. CLINICAL SIGNIFICANCE: Ventral decompression using the modified slanted slot instead of the standard ventral slot will allow for spinal decompression with potentially less destabilisation, and incur a similar incidence of complications and rate of recovery.     

Onchocerca sp. in an imported Zangersheide gelding causing suspensory ligament desmitis

A 5-year-old imported Zangersheide gelding was evaluated for SC swellings over both forelimbs and lameness localized to the distal metacarpus. Ultrasound examination of the SC masses was compatible with verminous granulomas. Linear hyperechoic foci were present within the suspensory ligament branches of both forelimbs, suggestive of ligamentous parasitic infiltrates. A diagnosis of onchocerciasis was confirmed on biopsy of a SC mass. The gelding was treated with ivermectin and a tapering course of PO dexamethasone but was eventually euthanized. Necropsy confirmed the presence of SC eosinophilic granulomas and degenerative suspensory ligament desmitis, both with intralesional nematodes. Given the location and appearance of the nematode, a diagnosis of Onchocerca sp., most likely O. reticulata, was made. Onchocerciasis should be included as a differential diagnosis for multifocal suspensory ligament desmitis with these sonographic characteristics when paired with SC masses in imported European Warmbloods.     

Comparison of Free Air Space Test Methods

Air space within a compost material can be measured using several methods. This project, focusing on bulking materials, compared five air space (AS) test methods: particle density (PD) method, modified PD (MPD) method, air pycnometer (AP) method, modified air pycnometer (MAP), and a quick method. There were significant differences between results obtained using the different tests. PD and MAP methods yielded results representing total air space (TAS), while the AP and MPD methods yielded values which were thought to represent free air space (FAS). The Quick method resulted in AS values dramatically different from the other methods, and further development and validation of the method was recommended. The MPD was found to be unsuitable for samples containing fine material, such as biosolids. Both the PD and the MAP tests were precise; however, results were biased to TAS values. This was illustrated through the similarity between AS values measured by the two tests and the predicted TAS. The MAP was the simplest method and was recommended for use with compost samples. Strong linear correlations were observed between TAS and bulk density (BD; kg m^?3: TAS = 100 – 0.096*BD (R²=0.98) for PD and 100 – 0.090*BD (R²=0.90) for MAP. The effect of storage time on FAS, TAS, and moisture content was examined in this study. Straw samples were stored for a month and showed no change in the physical properties. Woodchip samples were stored for over 5 months. A slight change in both FAS and TAS was observed, but the differences were minor compared to variations induced by different particle sizes and moisture levels.     

Relative contributions of sedimentation and impaction to deposition of particles in a crop canopy

Lycopodium spores were released steadily into the air during 20–30 min from a line source positioned within a wheat crop. The spores were trapped on sticky strips held at angles, π, of 0, 30, 60 and 90° with respect to the horizontal and oriented to face the mean wind direction and on sticky, vertical glass rods. The aerial spore concentration, C, was measured by small suction traps. Deposits of the spores on wheat leaves were obtained from sections of leaves whose posture in the canopy was nearly horizontal, nearly vertical, or at angles between 30 and 60°. Number of spores per m² for all trapping surfaces were obtained by counting under a microscope. Experiments were conducted on seven different days, encompassing friction velocities, u^*, of 0.27–0.50 m s⁻¹. The rate of deposition on angled surfaces, D(π), was given approximately by D(θ) = D(0) cos (θ) + D(90) sin (θ), where D(0) and D(90) were the observed rate of deposit on horizontal and on vertical surfaces, respectively. Below mid-canopy height, inertial impaction of spores was negligible, so that D(90) = 0 for all the trap surfaces. There, D(0) was mainly due to sedimentation and was very nearly equal to v_s·C, where v_s is the settling speed of the spore in still air. Near the top of the canopy, deposition on sticky surfaces was enhanced by inertial impaction and turbulent deposition, so that D(0) was about twice that expected from sedimentation and D(90) was about five times larger than expected from inertial impaction at the mean wind speed. Nevertheless, considering the vertical distribution of leaf area and the angles of leaves in a wheat canopy, the rate of deposition of spores for the entire depth of a wheat canopy can be calculated with a probable underestimation of only 20% by simply assuming sedimentation on horizontally projected area and impaction on vertically projected area.     

The elemental composition of asteroid 433 eros: results of the NEAR-shoemaker X-ray spectrometer

We report major element composition ratios for regions of the asteroid 433 Eros imaged during two solar flares and quiet sun conditions during the period of May to July 2000. Low aluminum abundances for all regions argue against global differentiation of Eros. Magnesium/silicon, aluminum/silicon, calcium/silicon, and iron/silicon ratios are best interpreted as a relatively primitive, chondritic composition. Marked depletions in sulfur and possible aluminum and calcium depletions, relative to ordinary chondrites, may represent signatures of limited partial melting or impact volatilization.     

The struggle to govern the commons

Human institutions--ways of organizing activities--affect the resilience of the environment. Locally evolved institutional arrangements governed by stable communities and buffered from outside forces have sustained resources successfully for centuries, although they often fail when rapid change occurs. Ideal conditions for governance are increasingly rare. Critical problems, such as transboundary pollution, tropical deforestation, and climate change, are at larger scales and involve nonlocal influences. Promising strategies for addressing these problems include dialogue among interested parties, officials, and scientists; complex, redundant, and layered institutions; a mix of institutional types; and designs that facilitate experimentation, learning, and change.     

Electric charge,image-charge forces,and the deposition of pesticide drops

A simulation model has been developed and used to assess the importance of induced image-charge forces in enhancing the deposition on plant stems and leaves of charged, as compared to uncharged, pesticide drops. The model, through calculations of the dynamics and trajectories of individual drops, allows separate determinations of enhancements of the deposit on the upper and lower leaf surfaces. Trajectories and rates of deposition were computed for water drops having diameters within the range 20 to 100 μm, for charges q between 0.1 and 1.0 times the maximum charge Q that can be retained on a drop of specified radius r, for wind speeds μo of the order of 0.1 to 1 .O ms^?1, and for plant stems (represented by vertical cylinders) 2 and 10 mm in diameter, and for plant leaves (horizontal plates) of various along-wind lengths I. It is shown that the rates of impaction to stems can be described in terms ot two dimensionless parameters that respectively relate to the properties of the particle and of the image force, and the rates of sedimentation to horizontal leaves in terms of the parameters q, r and l/μ_o. The model predicts that, inside crop canopies, considerable increases in the rates both of impaction and sedimentation can be achieved if drops, particularly small drops, can be given charges close to their respective Q. Thus for drops of 20 μm in diameter, sedimentation under typical within-canopy conditions is predicted to increase five-fold as a result of charging the drops, one-half of the enhanced deposit being on the underside of the leaves. For drops of 40 μ in diameter, predictions for the enhancement of deposition on the uppermost leaves of a field bean crop are shown to agree with published results from a field trial of an electrostatic crop spray system.