The Kinetics of Spinning-Disc Atomizers Applied to Seed Treatment Machinery1

Spinning disc-atomizers are widely used in seed-dressing machines. They not only give an initial velocity to the droplet but deliver air as well, consequently the droplet enters a moving medium. Computer analysis shows the influence of this mutual motion in the case of linear, parabolic and hyperbolic air velocity decrease. The moving air exerts a significant effect on the ideal encounter zone of liquid and seed. This effect should be taken into consideration in designing the dressing chamber of seed treatment machinery.     

Survival of chromium-51-labeled autologous and homologous erythrocytes in goats.

Apparent half-survival time of 51-Cr-tagged caprine erythrocytes after autotransfusion was 8 days. The 51Cr-tagged homologous caprine erythrocytes disappeared from circulation very rapidly, thereby indicating that it is not possible to produce sustained polycythemia in goats by hypertransfusing them with homologous erythrocytes without appropriate matching.     

Chronic vascular catheterisation of the koala and the rabbit

SUMMARY: Vascular access ports were surgically placed, first in rabbits maintained under laboratory conditions, and then in koalas maintained in a wildlife park. The ports remained patent for 9 months in rabbits and for up to 13 months in the koalas and were removed successfully. They allowed collection of blood samples without assistance or disturbance in koalas, and without stress as reflected by plasma cortisol concentration. The use of retention rings on the cannula tubing is recommended.     

Development of a sandwich-dot enzyme linked immunosorbent assay for Streptococcus pneumoniae antigen detection in cerebrospinal fluid

A new sandwich dot-enzyme linked immunosorbent assay (sdot-ELISA) was developed using omniserum prepared against different strains of Streptococcus pneumoniae as capture antibody and also as second or revealing antibody after its conjugation with horseradish peroxidase (HRP) for detection of pneumococcal antigen in cerebrospinal fluid (CSF). A total of 103 CSF samples of different categories were screened with newly developed dot-ELISA and results were compared with commercially available latex agglutination (LA) kit. The newly developed sdot-ELISA was more sensitive than LA test and can be used as an alternative diagnostic tool in laboratory and in field conditions. An added advantage of this ELISA system was that it did not require antibodies produced in two different animal species.     

Comparison of three techniques for the diagnosis of urinary tract infections in dogs with urolithiasis

OBJECTIVES: To identify an appropriate sampling technique(s) to accurately detect the bacteria causing urinary tract infections in dogs with urolithiasis. METHODS: Twenty-one dogs with urolithiasis were included in the study. Three types of samples were taken from each dog. Urine was collected by cystocentesis, and a urinary bladder mucosal biopsy and urolith were retrieved during cystotomy. The samples were then cultured on blood agar and MacConkey's agar to identify the bacteria associated with urinary tract infections. RESULTS: Bacterial urinary tract infection was found in 16 cases (76.19 per cent). The most prevalent bacteria found to cause urinary tract infection were Escherichia coli (n=7), followed by coagulase-positive Staphylococcus species (n=4), Klebsiella pneumoniae (n=2), Pseudomonas aeruginosa (n=2) and Proteus mirabilis (n=1). In the case of a positive urine culture, the same bacteria were also cultured from the urinary bladder mucosal biopsy alone or from both the urinary bladder mucosal biopsy and urolith. However, in the case of a negative urine culture, bacteria were found to be present in the urinary bladder mucosal biopsy or urolith cultures in 23.81 per cent of dogs. The uroliths that gave positive culture results were either infection-induced uroliths composed of struvite and calcium carbonate phosphate, ammonium acid urate only or metabolic uroliths composed of calcium oxalate and calcium phosphate, or calcium phosphate only. All the uroliths that gave negative culture results were metabolic uroliths composed of calcium oxalate and/or calcium phosphate, and uric acid and calcium phosphate. CLINICAL SIGNIFICANCE: When the culture from the urine obtained by cystocentesis is negative, cultures of urinary bladder mucosal biopsy and urolith are recommended in dogs with urolithiasis in order to accurately assess the microbiological status of the urinary tract.     

Analysis of soil moisture variation by forest cover structure in lower western Himalayas, India

Soil moisture affects various hydrological processes, including evapotranspiration, infiltration, and runoff. Forested areas in the lower western Himalaya in India constitute the headwater catchments for many hill streams and have experienced degradation in forest cover due to grazing, deforestation and other human activities. This change in forest cover is likely to alter the soil moisture regime and, consequently, flow regimes in streams. The effect of change in forest cover on soil moisture regimes of this dry region has not been studied through long term field observations. We monitored soil matric potentials in two small watersheds in the lower western Himalaya of India. The watersheds consisted of homogeneous land covers of moderately dense oak forest and moderately degraded mixed oak forest. Observations were recorded at three sites at three depths in each watershed at fortnightly intervals for a period of three years. The soil moisture contents derived from soil potential measurements were analyzed to understand the spatial, temporal and profile variations under the two structures of forest cover. The analysis revealed large variations in soil moisture storage at different sites and depths and also during different seasons in each watershed. Mean soil moisture storage during monsoon, winter and summer seasons was higher under dense forest than under degraded forest. Highest soil moisture content occurred at shallow soil profiles, decreasing with depth in both watersheds. A high positive correlation was found between tree density and soil moisture content. Mean soil moisture content over the entire study period was higher under dense forest than under degraded forest. This indicated a potential for soil water storage under well managed oak forest. Because soil water storage is vital for sustenance of low flows, attention is needed on the management of oak forests in the Himalayan region.