IRON AND ALUMINIUM AS CEMENTING SUBSTANCES OF SOIL AGGREGATES

A method is described for extracting fractions of soil iron and aluminium without removing organic matter. The extraction is by acetylacetone in a non–polar solvent and is virtually complete in zoo h. Similar amounts of iron and aluminium are extracted by acetylacetone in either benzene or water, but organic matter is extracted in detectable amounts only by acetylacetone in water. Extraction in aqueous solution after acetylacetone in benzene removes only organic matter, with no appreciable release of iron and aluminium. Metals extracted by acetylacetone in benzene are therefore considered to be bonded to that part of the organic matter which is extracted by acetylacetone. Water alone does not extract significant amounts of organic matter after removal of iron and aluminium by acetylacetone in benzene. The refolding of the hydrophilic surface units of the organic matter, caused by non–polar solvents, may hinder the extraction by water.     

USE OF ULTRASONOGRAPHY AND CONTRAST RADIOGRAPHY FOR SNAKE GENDER DETERMINATION

The purpose of this paper is to characterize the sonographic and radiographic features of hemipenes in male snakes and to use these features for gender determination. The sonographic and radiographic examination of 17 male and 10 female snakes, whose gender was determined previously by probing, were evaluated by one examiner who was unaware of the gender. Sonographically, hemipenes appeared funnel shaped with an echogenic thin wall and hypo to anechoic contents. Radiographically, hemipenes filled by positive contrast medium appeared as funnel-shaped radiopacities pointing caudally. Snake gender was correctly determined in all snakes using sonography (accuracy=100%). Radiographic accuracy was 81.4%. Interpretation of radiographic examinations was limited by poor distribution of the contrast medium within the hemipenes.     

Relationships between substituted urea herbicides and soil urease activity

Fenuron, monuron, diuron, siduron, linuron and neburon were tested for their inhibition of soil urease activity in order to investigate relationships between fertilizers and herbicides. The inhibition of urea hydrolysis in the selected soils was 10–33% for fenuron, 10–39% for monuron, 10–35% for diuron, 8–38% for siduron, 9–36% for linuron and 12–30% for neburon. In the field greater effects might be expected since the fertilizer/herbicide ratio would be lower than the one considered here. Some agronomic aspects of the relationship between fertilizers and herbicides are discussed.     

ULTRASONOGRAPHIC FEATURES OF CANINE LIPOMAS

The purpose of this study was to evaluate the ultrasonographic features of canine lipomas. A group of 94 dogs with a soft tissue mass was considered. All dogs were examined ultrasonographically and cyto/histologic examination was performed. Twenty-four dogs, whose mass was diagnosed as a lipoma, were selected. Fifty-five lipomas were present on the 24 dogs. Fifty-one lipomas were superficial and located subcutaneously. Four lipomas were deep and located in the paratesticular region. Ultrasonographically, lipomas appeared as oval, well-defined, encapsulated, striated masses.