Ideology and agricultural technology in the late twentieth century: Biotechnology as symbol and substance

The significance of biotechnology in agriculture during the late twentieth century has been as much in the realm of symbol and ideology as in its political economy. The ideological roots of biotechnology are long historical ones. The ideology of productivism, which was codified during mid-century out of a coincidence of interest among experiment stations, USDA, Congress, agribusiness, and agricultural commodity groups, has encountered numerous challenges since the 1970s. One of the major responses to the crisis of productionism was to forge a social definition of biotechnology as being a revolutionary technology. I conclude by discussing whether biotechnology, as both symbol and substance, is likely to be a basis for attempts to resuscitate productivism in the 1990s now that biotechnology is being demystified, its limits being appreciated, and its opposition still considerable.Frederick H. Buttel is Professor of Rural Sociology and Director of the Agricultural Technology and Family Farm Institute at the University of Wisconsin, Madison. His major areas of interest are the sociology of science, sociology of agriculture, and environmental sociology. Prior to joining the University of Wisconsin faculty, he was Professor of Rural Sociology and Science and Technology Studies at Cornell University. In 1987 he was elected a Fellow of the American Association for the Advancement of Science. During 1990–91 he served as President of the Rural Sociological Society, and from 1989–92 he served as a member of the Council of the Agriculture, Food, and Human Values Society.     

Initiation of angiogenesis by human follicular fluid

Angiogenesis was observed and measured after injection of human follicular fluid into rabbit corneas. Undiluted human follicular fluid stimulated angiogenesis in every case, with new blood vessels visible 3 days after injection and extending 2.0 millimeters from the corneal scleral limbus into the injection site by day 15. Stimulation of angiogenesis was lost by heating or diluting the follicular fluid but was retained after charcoal stripping or dialysis. Human follicular fluid contains an angiogenic factor that may be associated with perifollicular neovascularization during folliculogenesis.     

Adsorption of bacteria on soils: Experiments,thermodynamic rationale,and application

A model for the adsorption of bacteria to soil particles is described using the physical-chemical Langmuir isotherm and the van't Hoff equation. An example of the use of the model for assessing bacterial movement through soil is provided.Staphylococcus aureus was the sorbate with sorbents of activated charcoal, kaolinite clay, Mendon silt loam, and silica sand. Competitive agents sodium lauryl sulfate, sodium chloride, and peptone were also studied. Peptone was the most successful competitor with the bacteria for sites on the sorbent.     

Platy Quartz Phytoliths found in the Fossil Forest Deposits,Axel Heiberg Island,Northwest Territories,Canada

The occurrence of quartz particles having a platy morphology found in the white layers within the fossil forest deposits of Axel Heiberg Island, was further confirmed by optical and electron microscopic examinations. The platy quartz crystals were concentrated in the finer fractions. The δ ₁₈O values of fractions enriched in platy quartz crystals ranged from +13.7 to +16.6 %₀. These values were higher than those obtained for coarser fractions. The platy morphology and crystallographic character of the quartz particles concentrated in the finer size fractions are uncharacteristic both of aerosol derived material and of secondary silica. These findings and information available for the paleoenvironment of the study area favor a biogenic origin for the platy quartz. The oxygen-isotope data are consistent with this hypothesis.     

Restoring the capacity of spent mushroom compost to treat coal mine drainage by reducing the inflow rate: A microcosm experiment

Four volumes of spent mushroom compost were exposed to synthetic coal mine drainage (pH 3.5, 48 mg L^?1 Fe, 22 mg L^?1 Mn) under oxidizing conditions (Eh 300 to 400 mV) at a relatively high rate of flow. After 15 days, the compost lost its ability to elevate pH, to lower the redox potential, to lower outlet iron concentrations, and to lower manganese concentrations, with larger volumes retaining more Fe and H⁺, but less Mn. Estimated retention maxima per liter of spent mushroom compost were 281 μeq H⁺, 5.56 g Fe, and 0.15 g Mn. These values are similar to those reported elsewhere for peat. The ‘saturated’ compost was then mixed and exposed to mine water in order to eliminate ‘dead zones’ in the compost. Subsequently, the compost was re-exposed to synthetic mine water (pH 4.0, 60 mg L^?1 Fe, O mg L^?1 Mn) under a much lower flow rate and less oxidizing regime for a period of 114 days. Under the low flow regime, iron was first exported from the compost as reducing conditions were established, and then retained on a stable basis. In addition, Eh was lowered and pH was elevated by the compost. On a net basis, the capacity of the compost to retain iron was increased and apparently stable under the decreased flow conditions.     

Prevalence and genotyping of Giardia duodenalis from beef calves in Alberta,Canada

Giardia infections in domestic cattle has come under increasing scrutiny owing to the potential contamination of surface and ground waters through manure distribution on fields and pasture runoff. The objective of the study was to determine the prevalence and genotypes of Giardia duodenalis in beef calves in major beef cow calf farms in Alberta, Canada. Fecal samples were collected from beef calves aged 2-10 weeks at nine farms in Alberta. Samples were examined for the presence of G. duodenalis cysts by immunofluorescent staining. Giardia cysts were found in 168 of the 495 fecal samples examined, with prevalence ranging from 7 to 60% among farms. Genotypic analysis of positive isolates utilizing PCR and sequencing of a 292 bp fragment of the 16S-rRNA locus, revealed the hoofed livestock genotype in 41 of the 42 isolates. One isolate was identical to the Assemblage A genotype. The results of this study demonstrate that beef calves in this area are primarily infected with the livestock genotype which is thought to be specific to artiodactyl hosts and non-infective to humans. This suggests that the Giardia carried by beef cattle may be a minimal zoonotic threat.