96 research outputs found
Development of a PCR assay for the detection of animal tissues in ruminant feeds.
The European Community ban on use of meat and bone meal in ruminant feed, as a consequence of the spread of bovine spongiform encephalopathy in Europe, has prompted a number of investigations about the possibility of detecting animal tissues in feedstuff. In this paper, a study on vertebrate primers, designed in the 16S rRNA gene of mitochondrial DNA, is described. These primers were able to amplify fragments that contained between 234 and 265 bp. The fragments were specific for bovine, porcine, goat, sheep, horse, rabbit, chicken, trout, and European pilchard and were confirmed by sequence analysis amplicons. The primers were used in a PCR assay applied to five samples of meat and blood meals of different species and subjected to severe rendering treatments (134.4 to 141.9 degrees C and 3.03 to 4.03 bar for 24 min). The presence of vertebrate tissues was detected in all samples. The assay proved to be rapid and sensitive (detection limit 0.0625%). It can be used as a routine method to detect animal-derived ingredients in animal feedstuff
Travels of a Rayed Head: imagery, fiber, structure and connotations of early textiles from the South Central Andes
The rayed head image has long been identified as a central symbol associated with the Paracas tradition, also called the sun face 1 and associated with the concept of Oculate Being developed by the Berkeley School. 2 Prominently repeated on the central ground of the famous Paracas Textile at the Brooklyn Museum, this image has much earlier antecedents in the region. Scholars disagree on the extent to which many Paracas, Topara and early Nasca images with large round eyes, grinning mouths, and serpentlike appendages emitting from the head and body may also be manifestations of a particular Oculate Being or of more general concepts of natural or supernatural power. Recently, contemporary textiles found in the Sihuas valley to the south (see Haeberli in this volume) challenge us to reexamine the similarities and distinctions among rayed heads.
One of the great challenges of the history of material culture, envisioned as a history of philosophical concepts, social values and cultural practices through their inscription in material objects, is the degree to which a recurrent image, pattern or special arrangement reflects a similar idea. A number of quite different images have been associated with the concept of an Oculate Being proposed by John Rowe and others of the Berkeley school based on their analysis of Ica valley ceramics and Ocucaje gravelots in the 1950s. I here trace the rayed head or sun face image as it occurs over at least 500 years in the region of Ica and Paracas. I then briefly consider its relationship to other contemporary imagery and later imagery featuring ray-like elements emitted from the head, both in the same contexts where the rayed head appears, and in other cemeteries to the south in southern Peru and northern Chile.
All the imagery discussed here is associated with a period between about 450 BC and AD 450 called the Formative in the South Central Andes (Bolivia and northern Chile) and called the Early Horizon (or late Formative) and Early Intermediate (or Regional Development) Period in the Central Andes. Most of the images I discuss are created on textiles. While only recovered from burials on the desert coast, textile materials draw on relationships of production and exchange that spanned the Andean cordillera to the montane rainforest to the east, and stretched to the north and south. Either as clothing or cargo, textiles themselves traveled and were no doubt a primary source of non-local imagery.
I do consider related images on non-textile artifacts. I compare textile based imagery with contemporary imagery on engraved and painted ceramics and gourds to try to distinguish among design features specific to medium, style and iconography
Application of Technological Control Measures on Vehicle Pollution: A Cost-Benefit Analysis in China
Impure Public Goods and Technological Interdependencies
Impure public goods represent an important group of goods. Almost every public good exerts not only effects which are public to all but also effects which are private to the producer of this good. What is often omitted in the analysis of impure public goods is the fact that – regularly – these private effects can also be generated independently of the public good. In our analysis we focus on the effects alternative technologies – independently generating the private effects of the public good – may have on the provision of impure public goods. After the investigation in an analytical impure public good model, we numerically simulate the effects of alternative technologies in a parameterized model for climate policy in Germany
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