RESUMO
In the late winter of 2003, a number of livestock animals in the Midwest were poisoned due the accidental contamination of a popular commercial feed with a lethal additive. Although all the evidence indicates this incident had no malicious or terrorist intent, it is informative as a case study highlighting potential security implications with respect to a terrorist event directed at U.S. agriculture.
Assuntos
Agricultura , Doenças dos Animais/induzido quimicamente , Doenças dos Animais/prevenção & controle , Ração Animal , Camelídeos Americanos , Contaminação de Alimentos/prevenção & controle , Terrorismo/prevenção & controle , Agricultura/história , Agricultura/normas , Animais , Abastecimento de Alimentos/normas , História do Século XX , História do Século XXI , Humanos , Ionóforos/intoxicação , Piranos/intoxicação , Medidas de Segurança , Terrorismo/históriaRESUMO
Using a near-field scanning optical microscope (NSOM), crystals of zinc-porphyrin network materials are characterized with respect to morphology and fluorescence. Needle-shaped crystals are observed. While the topography is flat, the fluorescence intensity profile in the width direction is approximately triangular. A numerical calculation shows that differences between the topographic and optical images cannot be due to an artifact. In some needle-shaped crystals, the fluorescence emission is strongly peaked at one or both ends, possibly indicating a polar crystal structure.