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During recent years in Denmark higher rates of antibodies to Coxiella burnetii have been detected in animals and humans than previously reported. A study based on bulk tank milk samples from 100 randomly selected dairy herds was performed to estimate the prevalence and geographical distribution of antibody positive dairy herds. Using the CHEKIT Q-Fever Antibody ELISA Test Kit (IDEXX), the study demonstrated a prevalence of 59% antibody positive herds, 11% antibody intermediate herds and 30% antibody negative herds based on the instructions provided by the manufacturer. The geographical distribution does not indicate a relationship between the regional density of dairy farms and the prevalence of antibody positive dairy farms. The result supports the hypothesis of an increase in the prevalence of positive dairy herds compared to previous years.

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Longitudinal Schottky signals from a laser-cooled, spatially dense, ion beam have been studied in the ASTRID storage ring. The fluctuation signals are distorted by the effects of space charge, as is observed in electron cooling experiments.However, the spectra also exhibit previously unobserved coherent components.The ions' velocity distribution, measured by a laser fluorescence technique, suggests that the coherence is due to suppression of Landau damping. The observed behavior has important implications for the attainment of a crystalline ion beam in a storage ring.PACS numbers: 41.75. Ak, 29.20.Dh, 29.27.Bd, 52.25.Wz In this Letter we describe measurements of longitudinal Schottky signals from a unique physical system, a spatially dense, very cold (i.e., having very small velocity spread) ion beam produced by laser cooling. This system has direct relevance to the understanding of the ultimate limits to the quality of a stored ion beam. In particular, the possibility of producing a crystalline ion beam [1] is usually associated with the technique of laser cooling.Schottky signals [2] are used as a powerful diagnostic