Eta Carinae -- Physics of the Inner Ejecta

Eta Carinae's inner ejecta are dominated observationally by the bright Weigelt blobs and their famously rich spectra of nebular emission and absorption lines. They are dense (n_e ~ 10^7 to 10^8 cm^-3), warm (T_e ~ 6000 to 7000 K) and slow moving (~40 km/s) condensations of mostly neutral (H^0) gas. Located within 1000 AU of the central star, they contain heavily CNO-processed material that was ejected from the star about a century ago. Outside the blobs, the inner ejecta include absorption-line clouds with similar conditions, plus emission-line gas that has generally lower densities and a wider range of speeds (reaching a few hundred km/s) compared to the blobs. The blobs appear to contain a negligible amount of dust and have a nearly dust-free view of the central source, but our view across the inner ejecta is severely affected by uncertain amounts of dust having a patchy distribution in the foreground. Emission lines from the inner ejecta are powered by photoionization and fluorescent processes. The variable nature of this emission, occurring in a 5.54 yr event cycle, requires specific changes to the incident flux that hold important clues to the nature of the central object.Comment: This is Chapter 5 in a book entitled: Eta Carinae and the Supernova Impostors, Kris Davidson and Roberta M. Humphreys, editors Springe

Carrot floral development and reproductive biology

The defining characteristic of the botanical family of Apiaceae (former Umbelliferae) is the inflorescence. The flowers aggregate in terminal umbels that may be commonly compound, often umbelliform cymes. Likewise, flowers of the carrot are clustered in flat, dense umbels, partially with zygomorphic petals at the edges. Carrot producers and consumers mainly consider the vegetative phase namely the storage root as vegetable. Nevertheless, the reproductive phase is an important topic for genetic research, for breeding new cultivars and seed production. Hence, an improved knowledge on the genetic control mechanisms of reproduction such as flowering time, flower development and architecture, pollen fertility and male sterility as well as seed set are of essential importance. The chapter reviews key steps on carrot floral development and reproductive biology especially under consideration of the comprehensive genomic data set recently obtained from carrot.Fil: Linke, Betina. Humboldt-Universität zu Berlin; AlemaniaFil: Alessandro, Maria Soledad. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Mendoza-San Juan. Estación Experimental Agropecuaria La Consulta; ArgentinaFil: Galmarini, Claudio Romulo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Mendoza-San Juan. Estación Experimental Agropecuaria La Consulta; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; ArgentinaFil: Nothnagel, Thomas. Institute for Breeding Research on Horticultural Crops; Alemani