18 research outputs found
Solar parameters for modeling interplanetary background
The goal of the Fully Online Datacenter of Ultraviolet Emissions (FONDUE)
Working Team of the International Space Science Institute in Bern, Switzerland,
was to establish a common calibration of various UV and EUV heliospheric
observations, both spectroscopic and photometric. Realization of this goal
required an up-to-date model of spatial distribution of neutral interstellar
hydrogen in the heliosphere, and to that end, a credible model of the radiation
pressure and ionization processes was needed. This chapter describes the solar
factors shaping the distribution of neutral interstellar H in the heliosphere.
Presented are the solar Lyman-alpha flux and the solar Lyman-alpha resonant
radiation pressure force acting on neutral H atoms in the heliosphere, solar
EUV radiation and the photoionization of heliospheric hydrogen, and their
evolution in time and the still hypothetical variation with heliolatitude.
Further, solar wind and its evolution with solar activity is presented in the
context of the charge exchange ionization of heliospheric hydrogen, and in the
context of dynamic pressure variations. Also the electron ionization and its
variation with time, heliolatitude, and solar distance is presented. After a
review of all of those topics, we present an interim model of solar wind and
the other solar factors based on up-to-date in situ and remote sensing
observations of solar wind. Results of this effort will further be utilised to
improve on the model of solar wind evolution, which will be an invaluable asset
in all heliospheric measurements, including, among others, the observations of
Energetic Neutral Atoms by the Interstellar Boundary Explorer (IBEX).Comment: Chapter 2 in the planned "Cross-Calibration of Past and Present Far
UV Spectra of Solar System Objects and the Heliosphere", ISSI Scientific
Report No 12, ed. R.M. Bonnet, E. Quemerais, M. Snow, Springe
AlteraçÔes anatÎmicas induzidas por Meloidogyne enterolobii (=M. mayaguensis) e Meloidogyne javanica em tomateiros resistentes a meloidoginose
A resistĂȘncia de tomateiros (Solanum lycopersicum L.) a M. incognita, M. javanica e M. arenaria, conferida pela presença do gene Mi, nĂŁo contempla a espĂ©cie M. enterolobii (=M. mayaguensis). O objetivo da pesquisa foi verificar as alteraçÔes anatĂŽmicas causadas por M. enterolobii no sistema radicular de porta-enxertos de tomateiro com o gene de resistĂȘncia Mi ('Magnet' e Helper M') e comparĂĄ-las com as causadas por M. javanica. As observaçÔes anatĂŽmicas das raĂzes foram feitas com auxĂlio de microscĂłpio de luz e os aspectos mais relevantes foram fotografados. Com base em contagens e mensuraçÔes do tamanho dos sĂtios de alimentação e das cĂ©lulas gigantes, foram efetuadas analises utilizando o mĂ©todo estatĂstico de AnĂĄlise de Agrupamento. O aparecimento de cĂ©lulas nutridoras incitadas por M. enterolobii foi verificado em ambos os porta-enxertos de tomateiro, entre 10 e 17 dias apĂłs a inoculação (DAI). O nĂșmero e a ĂĄrea de sĂtios de alimentação e de cĂ©lulas gigantes foram menores aos 17 DAI do que aos 24 DAI. Nesta Ă©poca (24 DAI), foram observados sĂtios de alimentação constituĂdos pela presença de vĂĄrias cĂ©lulas nutridoras multinucleadas, com parede celular espessa, citoplasma denso e granuloso. Os tecidos vasculares apresentaram-se comprimidos e desorganizados, foi observada, tambĂ©m, hipertrofia de cĂ©lulas do parĂȘnquima cortical. As raĂzes inoculadas com M. javanica nĂŁo apresentaram alteraçÔes anatĂŽmicas