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The mite Varroa destructor is an ectoparasite that is considered a major pest for beekeeping with European honey bees. However, Africanized bee colonies are less threatened by this ectoparasite, because infestation levels remain low in these bees. The low reproductive ability of female mites of the Japanese biotype (J), introduced to Brazil early in the(More)
The oviposition potential of honey bee queens decreases with age, therefore it is important to replace old queens with younger ones on a periodic basis. However, queen replacement is problematic, especially in Africanized honey bee colonies, since many introduced queens are not accepted, and virgin queens are less easily accepted than are mated queens. We(More)
A rationale is presented for the use of a relatively low-altitude (15km) Rayleigh Laser Guide Star to provide partial adaptive optics correction across a large fraction of the sky on the 4.2m William Herschel Telescope. The scientific motivation in relation to the available instrumentation suite is discussed and supported by model performance calculations,(More)
We review off-axis telescope concepts that use unobstructed pupils. Built and prospective telescopes for ground and space astronomy will be presented and discussed. Such concepts offer great advantages in terms of emissivity, throughput, diffraction-limited energy concentration and higher dynamic range. The coronagraphic performance of off-axis telescopes(More)
5490 and is made available as an electronic reprint with permission of SPIE. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of(More)
I review the science case for the Laser Guide Star system being built for the William Herschel Telescope (WHT) on La Palma. When used in combination with the NAOMI Adaptive Optics system and the OASIS visible-wavelength Integral Field Spectrograph, I demonstrate that there are substantial, exciting areas of as-trophysical research in which the WHT can(More)
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