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  • B Wu, E Beitz
  • 2007
The aquaporin protein family generally seems to be designed for the selective passage of water or glycerol. Charged molecules, metal ions and even protons are strictly excluded. Recently, particular aquaporin isoforms were reported to conduct unconventional permeants, i.e., the unpolar gases carbon dioxide and nitric oxide, the polar gas ammonia, the(More)
For the purpose of investigating the evolution of dust aggregates in the early Solar System, we developed two vacuum drop towers in which fragile dust aggregates with sizes up to ~10 cm and porosities up to 70% can be collided. One of the drop towers is primarily used for very low impact speeds down to below 0.01 m/sec and makes use of a double release(More)
To achieve what I believe to be an acceptable. Information Management System, I propose that a set-theoretic view of a data-base be adopted. Most potential data-base users use the language of set-theory in their day to day references to the objects and relationships of their data-bases. Instead of twisting these natural language references to(More)
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