Very little was then known about immunology: antibodies had been identified but their structure remained a mystery.
Although enough was then known about the properties of aluminum to indicate a promising future, the cost of the chemical process for producing the metal was too high to permit widespread use.
— that on August 4, 2011, I.R.S. officials in Washington, who by then knew about the Cincinnati office's targeting of conservative groups, met with the I.R.S.'s chief counsel "so that everyone would have the latest information on the issue".
How, he wondered, can we then know about and refer to them and their properties?
Early in the 19th century, scientists like Adolphe-Théodore Brongniart began collating everything that was then known about fossil plants.
I took "evolutionary developmental biology" as the title for my 1992 book (Hall 1992), which set out to summarize what was then known about the origins of the field, its history, and its role in contributing to the evolutionary process.
For his Nobel lecture, Bohr gave his audience a comprehensive survey of what was then known about the structure of the atom, including the correspondence principle, which he had formulated.
She hadn't then known about help available to women like her, and even if she had, she told NPR, "That's not the mind-set that you're in when you're in that situation.
The book vividly describes the cell's major sub-compartments and what was then known about them.
Although new ways of measuring and categorising natural sciences were developed long ago, very little was then known about the health of populations.
