Before development of a new NAAQS, the U.S. EPA must develop air quality criteria for each chemical, detailing the scientific rationale for regulation.
Pyridine occurs in coal tar, its principal source before development of a synthesis based on acetaldehyde and ammonia.
A couple of key questions remain to be answered before development of a final algorithm.
The T-DNA insertion mutant of SNB generates additional bracts (equivalent to rudimentary glumes) before development of a floret and also shows defects in floral organ development [ 24].
They have also speculated that Tregs may develop from DN2 or DN3 stage T cells separately before development of naïve cells.
Wheel-lock guns, in which a spring-driven, serrated wheel rotated against a piece of pyrite, were used before development of the flintlock.
Cervical cancer can be prevented by HPV-vaccination, screening and treatment of precancer before development of cervical cancer.
At 2 weeks (before development of ACF), there were marked changes in a number of 4D-ELF signatures.
The prognosis is better if treatment is instituted early before development of hypercalcemia and hyperphosphatemia enables tissue mineralization to progress.
Rocksteady began conceiving ideas for a possible sequel, which became Batman: Arkham City, approximately seven months before development of Arkham Asylum was completed.
