The phrase "an arca" is not correct in standard written English.
It appears to be a misspelling or misusage, as "arca" is not a recognized English word.
Example: "I found an arca in the attic." (This would be incorrect unless "arca" is defined in context.)
Alternatives: "a box" or "a chest."
A month later, Childress saw Bowyer racing at an ARCA race in North Carolina.
Norfleet had indicated that she planned to race in an Arca event at Daytona International Speedway last month.
The cameras have chronicled Patrick's every move in her first week in stock cars, beginning with her initiation last Saturday when she ran an ARCA race here.
Patrick raised expectations with a promising sixth-place finish in an ARCA series race here Feb. 6, inspiring the decision to attempt the Nationwide race.
Because Norfleet had not completed the evaluation to be allowed to race, he said, "it would be inaccurate for her to say that she's an Arca driver".
In her second attempt in an ARCA race, in the lower levels of stock-car racing, Crocker finished seventh yesterday in a field of 40 cars in the Hantz Group 200 at Michigan International Speedway.
Many down-regulated genes coded for proteins involved in anaerobic metabolism, some of which are known to be regulated by one or both of the two important anaerobic regulators, hlyX and anoxic redox control protein A (arcA) [ 46, 61].
Candidate sites are shown by letters: F – Fnr sites; A – ArcA sites, N – NarP sites; conserved sites are shown by capital letters, non-conserved ones by lower-case letters (for details see "Methods").
By identifying an ArcA-binding motif in close proximity to arcA, the in silico analysis reinforces that ArcA represses its own expression through a direct-control mechanism.
Similarly, S. oneidensis ArcA may acquire controls over new genes once an ArcA-binding site emerged in their promoter regions through evolution.
Also, we have previously shown that a constitutively active arcB allele (the upstream activator of ArcA) results in an ArcA-dependent lifespan extension [ 5].
