"a decrease in activity" is correct and usable in written English.
This phrase can be used to describe a situation in which there is a reduction or slowing down of activity. For example, "We have seen a decrease in activity in the housing market over the last year."
Phosphorylation at this site causes a decrease in activity at low concentrations of the allosteric activator glucose-6-phosphate (Skurat et al., 1994).
On the contrary, subtilisin A, which was used as a control, did not show NaCl-activated characteristics as indicated by a decrease in activity with increasing concentration of NaCl as shown in Figure 5c (square, solid line).
Similarly, we define repetition suppression as any region that is active during stimulus encoding and shows a "decrease" in activity (relative to encoding) upon stimulus repetition.
51 In this cohort, men who became less active over 10 years, as indicated by a decrease in activity of more than 60 minutes per day, had a 2.5 times higher risk for cognitive decline.
Interestingly, the accumulation of Aβ is also shown to activate BACE1 expression (Piccini et al., 2012) along with a decrease in activity of UPS (Almeida et al., 2006).
Financial firms, health care companies and tourism-related businesses reported a decrease in activity.
Surveys of businesses are also gloomier, signalling a decrease in activity across services, manufacturing and construction since the referendum on 23 June.
Previous studies had revealed that the suppression of memories is linked to a decrease in activity in the hippocampus - the area of the brain involved with making new memories and retrieving old ones.
A decrease in activity was observed at the two measuring points on day 9.
Ageing the initial precipitate led to a decrease in activity and also decreased the selectivity towards hydrocarbons.
The BVMO4 from Dietzia sp. D5 also revealed a decrease in activity in the series of 2-, 3- and 4-methylcylohexanones by spectrophotometric measurements (Bisagni et al. 2014a).
