The phrase "a significantly less aggressive" is correct and usable in written English.
It can be used when comparing the level of aggression of two or more subjects, indicating that one is notably milder than the other.
Example: "The new marketing strategy is a significantly less aggressive approach than our previous campaigns."
Alternatives: "much less confrontational" or "considerably milder".
In conclusion, high mammaglobin expression in breast cancer is associated with a significantly less aggressive tumour phenotype.
Incremental theory group participants, however, assigned their partners almost 40% less hot sauce (Mincremental theory = 24.89 g, SD = 27.13), a significantly less aggressive response, b = −15.19, SE = 7.12, t 88) = −2.13, p <.05, d =.47 (see Figure 2a).
These two procedures gave similar results (Figure 1C, D): workers exposed to CHCs of an alien colony became significantly less aggressive towards freshly killed non-nestmates from that colony, as compared to workers that were exposed to nestmate CHCs (GLMM, least square means comparisons: p<0.0001).
The president's top appointments to the Justice Department and the Federal Trade Commission have a more expansive understanding of antitrust, but one that is significantly less aggressive in many areas than those of their predecessors in the Clinton administration.
In contrast, drivers who gave others the 'benefit of the doubt' endorsed significantly less aggressive driving responses than either of these other two groups, suggesting that this style is protective.
Kruskall-Wallis test shows that drivers' behavior in proximity of pedestrians tends to be statistically significantly less aggressive when their approach velocity is lower, curb-side parking is not allowed, a crosswalk exists, and the number of pedestrians crossing the street is higher.
Examining the influence of good corporate governance structures on tax avoidance, Richardson et al. (2013) provide evidence that companies that use one of the Big 4 auditing firms display significantly less aggressive tax planning.
Our results also showed a significant effect of the season on different indicators, An. gambiae populations in the rainy season were significantly more exophilic and significantly less aggressive than in the dry season.
By contrast, in experiment 2, focal ants that had been exposed to the nest material of the target ant were not significantly less aggressive towards the target relative to controls across all five colony pairs (Figure 1B; GLMM: t132 = 1.07, p = 0.29).
