The phrase "ascertained definitely" is correct and usable in written English.
It can be used when you want to express that something has been confirmed or established with certainty.
Example: "After thorough investigation, the facts were ascertained definitely, leaving no room for doubt."
Alternatives: "confirmed clearly" or "established definitively."
Larger studies are needed to ascertain more definitely the role of HMGB1 in the development of vascular complications in diabetes.
"The identity of Mrs Simpson's secret lover has now been definitely ascertained.
Finally, in some situations (e.g. cardiac arrest or shock), the exact role of metformin in explaining the degree of lactic acidosis could not be definitely ascertained as these conditions may per se be associated with hyperlactataemia.
The synod said it had ascertained that Metropolitan Volodymyr was definitely too ill to carry out his duties.
To definitely ascertain whether treatment with azacitidine conferred a survival benefit to MDS patients, the large randomized phase III AZA-001 trial was initiated.
Six of these trials, evaluating specific dementia interventions, described their processes in sufficient detail for us to ascertain that they definitely did not assess capacity in any residents.
The enumeration of CD34+COL1 mRNA+ fibrocytes on cytospins of blood leukocytes from normal and asthmatic subjects was previously performed to definitely ascertain if authentic fibrocytes are really present in the peripheral blood [10].
So far Friday, Moscow has rejected direct talks with Ukraine mediated by the West, a notion that Putin's spokesman said "makes us smile"; and blocked international observers from entering Crimea with troops whose specific affiliation was not ascertained but who in any case were definitely not withdrawn to bases.
A total of 53.5% of diagnoses were definitely confirmed by positive histopathology; 38.5% were ascertained by imaging techniques combined with serology, or imaging alone, when obtaining tissue specimens for analysis was not possible.
In contrast, the origin of some of the longest threads seen in very late anaphase is more difficult to ascertain, and it is definitely possible that some of these late persisting threads comprise incompletely replicated DNA or unresolved recombination intermediates (as discussed in Chan et al. 2007).
