They were the first scientific research team to substantively challenge the methodology of the practice, and the first to conduct research using human cadavers as opposed to animal matter.
He has not tried to find the everyday limits of the various restrictions, or challenged them, substantively, in less hectic circumstances.
They are also serious charges substantively, because they challenge the performance of America's intelligence services and raise questions about whether war in Iraq was justified.
In all cases, however, mentoring entails communicating substantively, supporting significantly, and challenging appropriately.
"Once again, House Republicans have chosen to engage in politics rather than substantively address the challenges that face the American people," said Representative Steny H. Hoyer of Maryland, the House Democratic leader.
On issues like trade and interventionist foreign policy, a right-wing candidate like Trump could credibly challenge Clinton or at least prompt voters to ask, "Why is this sort of stuff good for Americans?" No matter Clinton's response, that debate would be a chance to talk, substantively, about the US economy, and America's place in the world.
One challenging aspect of the study of stress pollution interactions is the distinct chronicity of stress, because acute and chronic stress produce substantively different physiologic sequelae.
If finding a biomarker can be compared to finding a 'needle in a haystack', then big data promises more needles, but with the challenge of substantively more haystacks.
In that, Hazon has become a leader in substantively connecting ancient traditions to contemporary challenges.
Drug-related side effects also create relational challenges for cardiologists, as side effects may substantively affect the patient's willingness to engage in the treatment.
