Sentence examples for a challenge to define from inspiring English sources

If ever there was a challenge to define the word show-stopper, then this episode's brief to create a religieuse a l'ancienne is it.

The effect of 'normal' human aging on innate and adaptive immunity has been a challenge to define.

As in any other non-pharmacological treatment trial is it always a challenge to define a proper control group.

In the absence of such data, it is a challenge to define the proper indications for PAC use.

It remains a challenge to define how the effects identified in this study can be more systematically addressed in future test evaluations.

Indeed, it is a challenge to define the border line between direct and indirect caspase activation, considering the complex network of signaling that often proceeds rapidly, once initiated, with multiple complex feedback mechanisms.

It might be a bit of a political challenge to define happiness as a legitimate policy objective.

It is a matter of semantics as well as a great challenge to define a true negative example when it comes to mature miRNAs.

Clinical engineering faces today a great challenge to define the basic requirements a person must attend to be called clinical engineer.

Although we all feel we intuitively know what forgiveness is, it has proven to be a theoretical challenge to define it.

It is a real challenge to define and to design diagnostics systems considering the constraints imposed by these service systems.