If such a population exists, the challenges will be to find pathological or biological markers to identify it, and to research interventions that will make the remaining lung tumour population behave in the same benign manner.
To make this technique reproducible, there still exist the challenge of proper calibration and validation of such mechanical assessment.
While the need for real-time news and updates has increased to a point where screens, checks, and balances almost cease to exist, the challenge has now become how to achieve a balance.
While technology with the potential to reduce work time exists, the political challenge of a working population with time on its hands makes the ruling class unwilling to realise this potential.
Therefore, there exists the great challenge of reducing the incidences of distant metastases and secondary malignant disease among these patients.
The groundwork for a wholistic view of nature already existed, the Romantics challenged the clockwork model; in the United States, worry about the misuse of nature went back as far as Fenimore Cooper and Thoreau.
For each task performed by Life Support Systems (LSS) a great multitude of sub-system concepts exist and the challenge is to find the optimal combination of sub-systems for a given mission scenario.
Some theoretical work exists on the challenges facing reformers, who tend, by definition, not to be favoured by the status quo and its institutions (Swank 2002; Oliver 2006).
Research exists examining the challenges of delivering lifestyle behaviour change initiatives in practice.
