Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.

Ex Input:
Many patients with restless legs syndrome (Willis-Ekbom disease) complain of burning sensations in their feet associated with the desire to move, such that they seek cooler environments. This pilot study aimed to characterise the microvascular skin changes in 12 patients with restless legs syndrome compared with 12 age- and sex-matched controls. Patients with moderate or severe restless legs syndrome and controls underwent detailed thermovascular assessment in a controlled temperature room at three different stages (normothermic phase 23C, hot phase 30C, cold phase 18C). Microvascular activity was recorded during all phases by bilateral great toe laser-Doppler flowmetry and also by whole-body thermography. Patient and control measurements were compared. The study protocol was well tolerated. Parameters extracted from the laser-Doppler flowmetry measurements were used to model a logistic function using binary logistic regression. This demonstrated a statistically significant difference between patients with restless legs syndrome and healthy controls (P<0.001). Visual inspection of the body thermography image sequences showed increased lower limb movement in patients with restless legs syndrome patients compared with controls. Thermography analysis also showed significant differences between foot temperatures in patients with restless legs syndrome compared with controls during the hot phase (P=0.011). Notably, patients with restless legs syndrome had more uniform foot temperatures, whereas controls had a wider variability in surface temperature across the feet. This novel study demonstrates impaired microvascular circulation in patients with restless legs syndrome in comparison to matched controls and a potential mechanism for the sensation of burning feet. The protocol also provides an experimental paradigm to test therapeutic interventions for the future.

Ex Output:
Willis-Ekbom disease is also known as?


Ex Input:
Lu Fang is a fictional character in Water Margin, one of the Four Great Classical Novels of Chinese literature.

Ex Output:
To which fictional work does Lü Fang belong in?


Ex Input:
Sharpe's Challenge is a British TV film from 2006, usually shown in two parts, which is part of an ITV series based on Bernard Cornwell's historical fiction novels about the English soldier Richard Sharpe during the Napoleonic Wars.

Ex Output:

Which is the basis of Sharpe's Challenge?