TASK DEFINITION: Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.
PROBLEM: Context: Restless leg syndrome (RLS) is a sensorimotor disorder. Clinical studies have implicated the dopaminergic system in RLS, while others have suggested that it is associated with insufficient levels of brain iron. To date, alterations in brain iron status have been demonstrated but, despite suggestions from the clinical literature, there have been no consistent findings documenting a dopaminergic abnormality in RLS brain tissue. In this study, the substantia nigra and putamen were obtained at autopsy from individuals with primary RLS and a neurologically normal control group. A quantitative profile of the dopaminergic system was obtained. Additional assays were performed on a catecholaminergic cell line and animal models of iron deficiency. RLS tissue, compared with controls, showed a significant decrease in D2R in the putamen that correlated with severity of the RLS. RLS also showed significant increases in tyrosine hydroxylase (TH) in the substantia nigra, compared with the controls, but not in the putamen. Both TH and phosphorylated (active) TH were significantly increased in both the substantia nigra and putamen. There were no significant differences in either the putamen or nigra for dopamine receptor 1, dopamine transporters or for VMAT. Significant increases in TH and phosphorylated TH were also seen in both the animal and cell models of iron insufficiency similar to that from the RLS autopsy data. For the first time, a clear indication of dopamine pathology in RLS is revealed in this autopsy study. The results suggest cellular regulation of dopamine production that closely matches the data from cellular and animal iron insufficiency models. The results are consistent with the hypothesis that a primary iron insufficiency produces a dopaminergic abnormality characterized as an overly activated dopaminergic system as part of the RLS pathology. 
 Question: Which deficiency is the cause of restless leg syndrome?

SOLUTION: iron

PROBLEM: Context: The Caste War of Yucatan was a conflict that lasted from 1847 to 1901. It began with the revolt of native Maya people led by Maya chiefs Jacinto Pat and Cecilio Chi, against the population of European descent called "Yucatecos", who had political and economic control. A lengthy war ensued between the Yucateco forces in the north-west of the Yucatan and the independent Maya in the south-east. It officially ended with the occupation of the Maya capital of Chan Santa Cruz by the Mexican army in 1901, although skirmishes with villages and small settlements that refused to acknowledge Mexican control continued for over another decade. Adam Jones wrote: "This ferocious race war featured genocidal atrocities on both sides, with up to 200,000 killed." Because of the conflict, on November 24, 1902, Yucatan had a second territorial division when Porfirio Diaz decreed the creation of the Federal Territory of Quintana Roo, with capital in the port of Payo Obispo . In little more than half a century, Yucatan lost more than two thirds of its original territory. 
 Question: Who had control of the area after 1901?

SOLUTION: mexican army

PROBLEM: Context: Week 8 saw the Bears return to Soldier Field to play the San Francisco 49ers. Prior to the game, Lovie Smith announced that the Bears would don their alternative orange jerseys to commemorate the upcoming Halloween holiday, and asked Bear fans to wear orange clothing to create an "orange swarm" at Soldier Field. The Bears' 41 point first half tied the franchise record for most points scored in one half, the other game being the 1940 NFL Championship, where the Bears defeated the Washington Redskins 73-0. 
 Question: Who was winning at halftime?

SOLUTION:
the bears