Given a passage with a question and an answer to that question, classify if the answer actually answers the question into 'yes' or 'no'. Output 'yes' if the answer answers the question and output 'no' if the answer does not answer the question.
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Question: Question: Is the dorsal motor nucleus of the vagus an obligatory trigger site of Parkinson 's disease : a critical analysis of alpha-synuclein staging?
Answer: Our results demonstrate a predominant involvement of the SN and NBM in PD but do not support the existence of a medullary induction site of alpha Syn pathology in all PD brains.

Answer: no


Question: Question: Is allocentric but not egocentric orientation impaired during normal aging : an ERP study?
Answer: These results suggest that elderly individuals present with deficits when spatial orientation relies on allocentric representation, and are associated with age-related deficits in spatial attention.

Answer: yes


Question: Question: Is mechanical stress associated with right ventricular response to pulmonary valve replacement in patients with repaired tetralogy of Fallot?
Answer: Computational modeling and right ventricular stress may be used as tools to identify right ventricular function response to pulmonary valve replacement. Large-scale clinical studies are needed to validate these preliminary findings.

Answer:
yes