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.

Ex Input:
Question: Does brivaracetam differentially affect voltage-gated sodium currents without impairing sustained repetitive firing in neurons?
Answer: The lack of effect of BRV on SRF in neurons suggests that the reported inhibition of BRV on VGSC currents does not contribute to its antiepileptic properties.

Ex Output:
yes


Ex Input:
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.

Ex Output:
no


Ex Input:
Question: Are nadir PSA level and time to nadir PSA prognostic factors in patients with metastatic prostate cancer?
Answer: Nadir PSA and time from PADT to nadir were factors that affect both CRPC and overall survival in a cohort of patients with metastatic prostate cancer. Lower nadir PSA level and longer time from PADT to nadir were good for survival and progression.

Ex Output:

yes