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.

Example Input: Question: Does the tissue Doppler imaging derived post-systolic velocity notch originate at the aortic annulus?
Answer: The AA represents the site of the earliest onset and maximal amplitude of the PSN on the longitudinal velocity curve suggesting its mechanism to be that of an energy release at the instant of the aortic valve closure causing an apically directed acceleration of the myocardium. A substantial number of healthy subjects exhibit a second PSN spike predominantly at the level of the AA. Its mechanism remains to be elucidated.
Example Output: yes

Example Input: Question: Are circulating levels of IL-1beta , a prothrombotic cytokine , elevated in unstable angina versus stable angina?
Answer: Our results suggest that both IL-1beta and IL-6 contribute to the pathogenesis of unstable angina, and that the profile of circulating plasma levels of proinflammatory cytokines differs in unstable angina from that in stable angina. Abbreviated Abstract. Multiple studies support a role for inflammation in the pathogenesis of coronary atherosclerosis and unstable cardiac syndromes. We measured plasma levels of interleukin-1 beta (IL-1beta), tumor necrosis factor alpha (TNF-alpha), and interleukin 6 (IL-6) in patients with stable and unstable coronary syndromes. Levels of IL-1beta and IL-6 were found to be elevated in patients with unstable coronary syndromes. No significant differences were found in the levels of TNF-alpha. Our results suggest that both IL-1beta and IL-6 contribute to the pathogenesis of unstable angina.
Example Output: yes

Example Input: Question: Does fDG uptake heterogeneity in FIGO IIb cervical carcinoma predict pelvic lymph node involvement?
Answer: FDG uptake heterogeneity did not indicate patients with differing prognoses. Apparent heterogeneity differences between clinical groups may be an artifact arising from either the dependence of some image metrics upon other factors such as tumor volume or upon the underlying variations in the patient populations compared.
Example Output:
no