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.

Q: Question: Does interaction of programmed death-1 and programmed death-1 ligand-1 contribute to testicular immune privilege?
Answer: The constitutive expression of PD-L1 in the testis is an important mechanism underlying testicular immune privilege and long-term survival of intratesticular islet allografts.

A: yes
****
Q: Question: Is the absolute nucleated red blood cell ( aNRBC ) count at birth an indicator for retinopathy of prematurity ( ROP )?
Answer: We are unable to support the previously reported relationship of aNRBCs with ROP. Our population was three times larger, had higher aNRBCs and less retinopathy than previously reported. A biological principle of cause and effect or predisposition to ROP as reflected by aNRBCs should have been easier for us to demonstrate, if it existed.

A: no
****
Q: Question: Are explosive Training and Heavy Weight Training Effective for Improving Running Economy in Endurance Athletes : A Systematic Review and Meta-Analysis?
Answer: Explosive training and heavy weight training are effective concurrent training methods aiming to improve RE within a few weeks. However, long-term training programs seem to be necessary when the largest possible improvement in RE is desired.

A:
yes
****