[Current knowledge on the genetic factors involved in moyamoya disease].

Moyamoya disease (MMD) is characterized by progressive stenosis and occlusion of the terminal portion of the bilateral carotid arteries as well as arterial collateral vessels. The etiology of MMD, however, remains unknown. Several pieces of evidence suggest the involvement of genetic factors in MMD: over 10% of MMD patients have affected blood relatives; concordance in the affection status has been proven in 80% of identical twins; and there is an ethnic predisposition to MMD, the incidence of the disease being the highest in the Asian population. With regard to genetic factor (s), transmission of MMD does not follow the classic Mendelian law, i.e., skipping of a generation and discordance in identical twins, thereby indicating that genetic influence is likely to determine the susceptibility to MMD. This study aimed to overview the recent findings related to the genetic determinants in MMD and to provide research perspectives for the next decade. Pathophysiological investigations at molecular levels have uncovered the upregulation of various growth and stress response factors that are associated with angiogenesis in occlusive cerebral arteries

A Decision Analysis Approach to Multiple-Choice Examinations

We present a decision analysis approach to the problems faced by people subject to multiple-choice examinations, as often encountered in their education, in looking for a job, or in getting a driving permit. From the candidate’s viewpoint, each question in this form of examination is a decision problem, where the decision space depends on the examination rules and the expected utility is some function of the expected score. We analyse this problem for the two basic situations which occur in practice, namely when the candidate wants to maximize his or her expected score, and when he or she wants to maximize the probability of obtaining the minimum grade required to pass, and we derive the corresponding optimal strategies. We argue that for multiple-choice examinations to be fair, candidates should be required to provide a probability distribution over the possible answers to each question, rather than merely marking the answers judged to be more likely; we then discuss the appropriate scoring rules and the corresponding optimal strategies. As an interesting byproduct, we deduce some illuminating consequences on the scoring procedures of multiple-choice examinations, as they are currently performed. Keywords