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This study aimed to describe and compare the morphological characteristics of saccular otoliths (sagittae) in the protandrous hermaphrodite Sarpa salpa and the synchronous hermaphrodite Serranus scriba collected from the Bizerte site located in northwestern Tunisia, and to examine the effect of hermaphroditism type on the otolith shape and size at the inter- and intraspecific levels, using elliptical Fourier analysis. At the interspecific level, a significant bilateral asymmetry in shape was observed between the left and right otoliths. At the intraspecific level, a significant bilateral asymmetry in shape was detected between the left and right otoliths only in S. scriba. Discriminant function analysis (DFA) produced two separate main groups corresponding to the two species, and intrasexually differentiated between left and right otoliths in S. salpa. In addition, a significant bilateral asymmetry was found in Lo, Wo, Ao, and Po in S. salpa and in Po only in synchronous S. scriba. Thus, protandrous hermaphroditism did not affect otolith shape in S. salpa, but showed an apparent bilateral asymmetry in otolith size. However, synchronous hermaphroditism exhibited a significant bilateral asymmetry in otolith shape and Po only in S. scriba. The causes of this significant inter- and intraspecific bilateral asymmetry observed in otolith shape and size were discussed.

We study the following problem: given a regular symmetric form (linear functional) v, find all the regular symmetric forms u which satisfy the equation x 3 u = λ x v , λ ∈ C − { 0 }. We give the second-order recurrence relation of the orthogonal polynomial sequence with respect to u. Moreover, in the case where v is a semi-classical form of class s, we show that u is semi-classical and its class is analyzed in term of the class of v. An example is highlighted. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Daytime melatonin ingestion is known to induce sleep at rest, which may affect arousal and vigilance. Physical exercise is known to produce an increase in core temperature and circulating cortisol which can enhance arousal and vigilance. The effect of sub- maximal exercise on vigilance and arousal following acute melatonin ingestion has not yet been studied. The present study aimed at investigating the effect of submaximal exercise on vigilance and arousal following daytime melatonin ingestion. PATIENTS AND METHODS: Eight physical education students undertook 45 min of submaximal exercise (at 60% of maximal aerobic speed) on a treadmill after melatonin-(6 mg) or placebo ingestion, in a randomized and counterbalanced order. RESULTS: Heart rate (HR), rectal temperature (Tre ), felt arousal scale (FAS), and thermal sensations (TS) were recorded at baseline (pre-exercise), immediately after exercise (post-exercise), and after 30 min of recovery (30 min post-exercise). Blood was sampled for lactate and cortisol. At 30 min post-exercise, the Tre, HR, blood pressure, lactate, FAS, and TS were measured. The participants performed vigilance tests pre-exercise, post-exercise and 30 min post-exercise. Daytime melatonin ingestion affected arousal and vigilance in the pre-exercise period (p < 0.05) but had no effect on Tre, HR, blood pressure, lactate, TS, arousal, and vigilance measured 30 min post-exercise (p > 0.05). CONCLUSIONS: The negative effects of melatonin ingestion on vigilance and arousal vanished after a 45 min of submaximal exercise. The hypnotic effect of melatonin observed in the pre-exercise dissipated in the post-exercise period, possibly due to the significant elevation of Tre, HR, and cortisol at the end of submaximal exercise. [ABSTRACT FROM AUTHOR]