This study investigated the growth performance and nutritional composition of scale artificially cultured cuttlefish Sepia pharaonis. Juveniles were cultured in an open-culturing cement pool system for 120 days. The body weight increased from 10.21 AE 1.44 g to 570.71 AE 126.32 g from 50 days old to 170 days old, and the average growth rate was 4.67%. The proximate, amino acid and fatty acid compositions of S. pharaonis muscles were analysed every 40 days to compare the quality. The cultured S. pharaonis were rich in essential amino acids (EAAs), functional amino acids (FAAs), docosahexaenoic acid (DHA) and polyunsaturated fatty acids (PUFAs), which accounted for 32%, 46%, 28% and 54% (dry weight) respectively.Total amino acids (TAAs) and EAAs exhibited a clear distinction between ages, and significant differences were observed among the levels of individual amino acids, including Pro, Ala, Asp and Lys, which were significantly higher at 130-170 days old than at 50 days old (p < 0.05). Although the total saturated fatty acids, monounsaturated fatty acids and PUFAs were statistically similar between ages, C17:0, C22:6 n-3 and PUFAs were higher at 130-170 days old than at 50 days old (p < 0.05). The results indicate that large-scale artificial culture of S. pharaonis can be achieved under the conditions of a cement pool. This study also provides new information regarding the growth performance and nutritional composition of cultured S. pharaonis, which will contribute to the development of aquaculture practices for this species. K E Y W O R D S age, artificial culture, biochemical composition, cuttlefish, growth, Sepia pharaonis wileyonlinelibrary.com/journal/are Aquaculture Research. 2018;49:2788-2798.

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Achieving broadband energy harvesting at low frequencies is a difficult area of research today. To solve the aforementioned problems, herein, a nonlinear sickle‐shaped cantilever beam piezoelectric energy harvester (S‐PEH) for wind energy harvesting is proposed. It has a high‐voltage output in the wind speed range of 5.37–18.23 m s−1. The S‐PEH is consists of a collector and a transducer. The collector converts wind energy into rotating mechanical energy and excites the transducer by means of magnetic coupling, thus realizing the conversion of mechanical energy to electrical energy. The special structure of the transducer's sickle‐shaped cantilever beam type can effectively harvest wind energy in low‐frequency environment and broaden the range of harvesting wind speed in high voltage. The structure and principle of S‐PEH are analyzed by theory and simulation and are experimentally verified. The results show that when the magnet on the rotor is 15 mm away from the magnet of the piezoelectric sheet, the transducer angle is 90°, the load resistance is 100 kΩ, the voltage of the blower is kept at 120 V, and the system has a maximum power of 563 μW. Moreover, it can successfully make low‐power electronics work.

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Herein, an energy harvester relying on the combination of piezoelectric and electromagnetic power generation is developed to increase the power generation and realize the force deformation of the piezoelectric sheets through the interaction between the exciting and mass magnets, thus avoiding mechanical collision and abrasion and improving the operational life span. The theoretical analysis for the magnetic movement, winding moment, and resilience strain is done, and the maximum shift of the rectangular and circular piezoelectric sheets is obtained through simulation. Experimentally, the device achieves the highest output voltage of 28.4 V when there are two exciting magnets and in mutual repulsion with the mass magnet. For an external resistance of 2 kΩ, the device outputs a maximum power of 20.48 mW. The device can convert wind energy from the environment into electricity and power other devices via circuit storage.