Precocious puberty is one of the major constraints to the further development of Chinese mitten crab (Eriocheir sinensis) farming industry. Although dietary phospholipids (PL) and highly unsaturated fatty acids (HUFA) supplementation have been shown to enhance the growth of larval E. sinensis in other studies, it is still unknown whether this also leads to a higher precocity rate for juvenile E. sinensis. This study was conducted to investigate the e¡ects of dietary PL and HUFA on precocity, survival, growth and hepatic lipid composition of juvenile E. sinensis. Two diets were formulated with PL [3.95% dry weight (DW)] and HUFA (0.98% DW) supplementation (diet A) and without PL and HUFA supplementation (diet B) and fed to juvenile E. sinensis. Although dietary PL and HUFA levels did not signi¢cantly a¡ect the survival and growth performance of juvenile E. sinensis, compared with crabs fed diet A, a higher precocity rate was found among juvenile E. sinensis fed diet B (P 5 0.051). A higher total lipid content, but sig-ni¢cantly lower levels of HUFA and PL (Po0.05) were found in the hepatopancreas of crabs fed diet B than in those fed diet A. Meanwhile, the precocious females had signi¢cantly lower hepatosomatic index , arachidonic acid (20:4n-6), eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3) contents in their hepatopancreas when compared with that of the normal immature juveniles (Po0.05). The results suggest that the occurrence of precocious puberty among farmed juvenile E. sinensis could be reduced by the inclusion of appropriate level of dietary PL and HUFA. Ã Vitamin mix: 1kg of diet contained vitamin A 10 000 IU; vitamin D 2500 IU; vitamin K 64 mg; thiamin 60 mg; ribo£avin 250 mg; pyridoxine 60 mg; a-tocopherol acetate 500 mg; L-ascorbic acid 4.5 g; calcium panthothenic 240 mg; niacin 60 mg; folic acid 12 mg; biotin 50 mg; cyanocobalamine 4 mg. wMineral mix: 1kg of diet contained Ca(H 2 PO 4 ) 2 10 g; MgSO 4 Á 7H 2 O 2.4 g; KCl 4.5 g; NaCl 2.1g; FeSO 4 Á H 2 O 155 mg; CuSO 4 Á 5H 2 O 40 mg; ZnSO 4 Á H 2 O 80 mg; MnSO 4 Á H 2 O 30 mg; KI 11.7 mg; CoCl 2 Á 6H 2 O 4.8 mg; Na 2 SeO 3 2.4 mg. Bold highlights the level di¡erence between two diets. Aquaculture Research, 2011, 42, 457^468 Dietary PL and HUFA on the precocity of juvenile Eriocheir sinensis X Wu et al. r

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Measuring metabolite patterns and antioxidant ability is vital to understanding the physiological and molecular responses of plants under salinity. A morphological analysis of five rapeseed cultivars showed that Yangyou 9 and Zhongshuang 11 were the most salt-tolerant and -sensitive, respectively. In Yangyou 9, the reactive oxygen species (ROS) level and malondialdehyde (MDA) content were minimized by the activation of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) for scavenging of over-accumulated ROS under salinity stress. Furthermore, Yangyou 9 showed a significantly higher positive correlation with photosynthetic pigments, osmolyte accumulation, and an adjusted Na+/K+ ratio to improve salt tolerance compared to Zhongshuang 11. Out of 332 compounds identified in the metabolic profile, 225 metabolites were filtrated according to p < 0.05, and 47 metabolites responded to salt stress within tolerant and sensitive cultivars during the studied time, whereas 16 and 9 metabolic compounds accumulated during 12 and 24 h, respectively, in Yangyou 9 after being sown in salt treatment, including fatty acids, amino acids, and flavonoids. These metabolites are relevant to metabolic pathways (amino acid, sucrose, flavonoid metabolism, and tricarboxylic acid cycle (TCA), which accumulated as a response to salinity stress. Thus, Yangyou 9, as a tolerant cultivar, showed improved antioxidant enzyme activity and higher metabolite accumulation, which enhances its tolerance against salinity. This work aids in elucidating the essential cellular metabolic changes in response to salt stress in rapeseed cultivars during seed germination. Meanwhile, the identified metabolites can act as biomarkers to characterize plant performance in breeding programs under salt stress. This comprehensive study of the metabolomics and antioxidant activities of Brassica napus L. during the early seedling stage is of great reference value for plant breeders to develop salt-tolerant rapeseed cultivars.

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In this work, hydroquinone resin was used to grow carbon nanotubes directly on Ni foam. The composites were obtained via a simple carbonization method, which avoids using the explosive gaseous carbon precursors that are usually applied in the chemical vapor deposition method. When evaluated as cathode for Li-O2 batteries, the binder-free structure showed enhanced ORR/OER activities, thus giving a high rate capability (12690 mAh g(-1) at 200 mA g(-1) and 3999 mAh g(-1) at 2000 mA g(-1)) and outstanding long-term cycling stability (capacity limited 2000 mAh g(-1), 110 cycles at 200 mA g(-1)). The excellent battery performance provides new insights into designing a low-cost and high-efficiency cathode for Li-O2 batteries.

Rapeseed is a valuable oil crop due to its high nutritious value and ample oil content. The current study provides a comparative analysis of 24 cultivars to better understand the performance and predict the adaptative mechanisms of drought-tolerant and drought-sensitive cultivars based on germination and morphophysiological traits during the early seedling stage using PEG-6000 simulated drought conditions. JYZ 158 and FY 520 (tolerant cultivars) and YG 2009 and NZ 1838 (sensitive cultivars) were selected to further explore the role of osmolytes and enzymatic activity in improving drought tolerance. This investigation illustrated that drought stress negatively influenced all studied cultivars; however, the degree of influence was different for each cultivar, suggesting their different potential for drought tolerance. Moreover, enzymatic and osmoregulatory mechanisms were highly efficient in tolerant cultivars compared to sensitive cultivars. Additionally, tolerant cultivars showed higher chlorophyll and lower malondialdehyde (MDA) contents versus sensitive cultivars under drought stress conditions. Higher drought tolerance coincided with higher enzymatic activity and osmolyte content. This work showed that JYZ 158 and FY 520 cultivars had higher drought tolerance, and might be a significant germplasm resource for breeding programs developing drought-tolerant rapeseed.

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