Sexual dimorphism in growth has been reported in mandarin fish leading to a desire for monosex populations in aquaculture farming. The neomale individuals which were physiological males with chromosome genotype XX were prepared through sex reversal using 17 alpha-methyltestosterone (17 alpha-MT). Additionally letrozole as an aromatase inhibitor was also employed for sex reversal in economically important teleost species. This study aimed to compare the masculinization effect of 17 alpha-MT and letrozole and then elucidate the mechanisms of natural sex determination. The sex reversal rate of 17 alpha-MT (100 mg/kg feed)and letrozole (200 mg/kg feed) had no significant difference. However, the gonadosomatic index (GSI) of the letrozole administration group was elevated by 93% compared with the 17 alpha-MT group. Through comparative transcriptomics analysis the expression of amh was repressed in the gonad following 17 alpha-MT administration in the adult stage. The plasma estrogen (E2) content and the expression of cyp19a1a gene were elevated in the 17 alpha-MT administration group. These results suggested that 17 alpha-MT administration plays a dual role in both dmrt1 stimulation and estrogen synthesis activation, which was insufficient to fully repress estrogen signaling in 17 alpha-MT neomales. The masculine sex reversal process was more effective with the aromatase inhibitor letrozole. Furthermore, both dmrt1 and amh expression and cooperation could be induced by letrozole treatment. Although the female marker Foxl2 was transcriptionally activated at the juvenile stage during letrozole treatment, its expression was restricted at the adult stage. Collectively, our data and practice suggest that the aromatase inhibitor letrozole is superior to the 17 alpha-MT in the masculine sex reversal of mandarin fish. Suppression of estrogen synthesis was sufficient to induce male determination which in turn induces the cooperation of dmrt1 and amh.

Solar water purification is a promising scheme to relieve the energy crisis and clean water shortages. In order to improve the efficiency of producing water, it is necessary to develop a novel photothermal conversion interface to manage heat loss and boost water evaporation efficiency. Herein, a Janus hydrogel evaporator of powder active carbon (PAC) and Fe3O4 in polyvinyl alcohol (PVA) and polystyrene sulfonate (PSS) cross-link hydrogel, called CFPS, is explored as the light absorber for broadband light absorption and formed a hydrogel network of the multi-hydrophilic group. Its hydrophilic/hydrophobic structure of CFPS is used to regulate heat loss and promote water transport, which can attain lower evaporation enthalpy and a higher evaporation rate. Specifically, the surface temperature of the CFPS can reach around 45 degrees C and 93.4% energy utilization efficiency under 1 sun illumination. In the comparison of the analogous Fe3O4-based evaporator, CFPS has the higher static evaporation rate with 3.43 kg m-2h- 1. Besides, it has great mechanical properties, durability and anticrystallization function, which can be adapted to the water purification scene of wastewater and hypersaline water desalination. This photosensitive magnetic hydrogel evaporator shows potential in the scenarios of wastewater purification and desalination.

Transition metal sulfides are considered as a kind of promising anode for lithium ion batteries due to their high theoretical capacity, but their further development are still greatly hampered by their volume expansion and electrical conductivity problems. Here, hollow spindle Ni-doped Co9S8@ZnS composites are synthesized by a simple two-steps hydrothermal method. The unique hollow structure, multi-component synergistic effect as well as effective ion doping can improve the comprehensive performance. When the as-obtained composites are used for the lithium ion batteries, which exhibit an ultra-long cycle performance. The capacity of 585 mAh/g can be maintained at 0.1 A/g after a long cycling of 1000 cycles. Even when the current density is raised to 1 A/g, the composites exhibit a high reversible discharge capacity of 758 mAh/g after 500 cycles.

The conductivity and stability of materials have always been the main problems hindering the development of lithium-ion battery applications. Here, we successfully construct MnCO3@NiO composites with unique heterogeneous structure via the epitaxial growth of porous NiO nanosheets (thickness: ∼125 nm) on MnCO3 microspheres (diameter: ∼3 μm) to be the anode of lithium-ion batteries. The synergistic effect provided by this special heterogeneous structure effectively improves the electrochemical kinetics, specific surface area as well as structural stability of the composites, finally resulting in predictable enhanced comprehensive electrochemical performance. The electrochemical results show that the MnCO3@NiO composites exhibit a reversible discharge capacity of 624 mA h g-1 at a current density of 1.0 A g-1 up to 300 cycles.

Chinese hydrangea lantern-like Co9S8@MoS2 composites are prepared by a facile solvothermal method. Ultra-thin MoS2 nanosheets as the shells grow tightly and uniformly on the surface of the Co9S8 core. Due to their unique hierarchical core-shell structure and novel morphology, the composites show excellent electrochemical performance as the anode materials of lithium-ion batteries. They can deliver reversible discharge capacities of around 1298, 1150, 1089, 1018 and 941 mA h g-1 at the current densities of 0.1, 0.5, 1, 1.5 and 2.0 A g-1, respectively. Moreover, the Co9S8@MoS2 composites can still maintain a discharge capacity of 1048 mA h g-1 after 300 cycles at a current density of 1.0 A g-1.

Controlling the inherent polysulfide shuttle process has been the key research topic to solve the irreversible capacity loss problem of Li–S battery. By skillfully designing, hierarchical brain coral-like WS2 nanosheets are synthesized. The novel structure is consisted of WS2 nanosheets arrayed along the same crystal plane, which expose a large number of adsorption active sites and enhance the adsorption of polysulfides. At the same time, the multilayer sheet structure has a large specific surface area and increases the sulfur loading. The brain coral-like WS2/S cathode exhibits excellent electrochemical properties, which delivers an initial discharge specific capacity of 1308 mAh g−1 at 0.1 C. And when cycles at 2 C, the discharge specific capacity is maintained at 721 mAh g−1 after 500 cycles, together with a low decay of 0.06% per cycle.

Herein, yolk-double shell Fe3O4@C@C nanospheres (YDS-FCCNs) were designed and synthesized via solvothermal and following heat management. The as-obtained yolk-shell morphology consisted by two parts: one for the Fe3O4@C nanosphere (diameter about 100 nm) as core, and the other for nitrogen-doped carbon (thickness about 50 nm) as the shell. The YDS-FCCNs composite exhibited preeminent cycling stability of 780 mAh/g at 0.5 A/g after 500 cycles, even at higher current density of 2 A/g, it still retained a reversible capacity of 559 mAh/g after 500 cycle. The good electrochemical performance could attribute to the following factors: First, the hierarchical double carbon shell could prevent the agglomeration of the Fe3O4, meanwhile largely enhance the electrical conductivity. Second, the synergistic effects for multilayered structure and atomic doping could improve the comprehensive electrochemical performance. (C) 2020 Elsevier B.V. All rights reserved.

Harvesting and converting renewable solar energy into thermal energy has attracted tremendous attraction due to the high conversion efficiency of the photothermal technique. However, the practical large-scale application of photothermal conversion is hindered by ineffective system designs, complex preparation process and poor mechanical properties. Herein, a facile strategy is applied to assemble Al foil/reduced graphene oxide/Mn3O4 (Al/RGO/Mn3O4) composite film with a few outstanding features, including the broadband absorption, high mechanical strength and scalable production, for photothermal vaporization. The Al/RGO/Mn(3)O(4 )composite film prepared by a spontaneously fabricating method can efficiently collect and convert the ubiquitous solar energy into steam, demonstrating a evaporation rate of 1.65 kg m(-2) h(-1) under one sun and an excellent stability for desalination. The reducing/assembling strategy at room temperature may provide potential opportunity for practical large-scale photothermal applications. (C) 2019 Elsevier Ltd. All rights reserved.

The mandarin fish Siniperca chuatsi is a historically important aquaculture species in China and exhibits sexually dimorphic growth. However, sex determination of this fish remains unclear so far. In this study, we induced meiotic gynogenesis in S. chuatsi using irradiated heterologous sperm from spotted mandarin fish (Siniperca scherzeri) to uncover its mechanism of sex determination. Up to 7.52% diploid progeny were obtained among three gynogenetic families in this study. Molecular analysis of female and male donors and sampled young gynogens by seven microsatellite loci further confirmed no genetic contributions from the ‘father’ S. scherzeri. After 8 months of culture, external morphology of adult fish showed that all gynogens were cloned from their mothers. Gonads of the gynogenetic progeny were examined by histological observations and the sexing results showed that they were almost 100% females, strongly supporting an assumption of female homogamety in mandarin fish. By this study, we obtained pure lines of S. chuatsi and elucidated its genetic mechanism of sex determination, providing a basis for possible sex control breeding in this species.

Hierarchical LiNi0.5Mn1.5O4 (LNMO) microspheres were prepared via a hydrothermal method followed by program controlled temperature calcination. The as-obtained LNMO microspheres (diameter: similar to 5 mu m) which were assembled with submicron nanorices particles (length: similar to 500 nm) (R-LNMO) could combine the superiority of the both nanosized and microsized structure, enhancing rates performance. The result indicated that R-LNMO exhibited discharge capacities of 141 mAh g(-1) after 200 cycles at 2 C, together with the capacity retention of 95.2%. Besides, R-LNMO could deliver capacities of 147, 141, 137, 128, 120, 114 mAh g(-1) at rates of 0.1, 2, 5, 10, 15 and 20 C, showing prospectively superior rates performance. (C) 2018 Elsevier B.V. All rights reserved.

In order to maximize the output, minimize the waste produced by the fish, and develop nutritionally adequate diets, the digestibility and nutritional value of feed ingredients were evaluated. The objective of this study was to determine apparent digestibility coefficients (ADCs) of dry matter, crude protein, gross energy, phosphorus, and amino acids in feed ingredients for mandarin fish, Siniperca chuatsi with initial average body weight of 31.27 +/- 1.64 g. Nine experimental ingredients including white fish meal (WFM), meat and bone meal (MBM), maggot meal (MGM), soybean meal (SBM), fermented soybean meal (FSBM), peanut meal (PNM), corn gluten meal (CGM), cottonseed meal (CSM), and rapeseed meal (RSM) were added to reference diet containing 53% (WFM) at two levels of 15 and 30%. The ADCs of dry matter at the level of 30% were higher than those at the level of 15% in mandarin fish fed with the diet with WFM. In addition, the highest ADCs of dry matter (80.96%) was observed in fish fed with the diet with WFM at the content level of 30%, followed by lower ADC of the ingredients with FSBM, MGM, CGM, SBM, MBM, PNM, CSM, and RSM. However, the ADCs of dry matter in mandarin fish fed with the diet at the level of 15% were higher than those at the level of 30% in MBM, CGM and PNM. The results indicated that ADCs of the experimental ingredients were significantly affected by the ingredient type and the content level. The highest digestion of protein (88.90%) was also observed in WFM at the level of 30%, followed by FSBM (83.93%) and MGM (82.59%) at 30% content level, MGM and FSBM at 15% content level and CGM at 30% content level. Lipid ADCs of WFM, MBM, SBM, FSBM, CGM and CSM ranged from 83.96 to 93.25%, indicating that the lipid of these ingredients was efficiently digested by mandarin fish. The highest digestibility coefficient of energy (88.74%) was registered in WFM at 30% content level, followed by MGM at 30% content level, and the lowest digestibility coefficient of energy (49.24%) was recorded in RSM at 30% content level (P < 0.05). In addition, the apparent digestibility of phosphorus in animal feeds and plant feeds ranged from 35.75 to 63.91% and from 42.21 to 66.77%, respectively. Amino acids digestibility followed a similar pattern to those of ADCs of protein in the animal feeds. Amino acids digestibility in WFM and MGM were generally higher than those in MBM among all the plant feeds. The digestibility of amino acids in FSBM, SBM, and CGM were higher than those in RSM and CSM. In conclusion, these data provide more precise information concerning nutrient and energy utilization of Siniperca chuatsi and will allow ingredient substitutions in practical feed based on levels of available nutrients. Based on the current findings, we propose that FSBM, MGM, SBM, and CGM could be considered for incorporation into formulated diets for mandarin fish.