The aim of the present study was to investigate the effects of different dietary sustained-release microencapsulated sodium butyrate (MSB) products (0 (non-supplement), 1·5 and 3·0 h) for a control or oxidised soyabean oil (SBO) diet on fish production, intestinal mucosal condition, immunity and intestinal bacteria in juvenile common carp (Cyprinus carpio). Dietary MSB increased weight gain and reduced the feed conversion ratio within the control and oxidised SBO groups. Gut mucosa was damaged in the oxidised SBO group fed without MSB, in contrast to a normal appearance found in fish fed the MSB1·5 and MSB3·0 diets in the oxidised SBO group. Microvillus density increased in fish fed the MSB1·5 and MSB3·0 diets in the oxidised SBO group (P,0·001); however, microvillus density was affected by the different pre-fed diets in the midgut (P,0·001) and by the different sustained-release times of MSB in the distal gut (DG) (P¼0·003). The interaction between the pre-fed diets and the sustained-release times of dietary MSB was significant for the relative gene expression levels of gut heat shock protein-70 (HSP70), pro-inflammatory cytokines (IL-1b and TNF-a) and anti-inflammatory cytokines (transforming growth factor-b) within each gut segment, except for HSP70 in the DG and IL-1b in the foregut. Modulation of adherent bacterial communities within each gut segment investigated was not obvious when the common carp were fed the diets with MSB, as similarity coefficients of .0·79 were observed. These results indicated that MSB can be used as a dietary supplement to repair or prevent intestinal damage in carp fed oxidised SBO.Key words: Cyprinus carpio: Microencapsulated sodium butyrate: Oxidised soyabean oil: IntestineThe use of antibiotics as growth promoters is a subject of debate in animal production as well as in feed and food industries. Their application in animal feed creates the possibility of building resistance to antibiotics used against bacterial pathogens in animals and humans (1,2) as well as in fish (3) . In 2006, the European Union banned the use of antibiotics in animal feed as growth promoters (European Parliament and Council Regulation no. 1831/2003). Another issue of concern with fish diets is that lipids are rapidly oxidised during storage due to the high content of PUFA, even though synthetic antioxidants such as butylated hydroxyanisole, butylated hydroxytoluene and tert-butyl hydroquinone are supplemented. Furthermore, some plant extracts are used as feed additives in many countries to retard or prevent oxidative deterioration of oil (4) . The products of lipid oxidation such as SCFA, aldehydes and ketones do not only decrease the nutritive value of the feed but also react with cellular membrane components such as protein and DNA (5) . Several studies have reported † Both authors contributed equally to this work.* Corresponding authors: D. M. Gatlin, email d-gatlin@tamu.edu; Z. Zhou, fax þ86 10 82106054, email zhou_zg@msn.comAbbreviations: C-0, basal diet followed by basal diet; C-1·5, basal...

Colloidal matter with a wide range of materials, sizes, and configurations was built with opto-thermophoretic assembly.

Presented are the development of novel 0D-2D nanohybrids consist of nickel-based bimetal phosphorus trisulfides (Ni 1−x Fe x PS 3 ) nanomosaic that decorated on the surface of MXene nanosheets (denoted as NFPS@MXene). The nanohybrids are obtained through a facile self-assemble process of transition metal layered double hydroxide (TMLDH) on MXene surface; followed by the low temperature in-situ solid-state reaction step. By tuning the Ni:Fe ratio, the as-synthesized NFPS@MXene nanohybrids exhibit excellent activities when tested as electrocatalysts for overall water splitting. Particularly, with the initial Ni:Fe ratio of 7:3, the obtained Ni 0.7 Fe 0.3 PS 3 @MXene nanohybrid reveals low overpotential (282 mV) and Tafel slope (36.5 mV dec -1 ) for oxygen evolution reaction (OER) in 1 m KOH solution. Meanwhile, the Ni 0.9 Fe 0.1 PS 3 @MXene shows low overpotential (196 mV) for hydrogen evolution reaction (HER) in 1 m KOH solution. When integrated them for overall water splitting, the Ni 0.7 Fe 0.3 PS 3 @MXene || Ni 0.9 Fe 0.1 PS 3 @MXene couple shows a low onset potential of 1.42 V and needs only 1.65 V to reach a current density of 10 mA cm -2 , which is better than the all noble metal IrO 2 || Pt/C electrocatalyst (1.71 mV@10 mA cm −2 ). Given the chemical versatility of Ni 1−x Fe x PS 3 and the convenient self-assemble process, the nanohybrids demonstrated in this work are promising for energy conversion applications.

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