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The homeostasis dysfunctions caused by cold stress remain a threat to intestinal health, particularly for young broiler chickens. We hypothesized that adenosine monophosphate-activated protein kinase (AMPK) was involved in the regulation of cold stress on intestinal health. This study aimed to examine the effect of cold stress for 72 h on growth performance, serum biochemistry, intestinal barrier molecules, and AMPK in broilers. A total of 144 10-day-old male Arbor Acres broilers were subjected to temperature treatments (control 28 ± 1 °C vs cold stress 16 ± 1 °C) for 72 h. Growth performance was monitored, serum was collected for the analysis of physiological parameters, and jejunal mucosa was sampled for the determination of tight junction (TJ) proteins, heat shock proteins, and AMPK signaling molecules. Results showed that 72 h cold treatment reduced average BW gain and increased the feed conversion ratio of the broilers (P 0.05). In conclusion, cold stress significantly reduced the growth performance of broiler chickens. The intestinal barrier function might be impaired, and enhanced bacterial translocation might occur. The unregulated gene expression of TJ proteins implied the remodeling of intestinal barrier. The change of AMPK suggested the possible relationship between intestinal energy metabolism and barrier function under cold stress.

The lattice parameters, vacancy formation energies, elastic properties, Vickers hardness and electronic structure of ReB2 with lower concentration of boron vacancy are studied using first-principles approach. The lattice parameters and unit-cell volume of ReB2 with boron vacancy rapidly decrease as boron vacancy concentration increase. The calculated vacancy formation energies show that the ReB2 are more stable than that of system with boron vacancy. With increasing boron vacancy, the bulk modulus, shear modulus, Young modulus and Vickers hardness gradually decrease and the boron vacancy results in mechanical transition from brittleness to ductility, which are in good agreement with experimental results. The decreases of elastic modulus and Vickers hardness are originated from the weak hybridization between Re atoms and B atoms in boron vacancy region and forms the weak Re–B bonds and B–B covalent bonds.

We systematically investigate the structural and field emission properties of alkali metal atoms adsorbed on graphene using first-principles density-functional theoretical calculations. The calculated results indicate that the center of the hexagonal ring of graphene is the most stable adsorption site, and the alkali metal atom can stay stably on graphene by donating their charges to graphene, which results in the redistribution of the Mulliken charges on graphene. Also, we explore the effects of alkali metal atom adsorption on the field emission properties of graphene, in which the magnitude of the ionization potential of graphene becomes smaller and the Fermi level increases after adsorption. Moreover, the Cs adsorption on graphene is believed to be the best choice for enhancing the field emission properties. The mechanism of the enhanced field emission has been analyzed in terms of the modification of the density of states and the band structures caused by the adsorption. Our findings suggest that graphene can be applied as field emission electron source material, and the adsorption of alkali metal atoms can improve its emission performance, which will be helpful in the design of functionalized graphene electronic devices.

Calculations of the triple differential cross section (TDCS) for electron impact ionization of the Ar (3s) orbital in a coplanar asymmetric geometry, using modified distorted wave Born approximation (DWBA) methods, are reported. The role of the polarization effect in ( e , 2 e ) collisions of Ar (3s) is considered in the calculations, and the calculated results show that the polarization potential is quite important.

The adoption of liquefied petroleum gas vehicles is strongly linked to the break-even distance at which they have the same costs as conventional cars, with very limited market penetration at break-even distances above 40,000 km. Hydrogen vehicles are predicted to have costs by 2030 that should give them a break-even distance of less than this critical level. It will be necessary to ensure that there are sufficient refuelling stations for hydrogen to be a convenient choice for drivers. While additional LPG stations have led to increases in vehicle numbers, and increases in vehicles have been followed by greater numbers of refuelling stations, these effects are too small to give self-sustaining growth. Supportive policies for both vehicles and refuelling stations will be required.

The preparation of BH-1 magnetic liquid is given. It involves three major steps: formation and washing of Fe 3 O 4 , dispersion of Fe 3 O 4 from water phase into oil phase by using oleic acid, and heating of gel-like Fe 3 O 4 aggregate at constant temperature to become BH-1 magnetic liquid. Some properties of BH-1 magnetic liquid have been measured. BH-1 magnetic liquid has a high saturation magnetization and low vapor pressure at room temperature and is stable in performance. It has been used satisfactorily by the 6th research section of BIAA.