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1. Growth performance of Yangzhou geese hatched from eggs with turning angles of 50° or 70° was evaluated in association with serum hormones and somatotrophic gene mRNA expression. 2. Egg turning at 70° significantly (P< 0.05) increased hatchability, gosling quality and hatching weight. Gosling post-hatch body weight, leg and breast muscle weight in the 70° turning group was significantly heavier until 50 d of age. 3. Serum concentrations of GH were significantly higher until 30 d of age in the 70° turning group goslings, and those of IGF-I and T3 were higher from hatching to 50 d of age. 4. The mRNA expression of GHRH, pituitary GH, liver and leg muscle IGF-I were all significantly higher at 1 and 30 d of age after hatch, but not at 70 d after hatch, in the 70° turning group. 5. Egg turning at 70° during incubation improves embryo and gosling quality and growth performance through up-regulation of gene expression and secretion of somatotrophic axis hormones, GHRH, GH and IGF-I, as well as T3. [ABSTRACT FROM AUTHOR]

The significance of fracture face matrix damage in fractured shale gas wells is not clear. A new mathematical model was developed to predict the effect of fracture face matrix damage on productivity of fractured gas wells in shale gas reservoirs. Results of the model analyses were sensitized to reservoir properties and facture face matrix skin properties determined by the fracturing fluid properties and treatment conditions. The authors conclude that fracture face matrix damage is strongly affected by the properties of fracturing fluids. Using the lowest possible leak-off coefficient and spurt-loss coefficient can significantly reduce fracture face matrix damage and retain gas well productivity. [ABSTRACT FROM AUTHOR]

The influence of friction on microforming increased dramatically than macroforming with the miniature of the forming parts. The factors which have great impact on friction coefficient in microsheet forming were studied in this paper by strip drawing test. The specimen material was copper C1100, which was thermally treated at 600°C for 12 h in nitrogen atmosphere. The experiments were carried out at room temperature on a universal testing machine under four kinds of punch roughness, sheet roughness, drawing velocity and lubrication conditions respectively. The results showed that the friction coefficient increased with the increasing punch roughness and sheet roughness, but decreased with the increasing drawing velocity. However, the friction coefficient did not change under different lubrication conditions, which is quite different from macroforming. The reason for this phenomenon was also discussed at the end of this paper. [ABSTRACT FROM AUTHOR]

A plasma metamaterial that exhibits negative refraction in the terahertz region of the spectrum has been demonstrated in the present communication. The plasma metamaterial is an uniaxial anisotropic metamaterial which is a multilayer stack of alternating plasma layer and background material. The negative refraction in the terahertz region of the proposed metamaterial is explored. The effects of the losses in plasma, plasma density, plasma filling factor, and dielectric constant of background material on the critical frequency ω0 and the band width of negative refraction Δω are examined and discussed. [ABSTRACT FROM AUTHOR]

In the present paper, we first show that the plasma injected into the interaction region forms a periodical distribution of the plasma density that is called self-induced density grating and exerts a periodic perturbation on the dielectric constant under two strong counterpropagating waves modulation. In succession, we demonstrate that the self-induced quasi periodic plasma density grating formed by the self-induced distributed feedback possesses the properties of plasma photonic crystal (PPC). Therefore, the formation of PPC by the self-induced quasi periodic plasma density grating is a feasible fabrication scenario for PPC. Based on an equivalent model of the plasma density grating, a dispersion relation is derived, and a simple case is calculated and discussed. [ABSTRACT FROM AUTHOR]