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Abstract: The ingredients’ particle size and dietary viscosity may alter digestion, performance and faecal waste management of fish. This study aimed to assess the effect of grinding screen sizes of feed ingredients and dietary viscosity on digestibility, faecal waste and performance of striped catfish (Pangasianodon hypophthalmus, Sauvage, 1878). The experiment had a 2 × 3 factorial‐design: two feed mesh particle sizes, by grinding ingredient mixtures at two screen sizes (0.8 versus 1.0 mm); and three dietary viscosity levels, created by exchanging carboxymethylcellulose by guar gum (GG) (0, 3 and 6 g of GG/kg of diet). Six diets were assigned to 18 tanks, each connected to three faecal settling tanks. All aquaria were stocked with 20 fish (82 g per fish). After 52 experimental days, dietary viscosity negatively affected both feed digestibility and performance of striped catfish; as a result, the amount of organic matter in the culture system through faeces had increased significantly. The coarse diets significantly increased the digestibility of dry matter and carbohydrate but worsened feed conversion ratio. Increasing dietary viscosity tended to increase the viscosity and moisture content of the faeces, but significantly accelerated the faecal disintegration through the reduction of both faecal recovery and the amount of recovered faeces. [ABSTRACT FROM AUTHOR]

This paper investigates low temperature ohmic contact formation of Au/Sb to n-type Si substrates through AuSb/NiCr/Au metal stacks. Liquid epitaxy growth is utilized to incorporate Sb dopants into Si substrate in AuSi melt. The best specific contact resistivity achieved is 0.003Ω·cm² at 425 °C. Scanning electron microscopy (SEM) reveals inverted pyramidal crater regions at the metal/semiconductor interface, indicating that AuSi alloying efficiently occurs at such sites. Secondary ion mass spectroscopy (SIMS) shows that Sb atoms are successfully incorporated into Si as doping impurities during the anneal process, and the Sb doping concentration at the contact interface is found to be higher than the solid solubility limit in a Si crystal. This ohmic contacts formation method is suitable for semiconductor fabrication processes with limited thermal budget, such as post CMOS integration of MEMS. [ABSTRACT FROM AUTHOR]

Gravity gradient measurement makes use of the difference between the outputs of pairs of linear accelerometers, which results in cancelling out the common mode accelerations caused by mounting platform and external environment. One of the key technologies is to match the acceleration-to-voltage or acceleration-to-current transfer functions of the pairs of the accelerometers to an extremely high degree of accuracy. The differential signals then make the gravity gradients observable. By using two pairs of the quartz-flexure accelerometers with a capacitive sensing and electrostatic closed-loop control, the electrostatic control bias voltages were trimming remotely and automatically in real time. Each pair of accelerometers was matched individually and then all four accelerometers were finally re-balanced. The experimental results show that the consistency of five digits is achieved at a noise level of ~5 x 10-8 g/√Hz (1 g ≈ 9.8 m/s²) and the scale factors ranging from 0.25 to 0.32 V/mg. Further improvement to the achieved level of matching is limited by the intrinsic noise of the accelerometers used. [ABSTRACT FROM AUTHOR]

Treatment of cultured human hepatoma HepG2 cells with the protein kinase C (PKC) activator, 12-O-tetradecanoylphorbol-13-acetate (TPA), results in an increase in tyrosine phosphorylation of several proteins, including the focal adhesion kinase (FAK) and paxillin using anti-phosphotyrosine Western blotting and immunoprecipitation. However, when cells are in suspension or in the presence of cytochalasin D which disrupts the intracellular network of actin microfilaments, TPA loses its ability to stimulate tyrosine phosphorylation of FAK and paxillin but it still activates mitogen-activated protein kinase (MAPK) and induces PKC translocation from cytosol to the membrane in HepG2 cells. On the other hand, PD98059, a specific inhibitor of mitogen-activated protein kinase kinase, blocks TPA-induced MAPK activation but has no effect on TPA-induced tyrosine phosphorylation. Our findings suggest that TPA-induced tyrosine phosphorylation of FAK and paxillin in human hepatoma cells is PKC dependent and requires the integrity of the cell cytoskeleton but is uncoupled to the signal transduction pathway of PKC leading to the translocation of PKC and MAPK activation., (Copyright 2001 National Science Council, ROC and S. Karger AG, Basel)