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Rotary lime kiln is an important pulp production facility of paper mills and cement factories. To achieve fully-automated lime kiln production, this paper firstly carries out a thorough review of the production processes of lime kiln, revealing that the shell temperature of lime kiln and furnace oil consumption are two key parameters to the working efficiency and product quality of the kiln. Next, an expert system was designed based on artificial neural network to optimize the parameters in kiln application. The functions and operations of the intelligent controllers in the system were also detailed. After that, the designed system was adopted to predict the shell temperature and furnace oil consumption using moisture in lime mud. The comparison between the predicted results and the real-time data of a plant shows that our system can predict the two key parameters accurately, enabling the operator to make sound decisions on many production indices. The research findings lay the basis for low-cost and high-quality lime kiln operations.

White spot syndrome caused by white spot syndrome virus (WSSV) is one of the most threatening diseases of shrimp culture industry. Previous studies have successfully demonstrated the use of DNA- and RNA-based vaccines to protect WSSV infection in shrimp. In the present study, we have explored the protective efficacy of antisense constructs directed against WSSV proteins, VP24, and VP28, thymidylate synthase (TS), and ribonucleotide reductase-2 (RR2) under the control of endogenous shrimp histone-3 (H3) or penaedin (Pn) promoter. Several antisense constructs were generated by inserting VP24 (pH3-VP24, pPn-VP24), VP28 (pH3-VP28, pPn-VP28), TS (pH3-TS, pPn-TS), and RR2 (pH3-RR2) in antisense orientation. These constructs were tested for their protective potential in WSSV infected cell cultures, and their effect on reduction of the viral load was assessed. A robust reduction in WSSV copy number was observed upon transfection of antisense constructs in hemocyte cultures derived from Penaeus monodon and Scylla serrata. When tested in vivo, antisense constructs offered a strong protection in WSSV challenged P. monodon. Constructs expressing antisense VP24 and VP28 provided the best protection (up to 90 % survivability) with a corresponding decrease in the viral load. Our work demonstrates that shrimp treated with antisense constructs present an efficient control strategy for combating WSSV infection in shrimp aquaculture.

This work describes experiments in which a stably stratified salt solution is subjected to steady lateral temperature gradients. The criteria for the onset of layered convection are observed to agree with previously published stability analysis. Convective layers formed in this way are found to be statically unstable; they always merge two into one to form a new system. This process continues until the density jump at the solute interface between layers is larger than the density deficit produced by the side wall heating/cooling. The eventual stable system develops into well-mixed convective layers separated by sharp solute interfaces. The conditions for any subsequent layer intermixing and its effect on the lateral heat transfer across the slot, are also described.

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