Optimal design of blade in pump as turbine based on multidisciplinary feasible method.

In order to make the pump as turbine (PAT) run efficiently and safely, a multidisciplinary optimization design method for PAT blade, which gives consideration to both the hydraulic and intensity performances, is proposed based on multidisciplinary feasibility (MDF) optimization strategy. This method includes blade parametric design, Latin Hypercube Sampling (LHS) experimental design, CFD technology, FEA technology, GA-BP neural network and NSGA-II algorithm. Specifically, a parameterized PAT blade with cubic non-uniform B-spline curve is adopted, and the control point of blade geometry is taken as the design variable.

High prevalence of bovine viral diarrhea virus 1 in Chinese swine herds.

Nested RT-PCR was used to investigate bovine viral diarrhea virus in 511 specimens collected from Chinese pigs exhibiting clinical symptoms between 2007 and 2010. Of these, 137 samples were BVDV-positive and the BVDV prevalence rate was 23.1% (9/39) in 2007, 27.

Detection of a novel porcine parvovirus, PPV4, in Chinese swine herds.

To determine whether the novel porcine parvovirus type 4 (PPV4) recently reported in America is prevalent in China, a set of specific primers was designed and used for molecular survey of PPV4 among the clinical samples collected from various provinces of China between 2006 and 2010. The results showed that PPV4 is present in Chinese swine herds at a rate of 2.09% (12/573) among the clinical samples examined and 0.