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The harsh conditions of the gastrointestinal tract limit the potential health benefits of oral probiotics. It is promising that oral bioavailability is improved by strengthening the self-protection of probiotics. Here, we report the encapsulation of a probiotic strain by endogenous production of hyaluronan to enhance the effects of oral administration of the strain. The traditional probiotic

Internal tides generated by the interaction of the barotropic tide with bottom topography are studied by using an analytical solution. Tide-topography resonance takes place when the wavenumber of the truncated sinusoidal topography is equal to that of one baroclinic mode. The minimum amplitude of the resonant mode increases from the center of the domain to both sides of the topography; while the maximum keeps the same. Amplitudes of the internal tides and mode conversion rate are analyzed as a function of the length and wavenumber of the topography. For non-resonant modes, the amplitudes are weak and vary periodically with the extending of the topography, and are exactly zero when the length of topography is integral times of the mode-1 wavelength. For resonant modes, the amplitudes increase with the length of the topography. For each internal tide mode, there is a response zone, where the amplitude for one mode is obviously larger than other baroclinic modes. The response zones for high modes are wider than those for low modes. Mode conversion rate is obviously high when the wavenumber of the topography is equal to that of the baroclinic modes; otherwise it is almost zero. Furthermore, mode conversion rate for small topography wavenumber is more than that for large topography wavenumber with the same number of the sinusoidal topography, and is less with the same topography length.

Here the process of internal tide generation over idealized (sinusoidal) topography was investigated using numerical techniques, in which the barotropic-to-baroclinic energy conversion was discussed. The result shows that when the wavenumber of the sinusoidal topography, ktopo, is equal to the horizontal wavenumber of the m-th baroclinic mode km, the conversion from the barotropic tide to the m-th baroclinic mode is enhanced with the increase of topography length; When the wavenumber of the sinusoidal topography is not equal to horizontal wavenumbers of any baroclinic modes, ktopo≠km(m=1,2,...), conversion from the barotropic energy to baroclinic modes is decreased with the increase of topography length. Furthermore, it shows that in resonance case, the phase of the perturbation pressure gradually agrees with the phase of the truncated sinusoidal topography, and the conversion rate is always positive over the topography, thus the baroclinic mode which matches with the wavenumber of the sinusoidal topography persists in absorbing energy from the barotropic tide, and the conversion rate is increased.

To evaluate the biological characteristics of Campylobacter jejuni (CJ) cultured on different culture media and their expression abundance of outer membrane proteins (OMPs).CJ was cultured on the improved Bull's medium yolk agar, improved Bull's blood agar or improved Bull's agar for 48 h. The biological characteristics of the bacteria, including the colony feature, morphology, motility, biochemistry, and results of indirect fluorescence test were observed and compared. OMP of the cultured CJ was extracted using 0.2 mol/L and glycine-hydrochloride buffered solution (pH 2.2) and identified by SDS-PAGE to compare the expression abundance of the OMPs with molecular weight of 28-31 kD.CJ exhibited typical biological characteristics with larger cell body and more rapid growth on improved Bull's medium yolk agar than those on improved Bull's blood agar and improved Bull's agar. The bacteria grown on improved Bull's medium yolk agar showed also greater expression abundance of the OMPs with molecule mass between 28 kD and 31 kD.Improved Bull's medium yolk agar allows rapid growth of CJ with typical biological characteristics and enhanced expression of the OMPs with molecular weight of 28 -31 kD, and can be widely used in CJ subunit vaccine development, CJ epidemiological survey, CJ food safety examination, and CJ quarantine.