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Qinghai Lake is a major migratory-bird breeding site that has experienced several highly pathogenic avian influenza virus (AIV) epizootics. Plateau pikas ( Ochotona curzoniae) have previously been implicated in the ecology of avian influenza virus in this region. We first isolated an H9N2 AIV (A/Pika/Menyuan/01/2008) from plateau pikas between November 2008 and October 2009. Sequence analysis showed that the A/Pika/Menyuan/01/2008 AIV was closely related to the H9N2 AIV strain (A/Turkey/Wisconsin/ 1/1966). Our findings suggested that plateau pikas may contribute to AIV epidemiology in the Qinghai Lake region. [ABSTRACT FROM AUTHOR]

For the past decades, networked control systems (NCSs), as an interdisciplinary subject, have been one of the main research highlights and many fruitful results from different aspects have been achieved. With these growing research trends, it is significant to consolidate the latest knowledge and information to keep up with the research needs. In this paper, the results of different aspects of NCSs, such as quantization, estimation, fault detection and networked predictive control, are summarized. In addition, with the development of cloud technique, cloud control systems are proposed for the further development of NCSs. [ABSTRACT FROM AUTHOR]

Based on the vehicle-track coupling dynamics theory, a new spatial dynamic numerical model of vehicle-track-subgrade coupling system was established considering the interaction among different structural layers in the subgrade system. The dynamic responses of the coupled system were analyzed when the speed of train was 350 km/h and the transition was filled with graded broken stones mixed with 5% cement. The results indicate that the setting form of bridge-approach embankment section has little effect on the dynamic responses, thus designers can choose it on account of the practical circumstances. Because the location about 5 m from the bridge abutment has the greatest deformation, the stiffness within 0-5 m zone behind the abutment should be specially designed. The results of the study from vehicle-track dynamics show that the maximum allowable track deflection angle should be 0.09% and the coefficient of subgrade reaction ( K) is greater than 190 MPa within the 0-5 m zone behind the abutment and greater than 150 MPa in other zones. [ABSTRACT FROM AUTHOR]

Glycinebetaine is an important quaternary ammonium compound generated in response to salt and other osmotic stresses in many organisms. Its synthesis requires the catalysis of betaine aldehyde dehydrogenase encoded by a Betaine Aldehyde Dehydrogenase ( BADH) gene that converts betaine aldehyde into glycinebetaine in some halotolerant plants. In this study, a BADH gene was over expressed in transgenic alfalfa ( Medicago sativa L) plants using Agrobacterium-mediated transformation. Transgenic alfalfa plants grown under 9‰ NaCl grew well; while non-transgenic control plants turned yellowish in color, wilted, and eventually died. Polymerase chain reaction (PCR) and Northern blot hybridization analyses demonstrated that the BADH gene was transferred into the T2 generation and segregated in a Mendelian fashion. Transgenic alfalfa plants expressing BADH showed significantly higher BADH enzyme activity and betaine contents when grown under 6‰ NaCl. Moreover, proline content in T2 lines were higher while electrolyte leakage and malonaldehyde content were lower in T2 lines compared with non-transgenic plants. These findings indicated that transgenic plants expressing BADH transgene exhibited higher salt tolerance than non-transgenic plants. [ABSTRACT FROM AUTHOR]

Puerarin, a major isoflavonoid compound from the Chinese herb, Ge-gen ( Pueraria lobata), has effective treatment on myocardial and cerebral ischemia, glaucoma and sudden deafness in clinical setting in China. Our present work showed that puerarin (50, 150, 450 μM) concentration-dependently inhibited phenylephrine or KCl-induced contraction only in endothelium-intact rat aortic rings. In Ca2+-free solution, the antivasoconstriction of puerarin on phenylephrine was totally deprived. NG-nitro- l-arginine methyl ester, 1 H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, indomethacin and the three K+ channel blockers, glibenclamide, tetraethylammonium and Ba2+ displayed significant inhibitory effects on the antivasoconstriction of puerarin. 8-bromo-cGMP significantly strengthened the action of puerarin. Puerarin (10–160 μM) concentration-dependently induced the NO production in the rat aortic cells. These findings suggested that the antivasoconstriction elicited by puerarin is endothelium-dependent. NO/NO–cGMP pathway, PGI2 and the opening of K+ channels sensitive to glibenclamide, tetraethylammonium, and Ba2+, which might be triggered by the extracellular Ca2+ influx in the endothelium, appear to contribute to the antivasoconstriction of puerarin. [ABSTRACT FROM AUTHOR]