Due to interference of vegetation by experiment in wind tunnel and observation in field,the boundary layer is divided into 2 sublayers approximately at the vegetation height.As for the vertical wind gradient,it change...Due to interference of vegetation by experiment in wind tunnel and observation in field,the boundary layer is divided into 2 sublayers approximately at the vegetation height.As for the vertical wind gradient,it changes disorderly in rough sublayer of the lower and changes regularly in inertial sublayer of the upper varying with vegetation characteristics.Erosion rate increases exponentially with vegetation coverage reduction.The establishment of shrub shelterbelt along Tarim Desert Highway made obvious effects not only on wind preventing and sand binding,but also on microclimate.Compared with mobile dune,air temperature is higher in summer and lower in autumn,while relative moisture is higher,and evaporation and soil temperature lower in the shrub shelterbelt.展开更多
A concept of tissue adaptation to hypoxia(i.e. hypoxic preconditioning) was developed and its corresponding animal models were reproduced in 1966s. The methods of model reproduction in rat,rabbit,and mouse in particul...A concept of tissue adaptation to hypoxia(i.e. hypoxic preconditioning) was developed and its corresponding animal models were reproduced in 1966s. The methods of model reproduction in rat,rabbit,and mouse in particular and the main results are brifly introduced in this review. The tolerance to hypoxia of preconditioned animals is significantly increased. Regular changes in animals’ behavior,neurophysiology,respiratory and circulatory physiology,neuromorphology in vivo and function of brain and spinal cord in vitro are briefly demonstrated.The protective effects in vivo and in vitro of homogenate extract taken from the brain of preconditioned animals,neurochemcals and molecular neurobiological alterations are briefly presented. The essence and significance of tissue adaption to hypoxia/hypoxic preconditioning are discussed in the review in terms of evolution and practical implication.展开更多
文摘Due to interference of vegetation by experiment in wind tunnel and observation in field,the boundary layer is divided into 2 sublayers approximately at the vegetation height.As for the vertical wind gradient,it changes disorderly in rough sublayer of the lower and changes regularly in inertial sublayer of the upper varying with vegetation characteristics.Erosion rate increases exponentially with vegetation coverage reduction.The establishment of shrub shelterbelt along Tarim Desert Highway made obvious effects not only on wind preventing and sand binding,but also on microclimate.Compared with mobile dune,air temperature is higher in summer and lower in autumn,while relative moisture is higher,and evaporation and soil temperature lower in the shrub shelterbelt.
文摘A concept of tissue adaptation to hypoxia(i.e. hypoxic preconditioning) was developed and its corresponding animal models were reproduced in 1966s. The methods of model reproduction in rat,rabbit,and mouse in particular and the main results are brifly introduced in this review. The tolerance to hypoxia of preconditioned animals is significantly increased. Regular changes in animals’ behavior,neurophysiology,respiratory and circulatory physiology,neuromorphology in vivo and function of brain and spinal cord in vitro are briefly demonstrated.The protective effects in vivo and in vitro of homogenate extract taken from the brain of preconditioned animals,neurochemcals and molecular neurobiological alterations are briefly presented. The essence and significance of tissue adaption to hypoxia/hypoxic preconditioning are discussed in the review in terms of evolution and practical implication.