Steady direct current (dc) electric fields exist in many biological systems over many hours. At these times cells are dividing, differentiating, moving to final locations and extending motile processes. Each of these events may be influenced by physiological electric fields in tissue culture and when electric fields are disrupted in vivo, major developmental abnormalities arise. The likelihood of physiological electric fields playing a role in cell behaviours and some potential mechanisms are outlined.

The energy hole is a severe problem for underwater acoustic distributed networks in that it affects the normal operations of the network and shortens the network’s life span. To deal with this problem, a loop-free routing control technique is proposed in this paper. The classical shortest-path routing control method is used to generate multiple disjointed routing tables. The residual energy of the nodes and the changing information of the uplink/downlink matrix are added to the data frames for distribution. The source (...) node specifies the routing path to transmit the data frames based on the changing information, and the relay nodes route the data frames strictly according to the routing path designated by the source node. Besides, the energy consumption of the relay node is saved by replying to the pseudo-ACK frame. Simulation experiments are implemented in four typical scenarios, and the results reflect that the proposed technique could extend the network’s life span by approximately 10% when compared to other mature techniques. Besides, it has no other negative effects on the normal operations of the network. (shrink)

劉沅(1767～1855)，祖籍湖北麻城劉家溝，先祖於明末遷蜀。劉沅出生於雙流雲棲裡，嘉慶十二年(1807) 遷居成都淳化街。因劉沅在雙流和成都的書塾中均有一株古槐，故世稱劉沅為“槐軒先生”，其學為“槐軒之學”。劉沅是學問大家，現存著述逾200卷。本書作者2010年開始以槐軒學派的學術思想作為研究物件，以劉沅 所關懷之社會歷史問題為軸心展開探討，闡明其逾出當時知識界義理與考據之爭的真正深意，在於重建社會整體性的價值信念系統。.