压应力对铁电陶瓷非线性力电耦合性能的影响

回顾了关于轴向压应力与侧向压应力对铁电陶瓷非线性力电耦合性能影响的实验结果,提出了一个新的电畴翻转模型,将180°电畴翻转分成两次连续的90°翻转.在压应力方向与极化方向平行的情况下,陶瓷中的电畴翻转近似为轴对称的,可以用一个解析的模型来模拟.而在压应力方向与极化方向垂直的情况下,电畴翻转是三维的,因而无法简化.两种情况下模型的模拟结果均与实验结果符合较好,从而说明了该模型的有效性.回顾了关于轴向压应力与侧向压应力对铁电陶瓷非线性力电耦合性能影响的实验结果,提出了一个新的电畴翻转模型,将180°电畴翻转分成两次连续的90°翻转.在压应力方向与极化方向平行的情况下,陶瓷中的电畴翻转近似为轴对称的,可以用一个解析的模型来模拟.而在压应力方向与极化方向垂直的情况下,电畴翻转是三维的,因而无法简化.两种情况下模型的模拟结果均与实验结果符合较好,从而说明了该模型的有效性.     

等离子体波导中电磁波传输理论

对圆柱波导中的介质管内填充等离子体且外加有限轴向磁场时，电磁波的传播特性进行了严格的理论分析，得到了电磁场分量，特征值，色散方程和复功率流的严格表达式，并进行了详细讨论。     

A membrane-access mechanism of ion channel inhibition by voltage sensor toxins from spider venom

Venomous animals produce small protein toxins that inhibit ion channels with high affinity. In several well-studied cases the inhibitory proteins are water-soluble and bind at a channel's aqueous-exposed extracellular surface. Here we show that a voltage-sensor toxin (VSTX1) from the Chilean Rose Tarantula (Grammostola spatulata) reaches its target by partitioning into the lipid membrane. Lipid membrane partitioning serves two purposes: to localize the toxin in the membrane where the voltage sensor resides and to exploit the free energy of partitioning to achieve apparent high-affinity inhibition. VSTX1, small hydrophobic poisons and anaesthetic molecules reveal a common theme of voltage sensor inhibition through lipid membrane access. The apparent requirement for such access is consistent with the recent proposal that the sensor in voltage-dependent K+ channels is located at the membrane-protein interface.     

A systematic RNAi screen identifies a critical role for mitochondria in C. elegans longevity

We report a systematic RNA interference (RNAi) screen of 5,690 Caenorhabditis elegans genes for gene inactivations that increase lifespan. We found that genes important for mitochondrial function stand out as a principal group of genes affecting C. elegans lifespan. A classical genetic screen identified a mutation in the mitochondrial leucyl-tRNA synthetase gene (lrs-2) that impaired mitochondrial function and was associated with longer-lifespan. The long-lived worms with impaired mitochondria had lower ATP content and oxygen consumption, but differential responses to free-radical and other stresses. These data suggest that the longer lifespan of C. elegans with compromised mitochrondria cannot simply be assigned to lower free radical production and suggest a more complex coupling of metabolism and longevity.     

C. elegans ORFeome version 1.1: experimental verification of the genome annotation and resource for proteome-scale protein expression

To verify the genome annotation and to create a resource to functionally characterize the proteome, we attempted to Gateway-clone all predicted protein-encoding open reading frames (ORFs), or the 'ORFeome,' of Caenorhabditis elegans. We successfully cloned approximately 12,000 ORFs (ORFeome 1.1), of which roughly 4,000 correspond to genes that are untouched by any cDNA or expressed-sequence tag (EST). More than 50% of predicted genes needed corrections in their intron-exon structures. Notably, approximately 11,000 C. elegans proteins can now be expressed under many conditions and characterized using various high-throughput strategies, including large-scale interactome mapping. We suggest that similar ORFeome projects will be valuable for other organisms, including humans.     

Cellular and molecular action of the putative GABA-mimetic,gabapentin

Gabapentin was originally designed as an anti-convulsant gamma-aminobutyric acid (GABA) mimetic capable of crossing the blood-brain barrier. In the present review we show that although gabapentin is not a GABA mimetic, it has great utility as an add-on therapy for epilepsy and as a first-line treatment for neuropathic pain. We summarise the studies that have been performed which demonstrate that gabapentin appears to interact with a novel binding site expressed at high density within the central nervous system (CNS), namely the alpha2delta voltage-dependent calcium channel subunit. The review continues by examining the effects of gabapentin on calcium channel function and neurotransmitter release before, in the latter part of the review, summarising the more recently discovered actions of gabapentin in relation to intracellular signalling.