Mobile sink is the challenging task for wireless sensor networks(WSNs).In this paper we propose to design an efficient routing protocol for single mobile sink and multiple mobile sink for data gathering in WSN.In this...Mobile sink is the challenging task for wireless sensor networks(WSNs).In this paper we propose to design an efficient routing protocol for single mobile sink and multiple mobile sink for data gathering in WSN.In this process,a biased random walk method is used to determine the next position of the sink.Then,a rendezvous point selection with splitting tree technique is used to find the optimal data transmission path.If the sink moves within the range of the rendezvous point,it receives the gathered data and if moved out,it selects a relay node from its neighbours to relay packets from rendezvous point to the sink.Proposed algorithm reduces the signal overhead and improves the triangular routing problem.Here the sink acts as a vehicle and collect the data from the sensor.The results show that the proposed model effectively supports sink mobility with low overhead and delay when compared with Intelligent Agent-based Routing protocol(IAR) and also increases the reliability and delivery ratio when the number of sources increases.展开更多
Interleukin-2 （IL）-2 signaling plays a pivotal role in the activation of immune responses, and drugs that block this pathway have been shown to be effective for the immunosuppression in patients with organ transplan...Interleukin-2 （IL）-2 signaling plays a pivotal role in the activation of immune responses, and drugs that block this pathway have been shown to be effective for the immunosuppression in patients with organ transplantation to alleviate/eliminate allograft rejection. The first humanized monoclonal antibody （mAb） daclizumab falls into this category and shows high specificity and affinity against a key component of the IL-2 receptor complex, namely IL-2Ra. To reveal the molecular mechanism of the inhibition of the IL-2 signaling pathway by dacllzumab, we determined the crystal structures of the daclizumab Fab in free form and in complex with the IL-2Ra ectodomain at 2.6 and 2.8 A resolution, respectively. The daclizumab Fab adopts a similar conformation in the presence or absence of the IL- 2Ra ectodomain. The antigen-binding site of daclizumab is mainly composed of live complementarity determining regions （CDRs） that form a large positively charged surface depression and two flanking patches that are generally hydrophobic. The conformational epitope consists of several discontinuous segments of the IL-2Ru ectodomain, a large portion of which overlaps with the regions that interact with IL-2, suggesting that the binding of daclizumab to IL-2Ra would prevent the IL-2 binding to IL-2Ra and the subsequent formation of the IL-2fIL-2Ra[~/c complex, and therefore block the IL-2 signaling pathway. These results also have implications for the design and development of improved mAb drugs targeting IL-2Ra.展开更多
Lepidoptera evolved tympanic ears in response to echolocating bats. Comparative studies have shown that moth ears evolved many times independently from chordotonal organs. With only 1 to 4 receptor cells, they are one...Lepidoptera evolved tympanic ears in response to echolocating bats. Comparative studies have shown that moth ears evolved many times independently from chordotonal organs. With only 1 to 4 receptor cells, they are one of the simplest hearing organs. The small number of receptors does not imply simplicity, neither in behavior nor in the neural circuit. Behaviorally, the response to ultrasound is far from being a simple reflex. Moths＇ escape behavior is modulated by a variety of cues, especially pheromones, which can alter the auditory response. Neurally the receptor cell（s） diverges onto many interneurons, enabling pa- rallel processing and feature extraction. Ascending interneurons and sound-sensitive brain neurons innervate a neuropil in the ventrolateral protocerebrum. Further, recent electrophysiological data provides the first glimpses into how the acoustic response is modulated as well as how ultrasound influences the other senses. So far, the auditory pathway has been studied in noctuids. The findings agree well with common computational principles found in other insects. However, moth ears also show unique mechanical and neural adaptation. Here, we first describe the variety of moths＇ auditory behavior, especially the co-option of ul- trasonic signals for intraspecific communication. Second, we describe the current knowledge of the neural pathway gained from noctuid moths. Finally, we argue that Galleriinae which show negative and positive phonotaxis, are an interesting model species for future electrophysiological studies of the auditory pathway and multimodal sensory integration, and so are ideally suited for the study of the evolution of behavioral mechanisms given a few receptors.展开更多
文摘Mobile sink is the challenging task for wireless sensor networks(WSNs).In this paper we propose to design an efficient routing protocol for single mobile sink and multiple mobile sink for data gathering in WSN.In this process,a biased random walk method is used to determine the next position of the sink.Then,a rendezvous point selection with splitting tree technique is used to find the optimal data transmission path.If the sink moves within the range of the rendezvous point,it receives the gathered data and if moved out,it selects a relay node from its neighbours to relay packets from rendezvous point to the sink.Proposed algorithm reduces the signal overhead and improves the triangular routing problem.Here the sink acts as a vehicle and collect the data from the sensor.The results show that the proposed model effectively supports sink mobility with low overhead and delay when compared with Intelligent Agent-based Routing protocol(IAR) and also increases the reliability and delivery ratio when the number of sources increases.
基金Acknowledgments We are grateful to the staff members at Shanghai Synchrotron Radiation Facility for support in diffraction data collection and other members of our group for helpful discussion. This work was supported by grants from the Ministry of Science and Technology of China （2010CB833601, 2006AA02A313, and 2009ZX09503- 009）, the National Natural Science Foundation of China （30730028 and 90713046）, and the Chinese Academy of Sciences （KSCX2-YW-R- 107 and SIBS2008002）.
文摘Interleukin-2 （IL）-2 signaling plays a pivotal role in the activation of immune responses, and drugs that block this pathway have been shown to be effective for the immunosuppression in patients with organ transplantation to alleviate/eliminate allograft rejection. The first humanized monoclonal antibody （mAb） daclizumab falls into this category and shows high specificity and affinity against a key component of the IL-2 receptor complex, namely IL-2Ra. To reveal the molecular mechanism of the inhibition of the IL-2 signaling pathway by dacllzumab, we determined the crystal structures of the daclizumab Fab in free form and in complex with the IL-2Ra ectodomain at 2.6 and 2.8 A resolution, respectively. The daclizumab Fab adopts a similar conformation in the presence or absence of the IL- 2Ra ectodomain. The antigen-binding site of daclizumab is mainly composed of live complementarity determining regions （CDRs） that form a large positively charged surface depression and two flanking patches that are generally hydrophobic. The conformational epitope consists of several discontinuous segments of the IL-2Ru ectodomain, a large portion of which overlaps with the regions that interact with IL-2, suggesting that the binding of daclizumab to IL-2Ra would prevent the IL-2 binding to IL-2Ra and the subsequent formation of the IL-2fIL-2Ra[~/c complex, and therefore block the IL-2 signaling pathway. These results also have implications for the design and development of improved mAb drugs targeting IL-2Ra.
文摘Lepidoptera evolved tympanic ears in response to echolocating bats. Comparative studies have shown that moth ears evolved many times independently from chordotonal organs. With only 1 to 4 receptor cells, they are one of the simplest hearing organs. The small number of receptors does not imply simplicity, neither in behavior nor in the neural circuit. Behaviorally, the response to ultrasound is far from being a simple reflex. Moths＇ escape behavior is modulated by a variety of cues, especially pheromones, which can alter the auditory response. Neurally the receptor cell（s） diverges onto many interneurons, enabling pa- rallel processing and feature extraction. Ascending interneurons and sound-sensitive brain neurons innervate a neuropil in the ventrolateral protocerebrum. Further, recent electrophysiological data provides the first glimpses into how the acoustic response is modulated as well as how ultrasound influences the other senses. So far, the auditory pathway has been studied in noctuids. The findings agree well with common computational principles found in other insects. However, moth ears also show unique mechanical and neural adaptation. Here, we first describe the variety of moths＇ auditory behavior, especially the co-option of ul- trasonic signals for intraspecific communication. Second, we describe the current knowledge of the neural pathway gained from noctuid moths. Finally, we argue that Galleriinae which show negative and positive phonotaxis, are an interesting model species for future electrophysiological studies of the auditory pathway and multimodal sensory integration, and so are ideally suited for the study of the evolution of behavioral mechanisms given a few receptors.
