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11.
We consider applying a functional logistic discriminant procedure to the analysis of handwritten character data. Time-course trajectories corresponding to the X and Y coordinate values of handwritten characters written in the air with one finger are converted into a functional data set via regularized basis expansion. We then apply functional logistic modeling to classify the functions into several classes. In order to select the values of adjusted parameters involved in the functional logistic model, we derive a model selection criterion for evaluating models estimated by the method of regularization. Results indicate the effectiveness of our modeling strategy in terms of prediction accuracy.  相似文献   
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Gas hydrates are a significant energy resource and are usually detected by bottom simulating reflection and submarine geochemical anomalies. Authigenic minerals are related to gas hydrates, with carbonates, sulfates and sulfides being important tracing minerals. Authigenic tubular pyrites were collected from offshore southwest Taiwan in the South China Sea, and were investigated by scanning electron microscopy(SEM) and high-resolution transmission electron microscopy (HRTEM). Authigenic tubular pyrite was composed of framboidal pyrite, within which nanosized graphitic carbon of low crystallinity was discovered. The graphitic carbon coexisted with pyrite and had a texture similar to carbon nanotubes and nanocones, indicating that they likely precipitated from carbon supersaturated C-H-O fluid. Pyrite may act as a catalyst for the conversion of CH 4 to C. The discovery of nanosized graphitic carbon in pyrite indicated it was deposited in sediments that were supersaturated with methane fluid. Thus, nanosized graphitic carbon may be another tracing species for submarine gas hydrates. The discovery of nanosized graphitic carbon deposited in a low temperature environment will enlighten our understanding of the laboratory synthesis and industrial production of graphitic carbon.  相似文献   
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S Konishi  A Tsunoo  M Otsuka 《Nature》1979,282(5738):515-516
Recent biochemical and immunohistochemical studies have shown that the opioid peptides, enkephalins, occur in nerve terminals and cell bodies in mammalian sympathetic ganglia1-3. Opiates and enkephalins are thought to inhibit synaptic transmission in the peripheral nervous tissues as well as in the central nervous system4-12. The mechanisms of the opiate actions, however, are not entirely clear; both pre- and postsynaptic sites of action have been proposed7-9,11,12. As acetylcholine is known to be the major neurotransmitter in the autonomic ganglia and as the mechanism of synaptic transmission is well clarified13, analysis of the peptide action could be more easily but equally usefully carried out in the peripheral synapses than in central synapses. We now report that enkephalins presynaptically inhibit cholinergic transmission in sympathetic ganglia.  相似文献   
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A silicon transporter in rice   总被引:19,自引:0,他引:19  
Ma JF  Tamai K  Yamaji N  Mitani N  Konishi S  Katsuhara M  Ishiguro M  Murata Y  Yano M 《Nature》2006,440(7084):688-691
Silicon is beneficial to plant growth and helps plants to overcome abiotic and biotic stresses by preventing lodging (falling over) and increasing resistance to pests and diseases, as well as other stresses. Silicon is essential for high and sustainable production of rice, but the molecular mechanism responsible for the uptake of silicon is unknown. Here we describe the Low silicon rice 1 (Lsi1) gene, which controls silicon accumulation in rice, a typical silicon-accumulating plant. This gene belongs to the aquaporin family and is constitutively expressed in the roots. Lsi1 is localized on the plasma membrane of the distal side of both exodermis and endodermis cells, where casparian strips are located. Suppression of Lsi1 expression resulted in reduced silicon uptake. Furthermore, expression of Lsi1 in Xenopus oocytes showed transport activity for silicon only. The identification of a silicon transporter provides both an insight into the silicon uptake system in plants, and a new strategy for producing crops with high resistance to multiple stresses by genetic modification of the root's silicon uptake capacity.  相似文献   
15.
Generalized Partial Computation (GPC) is a program transformation method utilizing partial information about input data, properties of auxiliary functions and the logical structure of a source program. GPC uses both an inference engine such as a theorem prover and a classical partial evaluator to optimize programs. Therefore, GPC is more powerful than classical partial evaluators but harder to implement and control. We have implemented an experimental GPC system called WSDFU (Waseda Simplify-Distribute-Fold-Unfold). This paper discusses the power of the program transformation system, its theorem prover and future works.  相似文献   
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S Konishi  M Otsuka 《Nature》1974,252(5485):734-735
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Zusammenfassung Decalysin, Polyarginin, Polylysin, Polyornithin, Kalbsthymushistone und Polypeptidhormone stimulieren in niedriger Konzentration die DNA-abhängige RNS-Polymerase-Aktivität vonEscherichia coli, während sie in hoher Konzentration die Enzymaktivität hemmen.  相似文献   
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