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101.
We evaluate the Fisher information of a population of model neurons that receive dynamical input and interact via spikes. With spatially independent threshold noise, the spike-based Fisher information that summarizes the information carried by individual spike timings has a particularly simple analytical form. We calculate the loss of information caused by abandoning spike timing and study the effect of synaptic connections on the Fisher information. For a simple spatiotemporal input, we derive the optimal recurrent connectivity that has a local excitation and global inhibition structure. The optimal synaptic connections depend on the spatial or temporal feature of the input that the system is designed to code. 相似文献
102.
Hirai H Komatsu K Honda M Kawamura T Yamamoto Y Yagi T 《The Journal of chemical physics》2010,133(12):124511
High pressure and low temperature experiments with CO(2) hydrate were performed using diamond anvil cells and a helium-refrigeration cryostat in the pressure and temperature range of 0.2-3.0 GPa and 280-80 K, respectively. In situ x-ray diffractometry revealed that the phase boundary between CO(2) hydrate and water+CO(2) extended below the 280 K reported previously, toward a higher pressure and low temperature region. The results also showed the existence of a new high pressure phase above approximately 0.6 GPa and below 1.0 GPa at which the hydrate decomposed to dry ice and ice VI. In addition, in the lower temperature region of structure I, a small and abrupt lattice expansion was observed at approximately 210 K with decreasing temperature under fixed pressures. The expansion was accompanied by a release of water content from the sI structure as ice Ih, which indicates an increased cage occupancy. A similar lattice expansion was also described in another clathrate, SiO(2) clathrate, under high pressure. Such expansion with increasing cage occupancy might be a common manner to stabilize the clathrate structures under high pressure and low temperature. 相似文献
103.
Onoda A Ueya Y Sakamoto T Uematsu T Hayashi T 《Chemical communications (Cambridge, England)》2010,46(48):9107-9109
Interaction of apohemoprotein with a covalently immobilized heme moiety onto a gold nanoparticle surface resulted in supramolecular hemoprotein-gold nanoparticle conjugates. The addition of an apohemoprotein dimer further led to a densely-packed hemoprotein-gold nanoparticle assembly, which was visualized by TEM and AFM measurements. 相似文献
104.
Yamada T Noto M Shirasaka K Kato HS Kawai M 《The journal of physical chemistry. B》2006,110(13):6740-6749
Ultraviolet photoassisted adsorption of terminally double-bonded molecules, allylamine (CH2=CH-CH2-NH2) and 1-butene (CH2=CH-CH2-CH3), on hydrogen-terminated silicon (111) surface was attempted to obtain adsorbates covalently terminating the surface Si atoms. The adsorption process was monitored by high-resolution electron energy loss spectroscopy, multiple internal infrared reflection-absorption spectroscopy, and Auger electron spectroscopy. Allylamine adsorbates emerged upon delivery of allylamine gas under ultraviolet irradiation. The N-H bonds in allylamine were evidenced to survive over the photoadsorption process by vibrational analysis and by the reaction with ketene. CH3- groups were detected at low coverage, indicating anchoring of the organic moieties by the secondary (sec-) type carbon atoms, which were taken over by the primary (n-) type with increasing coverage. C-D bonds were detected after deposition on deuterium-terminated Si(111) upon incorporation of Si-terminating H into the hydrocarbon part of adsorbates. In the case of 1-butene, not only the C=C end but also the CH3- end of a molecule might attach on Si, resulting in emergence of adsorbates composed of CH2 groups. The newly obtained adsorbates are prospective as a material applied for nanolithography, fine electrochemistry, and nano-biotechnology. 相似文献
105.
Yamada T Shirasaka K Noto M Kato HS Kawai AM 《The journal of physical chemistry. B》2006,110(14):7357-7366
Grafting of unsaturated hydrocarbon moieties (-CH(2)-CH=CH(2), -CH=CH(2), -CH(2)-CH=CH-CH(3), and -CCH) by a C-Si covalent bond was attempted by the Grignard reaction on hydrogen-terminated Si(111) in tetrahydrofuran solutions. The product adsorbates were monitored by vibrational methods of high-resolution electron energy loss spectroscopy and multiple internal infrared reflection absorption spectroscopy, as well as Auger electron spectroscopy. The temperature and the period of reaction were adjusted so as to preserve the unsaturated carbon-carbon bonds. The -CH(2)-CH=CH(2) group was introduced by a mild reaction condition, with the reservation of the C=C double bond confirmed. The unsaturated bonds in -CH(2)-CH=CH-CH(3) and -CCH were also reserved. Only in the case of -CH=CH(2) was the reservation of the C=C double bond not realized. Unsaturated hydrocarbon moieties are applicable for further organic modification to introduce functional groups, and are prospective materials in nanofabrication and biological application on silicon wafer surfaces. 相似文献
106.
Taro Tsuji 《Colloid and polymer science》1926,39(2):110-112
Ohne Zusammenfassung 相似文献
107.
Background
DNA polymerase ε (Pol ε) is involved in DNA replication, repair, and cell-cycle checkpoint control in eukaryotic cells. Although the roles of replicative Pol α and Pol δ in chromosomal DNA replication are relatively well understood and well documented, the precise role of Pol ε in chromosomal DNA replication is not well understood. 相似文献108.
Taro Fukaya Hiroko Watando Shinetsu Fujieda Shioko Saya Cao Minh Thai Masaaki Yamamoto 《Polymer Degradation and Stability》2006,91(11):2549-2553
We have found that a reheating process for the products in the chemical recycling of rigid polyurethane foam by an extruder with diethanolamine as a decomposing agent is effective for improving the product stability. The product with stable viscosity was obtained by the reheating process at 175-200 °C for 2 h, regardless of the extruding condition. An amine adduct, which is an intermediate, was found to be the cause of instability of the discharged product from the extruder. At the initial stage of reheating, the intermediate decomposed, releasing toluenediamine, which promoted further decomposition of the discharged products. We have succeeded in controlling the quality of the recycled products. 相似文献
109.
An ideally (1x1)-CH(3)(methyl)-terminated Si(111) surface was composed by Grignard reaction of photochlorinated Si(111) and the surface structure was for the first time confirmed by Auger electron spectroscopy, low energy electron diffraction, high-resolution electron energy loss spectroscopy (HREELS), scanning tunneling microscopy (STM), and scanning tunneling spectroscopy (STS). HREELS revealed the vibration modes associated to the CH(3)-group as well as the C-Si bond. STM discerned an adlattice with (1x1) periodicity on Si(111) composed of protrusions with internal features, covering all surface terraces. The surface structure was confirmed to be stable at temperatures below 600 K. STS showed that an occupied-state band exists at gap voltage of -1.57 eV, generated by the surface CH(3) adlattice. This CH(3):Si(111)-(1x1) adlayer with high stability and unique electronic property is prospective for applications such as nanoscale lithography and advanced electrochemistry. 相似文献
110.
Pyridine N-imine complexes of methylcobaloxime, CH3Co(Hdmg)2(R1— C5HnN+N?H) (n = 4; R1 = H, 2-CH3, 3-CH3, 4-CH3: n = 3; R1 = 2,6-CH3), have been synthesized by the reaction of CH3Co(Hdmg)2S(CH3)2 with a pyridine N-imine which is generated from a pyridine, hydroxylamine-O-sulfonic acid and K2CO3. The reactions of CH3Co(Hdmg)2(C5H5N+N?H) with acid anhydrides form new methylcobaloxime complexes with N-substituted pyridine N-imines, CH3Co(Hdmg)2(C5H5N+N?R2) R2 = COPh, COMe, COEt). With maleic anhydride, (pyridine N-acryloylimine)carboxylic acid is formed. With acetylenedicarboxylic acid dimethyl ester, 1,3-dipolar cycloaddition of the ligand gives pyrazolo[1,5-a]pyridine-2,3-dicarboxylic acid dimethyl ester. 相似文献