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1.
Namoi Shibasaki Ryousuke Obika Toshikuni Yonemoto Teiriki Tadaki 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,63(3):201-208
Suspension cultures of tobacco cells were studied using airlift and rotary-drum bioreactors. The effect of initial concentrations of a major substrate, sucrose, on the growth and production of a secondary metabolite, phenolic compounds, was investigated. The dry weights and total concentrations of the phenolic compounds increased with the initial sucrose concentration in both bioreactors. Both bioreactors were found to have the same tendency for the effect of initial sucrose concentration. The structured model, presented previously was modified by considering that sucrose was hydrolyzed to glucose and fructose by an enzymatic reaction. The previous and the new models were applied to the above two sets of experimental data obtained with two bioreactors, independently. The hydrolysis of sucrose was elucidated to contribute slightly to the overall kinetics of growth and secondary metabolite production in these cultures. Furthermore, the levels of shear damage in each bioreactor were quantitatively compared based on the death rate constant, ki, which is one of the model constants. 相似文献
2.
A theory recently developed by the present authors is applied to the study of the effect of elastic energy due to atomic size factor on the transformation behaviour of binary solid solutions. lt is found that elastic interaction energy (EIE), which is a part of the total elastic energy plays a key role in both ordering elastic interaction ordering (EIO) and spinodal decomposition. The present study gives a reasonable explanation to the historical dilemmas, "elastic energy paradox" and "atomic size factor paradox . By solving these confusing problems, the coexistence of ordering (EIO) and decomposition, which has been regarded as impossible by conventional theories. can be well understood. The mechanism is as follows: lowering of elastic energy demands EIO, and such an ordering provides a driving force for spinodal decomposition. Therefore, in alloys with large atomic size factor, spinodal decomposition is preceded and induced by ordering. Ordering and spinodal decomposition are thus closely related processes to each other 相似文献
3.
A theory of one-tape two-way one-head off-line linear-time Turing machines is essentially different from its polynomial-time counterpart since these machines are closely related to finite state automata. This paper discusses structural-complexity issues of one-tape Turing machines of various types (deterministic, nondeterministic, reversible, alternating, probabilistic, counting, and quantum Turing machines) that halt in linear time, where the running time of a machine is defined as the length of any longest computation path. We explore structural properties of one-tape linear-time Turing machines and clarify how the machines’ resources affect their computational patterns and power. 相似文献
4.
5.
Gary Brierley Marc Tadaki Dan Hikuroa Brendon Blue Charlotte unde Jon Tunnicliffe Anne Salmond 《河流研究与利用》2019,35(10):1640-1651
The granting of rights to the Whanganui River in 2017 emerged as an outcome of Tribunal hearings relating to breaches of the Treaty of Waitangi, signed between Māori chiefs and the British Crown in 1840. As this expression of a river as having legal personhood with rights reflects a distinctively Māori perspective upon river systems, it offers the prospect for a new era of sociocultural approaches to river management in Aotearoa New Zealand. Using the Whanganui River as a case study, this paper explores prospective geomorphic meanings of river rights. The paper asks, “What role can geomorphology play in identifying, articulating and protecting the rights of a river?” Ancestral Māori relations to the river based upon mutual codependence (reciprocity) are juxtaposed against geomorphic understandings of a river's agency as expressed through self‐adjustment, diversity of form, evolution, and catchment‐scale connectivities. Relations between river science and indigenous concepts of rivers, framed under the auspices of river rights, present opportunities for different approaches to river management. 相似文献
6.
Nandagopal Krishnadas; Tadaki Douglas K.; Lamerdin John A.; Serpersu Engin H.; Niyogi Salil K. 《Protein engineering, design & selection : PEDS》1996,9(9):781-788
The biological importance of Leu15 of epidermal growth factor(EGF) is suggested by its conservation through evolution, itscritical location in the domaindomain interface of EGFand its close proximity to Arg41, a residue that is crucialfor receptor binding and activation. Mutagenesis of Leu15 ofhuman EGF (hEGF) was employed to examine the role of this residuein the ligand-receptor interaction. The relative receptor affinitiesof the hEGF variants, as determined by radioreceptor competitionassays, varied depending on the amino acid substitution. TheL15F, L15W and L15V hEGF analogues had receptor affinities 45,26 and 18% respectively of wild type hEGF. The L15A and L15Ranalogues displayed receptor affinities of only 2.4 and 1.6%relative to wild type hEGF. No binding of the L15E analoguewas detected. The relative agonist activities, as measured byreceptor tyrosine kinase stimulation assays, generally followeda similar trend. The L15F, L15W and L15V analogues stimulatedthe receptor kinase to a level (Vmax) similar to that for wildtype hEGF. A striking difference was observed between the L15Aand L15R variants; although having similar binding affinities,the L15A mutant activated the receptor to only {small tilde}5%of the wild type Vmax in contrast to 53% for the L15R mutant1H-NMR analysis of the L15R and L15A mutants showed only minorstructural alterations that were not sufficient to account forthe dramatic losses in binding and agonist activities. The resultsindicate that both the size and hydrophobicity of the -branchedaliphatic side chain of Leu15 of hEGF are important in the formationof a catalytically active ligandreceptor complex. 相似文献
7.
Takahashi T. Sekiguchi T. Takemura R. Narui S. Fujisawa H. Miyatake S. Morino M. Arai K. Yamada S. Shukuri S. Nakamura M. Tadaki Y. Kajigaya K. Kimura K. Itoh K. 《Solid-State Circuits, IEEE Journal of》2001,36(11):1721-1727
A multigigabit DRAM technology was developed that features a low-noise 6F2 open-bitline cell with fully utilized edge arrays, distributed overdriven sensing for operation below 1 V, and a highly reliable post-packaging repair scheme using a stacked-flash fuse. This technology, which can be used to fabricate a 0,13-μm 180-mm2 1-Gb DRAM assembled in a 400-mil package, was verified using a 57.6-mm2, 200-MHz array-cycle, 256-Mb test chip with 0.109-μm2 cells 相似文献
8.
S. B. Ren T. Tadaki K. Shimizu X. T. Wang 《Metallurgical and Materials Transactions A》1995,26(8):2001-2005
Aging processes occurring in an Fe-1.83 wt pct C martensite at room temperature have been studied by electron diffraction,
assisted by transmission electron microscopy observation. Fourier analysis of diffuse scattering from the martensite suggested
that a spinodal decomposition occurred therein. The spinodally modulated microstructure was composed of a dominant wave with
a wavelength of about 1 nm and nondominant waves with longer wavelengths and was observed not to grow even after aging for
several months. The reason for the nongrowth may be that the coarsening was stopped by strong elastic interactions between
carbon-enriched and carbon-depleted regions. Furthermore, the tetragonality of the martensite was observed to remain constant
during aging, suggesting that carbon redistribution during spinodal decomposition occurred within one set of the octahedral
interstitial sitesO
z only.
formerly Visiting Researcher, The Institute of Scientific and Industrial Research, Osaka University 相似文献
9.
Structure-function analysis of a conserved aromatic cluster in the N- terminal domain of human epidermal growth factor 总被引:1,自引:0,他引:1
Murray MB; Tadaki DK; Campion SR; Lamerdin JA; Serpersu EH; Bradrick TD; Niyogi SK 《Protein engineering, design & selection : PEDS》1998,11(11):1041-1050
The importance of a cluster of conserved aromatic residues of human
epidermal growth factor (hEGF) to the receptor binding epitope is suggested
by the interaction of His10 and Tyr13 of the A-loop with Tyr22 and Tyr29 of
the N-terminal beta-sheet to form a hydrophobic surface on the hEGF
protein. Indeed, Tyr13 has previously been shown to contribute a
hydrophobic determinant to receptor binding. The roles of His10, Tyr22 and
Tyr29 were investigated by structure-function analysis of hEGF mutant
analogues containing individual replacements of each residue. Substitutions
with aromatic residues or a leucine at position 10 retained receptor
affinities and agonist activities similar to wild- type indicating that an
aromatic residue is not essential. Variants with polar, charged or
aliphatic substitutions altered in size and/or hydrophobicity exhibited
reduced binding and agonist activities. 1- Dimensional 1H NMR spectra of
high, moderate and low-affinity analogues at position 10 suggested only
minor alterations in hEGF native structure. In contrast, a variety of
replacements were tolerated at position 22 or 29 indicating that neither
aromaticity nor hydrophobicity of Tyr22 and Tyr29 is required for receptor
binding. CD spectra of mutant analogues at position 22 or 29 indicated a
correlation between loss of receptor affinity and alterations in hEGF
structure. The results indicate that similar to Tyr13, His10 of hEGF
contributes hydrophobicity to the receptor binding epitope, whereas Tyr22
and Tyr29 do not appear to be directly involved in receptor interactions.
The latter conclusion, together with previous studies, suggests that
hydrophobic residues on only one face of the N-terminal beta-sheet of hEGF
are important in receptor recognition.
相似文献
10.
Tadaki Miyoshi Keita Ushigusa Kouto Migita Masakatsu Tamechika Nobuko Tokuda Teruhisa Kaneda 《Journal of Materials Science》2008,43(1):203-206
Thermoluminescence of X-ray-irradiated CdS-doped glasses has been measured, and relation between thermoluminescence and induced
absorption in the X-ray-irradiated CdS-doped glasses has been investigated. The effect of thermal annealing and the X-ray
energy dependence of thermoluminescence is different from that on the induced absorption. Therefore, defects, which are responsible
for thermoluminescence, are considered to be different from those responsible for the induced absorption. 相似文献