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271.
The 40S ribonucleoprotein particle in Escherichia coli cells, accumulated in the presence of a low concentration of chloramphenicol, lacks at least four ribosomal structural protein components which are present in the mature 50S ribosomal subunit. The 40S ribonucleoprotein prepared by exposing the 50S ribosomal subunit to a concentrated lithium chloride solution may also be deficient in the same protein components. 相似文献
272.
Mochizuki K Yamada T Shinohara M Yamanaka Y Kanazawa T 《Science (New York, N.Y.)》2008,321(5893):1194-1197
Subducting seamounts are thought to increase the normal stress between subducting and overriding plates. However, recent seismic surveys and laboratory experiments suggest that interplate coupling is weak. A seismic survey in the Japan Trench shows that a large seamount is being subducted near a region of repeating earthquakes of magnitude M approximately 7. Both observed seismicity and the pattern of rupture propagation during the 1982 M 7.0 event imply that interplate coupling was weak over the seamount. A large rupture area with small slip occurred in front of the seamount. Its northern bound could be determined by a trace of multiple subducted seamounts. Whereas a subducted seamount itself may not define the rupture area, its width may be influenced by that of the seamount. 相似文献
273.
In Okinawa, red soil runoff emerged as a social problem long ago, and many control measures have been adopted. However, their
effect has been gauged as insufficient. So, models to predict red soil runoff are required. Within this context, we have been
developing the suspended sediment concentration (SSC) analysis model. In this study, the SSC analysis model, a lumped storage-type
runoff model that includes a sediment runoff process, has been applied to two watersheds with different circumstances of land
use. In the application of this model, we tried to do a multi-objective optimization and examined some policies concerning
the choice of parameter sets. As a result, we were able to conclude that the SSC analysis model produced a good agreement
between the calculated value and the observed value. In multi-objective optimization, the relation between the root mean square
error (RMSE) of discharge and SSC became the Pareto relation. Moreover, it was recognized that, in taking into consideration
the viewpoint of the RMSE of sediment load and the total sediment load error, the optimization of discharge should be regarded
as important in choosing the set of parameters in an actual application. 相似文献
274.
275.
Kiyoshi Soyano Toshihiko Saito Masaki Nagae Kohei Yamauchi 《Fish physiology and biochemistry》1993,11(1-6):265-272
Blood and ovarian samples were collected at intervals of 4h prior to spawning time from medaka (Oryzias latipes) that were maturationally synchronized with artificial photoperiod (14h light: 10h dark). Plasma estradiol-17β (E2) levels increased rapidly from 16h before spawning and peaked at 8h before spawning. Follicle-enclosed oocytes (ovarian follicles) at different stages of development were isolated from the ovaries and used to study the in vitro effects of thyroid hormone (triiodothyronine; T3) on pregnant mare serum gonadotropin (GTH)-induced E2 production. GTH at a concentration of 100 IU/ml stimulated E2 production by ovarian follicles collected between 32 and 16h before spawning. At 32h before spawning, T3 (5 ng/ml) administered along with GTH (100 IU/ml) resulted in a 3.5 fold increase in E2 production, compared with GTH administered alone. These results suggest that T3 can act on ovarian follicles directly to modulate GTH-stimulated E2 production in the medaka. 相似文献