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91.
92.
We hypothesized that initiation of ventilation in preterm lambs with high volumes would cause lung injury and decrease the subsequent response to surfactant treatment. Preterm lambs were randomized to ventilation for 30 min after birth with 5 ml/kg (VT5), 10 ml/kg (VT10), or 20 ml/kg (VT20) tidal volumes and then ventilated with approximately 10 ml/kg tidal volumes to achieve arterial PCO2 values of approximately 50 Torr to 6 h of age. VT20 lambs had lower compliances, lower ventilatory efficiencies, higher recoveries of protein, and lower recoveries of surfactant in alveolar lavages and in surfactant that had decreased compliances when tested in preterm rabbits than VT5 or VT10 lambs. Other lambs randomized to treatment with surfactant at birth and ventilation with 6, 12, or 20 ml/kg tidal volumes for 30 min had no indicators of lung injury. An initial tidal volume of 20 ml/kg decreased the subsequent response to surfactant treatment, an effect that was prevented with surfactant treatment at birth. 相似文献
93.
Tatsuyuki Kawamura Tomohiro Fukuhara Hideaki Takeda Yasuyuki Kono Masatsugu Kidode 《Personal and Ubiquitous Computing》2007,11(4):287-298
In this paper we propose an object-triggered human memory augmentation system named “Ubiquitous Memories” that enables a user
to directly associate his/her experience data with physical objects by using a “touching” operation. A user conceptually encloses
his/her experiences gathered through sense organs into physical objects by simply touching an object. The user can also disclose
and re-experience for himself/herself the experiences accumulated in an object by the same operation. We implemented a prototype
system composed basically of a radio frequency identification (RFID) device. Physical objects are also attached to RFID tags.
We conducted two experiments. The first experiment confirms a succession of the “encoding specificity principle,” which is
well known in the research field of psychology, to the Ubiquitous Memories system. The second experiment aims at a clarification
of the system’s characteristics by comparing the system with other memory externalization strategies. The results show the
Ubiquitous Memories system is effective for supporting memorization and recollection of contextual events. 相似文献
94.
Yuka Tarui Takumi Chinen Dr. Yoko Nagumo Dr. Takayuki Motoyama Dr. Toshiaki Hayashi Dr. Hiroshi Hirota Dr. Makoto Muroi Yasuyuki Ishii Hisae Kondo Prof. Dr. Hiroyuki Osada Prof. Dr. Takeo Usui 《Chembiochem : a European journal of chemical biology》2014,15(7):934-938
Terpendole E is first natural product found to inhibit mitotic kinesin Eg5, but its inhibitory mechanism remains to be revealed. Here, we report the effects of terpendole E and 11ketopaspaline (a new natural terpendole E analogue) on the Eg5–microtubule interaction and in several Eg5 mutants. 11‐Ketopaspaline is a shunt product from terpendole E, and it shows potent inhibitory activity against the microtubule‐stimulated ATPase activity of Eg5. Unlike other Eg5 inhibitors, such as S‐trityl‐L ‐cysteine (STLC) and GSK‐1, both terpendole E and 11‐ketopaspaline only partially inhibited Eg5–microtubule interaction. Furthermore, terpendole E and 11‐ketopaspaline inhibited several Eg5 mutants that are resistant to STLC (Eg5D130A, Eg5L214A) or GSK‐1 (Eg5I299F, Eg5A356T), but with the same extent of inhibition against wild‐type Eg5. Because Eg5D130A and Eg5L214A show cross‐resistance to most known Eg5 inhibitors, which bind the L5 loop, these results suggest that terpendole E and its analogues have a different binding site and/or inhibitory mechanism to those for L5 loop‐binding type Eg5 inhibitors. 相似文献
95.
INTRODUCTI0NUnsteadyphenomenaappearedinacentrifugalcompressorsystematlowflowratearecharacterizedbysurgeandrotatingstall.Thesurgeisknowntocauseoscillationswithlargeamplitudeofthefiowrateandthepressurerisethrough0utacompressorsys-tem.Ontheotherhand,ther0tatingstallcauseslocalflowoscillationsandappearsinsomepartsofacompressor,suchastheinducer,theimpellerandthediffuser-Sincetheydeterioratethecompressorperfor-manceands0metimesleadtothesystembreakd0wn,itisimportanttoknowthephysicalmechanismsofth… 相似文献
96.
The next-generation energy production systems are expected to be based on ocean thermal energy conversion (OTEC) and discharged thermal energy conversion (DTEC). These systems use a plate-type evaporator and ammonia or an ammonia/water mixture as a working fluid. It is important to clarify heat transfer characteristics for designing efficient power generation systems. Measurements of local boiling heat transfer coefficients and visualizations were performed for an ammonia/water mixture (z = 0.9) on a vertical flat plate heat exchanger at a range of mass fluxes (7.5-15 kg m−2 s−1), heat fluxes (15-23 kW m−2), and pressures (0.7-0.9 MPa). The results show that in the case of an ammonia/water mixture, the local heat transfer coefficients increase with an increase in the vapor quality and mass flux and decrease with an increase in the heat flux. The influence of the flow pattern on the local heat transfer coefficient is also observed. 相似文献
97.
Montagne K Huang H Ohara K Matsumoto K Mizuno A Ohta K Sakai Y 《Journal of Bioscience and Bioengineering》2011,112(5):485-490
Engineering liver tissue constructs with sufficient cell mass for transplantation implies culturing large numbers of hepatocytes in a reduced volume; however, providing sufficient oxygen to dense cell cultures is still not feasible using only conventional culture medium. Liposome-encapsulated hemoglobin (LEH), an oxygen-carrying blood substitute originally designed for short-term perfusion, may be a good candidate as an oxygen carrier to cultured liver cells. In this study, we investigated the feasibility of maintaining long term hepatocyte cultures using LEH. Primary fetal and adult rat liver cells were directly exposed to LEH for 6 to 14 days in static culture or in a perfused flat plate bioreactor. The functions and viability of adult rat hepatocytes exposed to LEH were not adversely affected in static monolayer culture and were even improved in the bioreactor. However, some cytotoxicity of LEH was observed with fetal rat liver cells after 4 days of culture. LEH, though a suitable oxygen carrier for long-term culture of mature hepatocytes, is not suitable in its present form for perfusing fetal hepatocyte cultures in direct contact with the liposomes; either the LEH will have to be made less toxic or a more sophisticated bioreactor that prevents the direct contact between hepatocytes and perfusates will have to be designed if fetal cells are to be used for liver tissue engineering. 相似文献
98.
Unno Y 《Applied optics》2011,50(3):271-281
Theoretical modeling of a slit-scan-type aerial image measurement sensor used for optical lithography is presented. Slit transmission properties are fully represented by the slit transfer function in terms of incident and scattering angles of light, which is then incorporated into the scheme of a partially coherent imaging formula to obtain an expression for image profiles measured by slit scanning. As an exemplary case, we analyze the influence of a 100 nm width slit used in an ArF lithography system. To understand the mechanism of image profile changes by slit transmission, we focus on frequency transfer characteristics of sinusoidal patterns. 相似文献
99.
100.
Room-temperature tensile property and fracture mode of B2-type polycrystalline CoTi intermetallic compound was studied as functions of microstructure and environment. Using a hot-rolled CoTi sheet, various microstructures were prepared by different heat treatments and pre-straining. Tensile elongation as well as ultimate tensile strength (UTS) of specimens deformed in vacuum (i.e. intrinsic tensile elongation and strength) depended on microstructure. The hot-rolled and recovered specimens showed higher elongation and tensile strength than the fully-annealed and aged specimens. Also, the pre-strained specimen showed the improved elongation and UTS in comparison with the fully-annealed specimen. On the other hand, tensile elongation and UTS of the specimens deformed in air were lower than those of the specimens deformed in vacuum, irrespective of microstructure. The extent of embrittlement was lower in the hot-rolled, recovered and pre-strained specimens than in the fully-annealed and aged specimens. SEM observation for the hot-rolled and recovered specimens showed that the quasi-cleavage fracture mode was dominant irrespective of testing environment. However, the fully-annealed, aged and pre-strained specimens consisting of recrystallized grains exhibited quasi-cleavage fracture mode mixed with intergranular fracture mode. The results showed that not only the intrinsic room-temperature tensile properties but also the environmental embrittlement of CoTi intermetallic compound depended upon lattice defects (such as dislocations and vacancies) in addition to grain size and morphology. 相似文献