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排序方式: 共有147条查询结果,搜索用时 15 毫秒
1.
T Ganbo K Hisamatsu H Inoue A Mizukoshi R Goto Y Murakami 《Canadian Metallurgical Quarterly》1995,33(4):199-202
The effects of leukotrienes C4 and D4 on ciliary activity of human paranasal sinus mucosa were investigated in vitro. Normal mucosa was surgically obtained from human paranasal sinuses and incubated in the form of tissue culture. Ciliated cells were magnified under an inverted microscope, and ciliary activity was photoelectrically measured. LTD4 progressively inhibited ciliary activity, and showed a more potent effect on ciliary activity compared to LTC4. The concentrations of LTC4 and LTD4 in the incubation medium were determined by radioimmunoassay when the mucosa was incubated with 10(-8) M LTC4. The concentration of LTD4 gradually increased and after 90 min reached the maximum of 0.71 x 10(-8) M, while that of LTC4 was reduced to about 10% of its initial concentration within 60 min. These results suggested the possible conversion of LTC4 to LTD4 on the mucosa, and that LTC4 can inhibit ciliary activity by means of LTD4. 相似文献
2.
We constructed a probabilistic simulator that allows all the events in population dynamics such as death, birth, mutation,
and suppression/stimulation to be described by probabilistic rules. The simulator also facilitates a lattice used for expressing
distribution and diversity (number of distinct strains) of quasispecies. The simulator is used to investigate the diversity
threshold in HIV and T-cell interaction.
This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献
3.
Effects of support and additive on oxidation state and activity of Pt catalyst in propane combustion 总被引:1,自引:0,他引:1
The effects of support and additive on the oxidation state and catalytic activity of Pt catalyst in the low temperature propane combustion were systematically investigated on Pt/MgO, Pt/Al2O3 and Pt/SiO2–Al2O3. The catalytic activity varied much with both support materials and additives. The catalyst on the more acidic support showed higher activity, and the catalytic activity on every support materials increased as the electronegativity of additives increased, while some additives decreased the activity. The oxidation state of platinum, estimated by white line intensity of Pt LIII-edge XANES spectrum, also varied with the support and additives, and additives with higher electronegativity greatly prevented the platinum from its oxidation under oxidising atmosphere. Among almost all the catalysts with various supports and various additives, a clear relationship was observed between the oxidation state of platinum and the catalytic activity; the more metallic platinum showed higher activity. Thus, it was concluded that the total electrophilic/electrophobic property derived from those of the support and additive controls the oxidation state of platinum, which intensively affects the catalytic activity; i.e. higher electrophilic property provides less oxidised platinum, resulting in high catalytic activity. The mechanism of this effect was also discussed on the basis of thermochemical data, and it was proposed that the electrophobic materials promote the noble metal oxidation since the noble metal oxo-anion such as PtOδ− is more stabilised with electrophobic cation. 相似文献
4.
Yoshiteru Ishida 《Artificial Life and Robotics》2008,12(1-2):125-128
Antibodies, among other things, are important components of the immune system. This paper proposes using the specific recognition
capability exhibited by antibodies for computation, in particular, for solving the stable marriage problem, which has been studied as a combinatorial computational problem. Antibody-based computation is proposed by integrating the
recognition capabilities of antibodies. The computation is carried out on an array form that is suitable not only for expressing
stable marriage problems, but also for further integration to antibody microarrays.
This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January
25–27, 2007 相似文献
5.
Hans Haucke Yoshiteru Maeno Paul Warkentin John Wheatley 《Journal of Low Temperature Physics》1981,44(5-6):505-533
Time-dependent thermal convection can occur in a unity-aspect-ratio Rayleigh-Beard convection cell containing a dilute solution of 3He in superfluid 4He when the fluid is heated from above. Results are presented primarily for a 0.24 mole % He solution at 0.925 K. Means is provided for introducing heat at the top and separately for a central plug and an outer ring such that both are at a constant temperature gDT above the bottom. A critical temperature difference T
cfor convection can be defined above which both steady and time-dependent convection occur. The time-dependent effects include a region of T. near T
cand characterized only by excessive noise, a region of somewhat higher T where there are intermittent major changes in the plug heating rate with a time distribution like that for random events, and a region at still higher T where periodic but nonsinusoidal variation of the heat flow is observed. When a long enough time, several months, has elapsed after cooling down the apparatus, time-dependent states no longer occur, and the heat flow above T
cis limited to steady convection. Briefly raising the temperature of the apparatus to 77 K is sufficient to restore the possibility of time-dependent states. 相似文献
6.
Micro-scale textures may be engineered into surfaces for lubrication performance improvement. It is expected that a carefully
chosen texture helps retain lubricant and enhances the hydrodynamic effect at the interface. The concept of model-based virtual
texturing enables textured surfaces to be generated and “tested” through numerical simulations. This paper reports virtual
texturing and simulation of a group of textured surfaces in a lubricated concentrated contact. The focus of the study is on
the selection of texture distribution patterns based on their lubrication performance. Patterns of fishbone, sinusoidal, triangular,
and honeycomb distributions have been investigated. The effects of texture direction, orientation angle, feature continuity,
and aspect ratio are also studied. The results indicate that, for the given material and geometry system under the given conditions
in the present work, the textures generating the strongest hydrodynamic lifting are short grooves with a small aspect ratio
and sinusoidal waves of a small wavelength/amplitude ratio propagating in the motion direction. 相似文献
7.
Motonaka Kuroda Yumiko Kato Junko Yamazaki Naoko Kageyama Toshimi Mizukoshi Hiroshi Miyano Yuzuru Eto 《Food chemistry》2012
The determination of the kokumi peptide, γ-glutamyl-valyl-glycine (γ-Glu-Val-Gly) in raw scallop and processed scallop products was carried out using high pressure liquid chromatography–tandem mass spectrometry (LC/MS/MS). The detection of γ-Glu-Val-Gly was achieved using a multiple reaction monitoring (MRM) method. The optimised condition enabled the precise determination of γ-Glu-Val-Gly. Raw scallop contained 0.08 μg/g γ-Glu-Val-Gly, and the γ-Glu-Val-Gly levels in processed scallop products, such as dried-scallop and scallop extract, were measured to be 0.64 and 0.77 μg/g, respectively. This is the first report to confirm the existence of γ-Glu-Val-Gly in foodstuff. 相似文献
8.
Jiangfeng Ni Yoshiteru KawabeMasanori Morishita Masaharu WatadaTetsuo Sakai 《Journal of power sources》2011,196(19):8104-8109
Olivine lithium manganese phosphate (LiMnPO4) becomes research focus because of its high energy density and improved thermal stability. However, its application in lithium ion batteries suffers severely from poor electrochemical activity due to low conductivity and structural instability upon the charge and discharge process. By applying a high-energy ball-milling method we succeed in improving the capacity delivery and rate capability. LiMnPO4 materials ball-milled without or with acetylene black are able to deliver a high capacity of 135 and 127 mAh g−1, respectively, more than 50% greater than the pristine one. Particularly, the latter also shows an improved discharge plateau and stable cyclability. High-energy synchrotron radiation X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, laser particle analysis, and galvanostatic charge and discharge are employed to understand the effect of ball-milling on the LiMnPO4 material. 相似文献
9.
10.
Distributed intrusion detection systems have several advantages over centralized systems, such as scalability, adaptability, and fault tolerance. A current research topic in distributed systems is self-monitoring to identify corrupted intrusion detection systems. One way of self-monitoring is for intrusion detection systems to check each other. As we describe herein, this can be done by mobile agents using an immunity-based diagnostic method modeled on idiotypic network theory. In simulations, the credibility of normal intrusion detection systems remained near 1, while it fell to about 0 for corrupted intrusion detection systems, thus enabling identification of the latter. We also confirmed what effects some parameters have on the diagnostic capability.This work was presented, in part, at the 8th International Symposium on Artificial Life and Robotics, Oita, Japan, January 24–26, 2003 相似文献