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101.
Ritsuo Nishida Todd E. Shelly Kenneth Y. Kaneshiro 《Journal of chemical ecology》1997,23(10):2275-2285
Males of the Oriental fruit fly, Bactrocera dorsalis, are strongly attracted to and compulsively feed on a fragrant lei flower, Fagraea berteriana. A series of phenylpropanoid components, trans-3,4-dimethoxycinnamyl alcohol, its acetate, and trans-3,4-dimethoxycinnamaldehyde were characterized as male attractants. The alcohol stimulated the same level of feeding activity as methyl eugenol. Males that fed on flowers selectively converted the attractant components into trans-coniferyl alcohol and stored it in rectal glands. Males scented with the phenylpropanoids were more successful in mating than unfed males, indicating the advantage of acquiring the fragrance in mating success. 相似文献
102.
Several pharmacophagous insects have been shown to sequester specific kairomonal substances or their derivatives in their body tissues. Turnip sawflies,Athalia rosae, visit a plant,Clerodendron trichototmum (Verbenaceae), and feed voraciously on the leaf surface. Clerodendrins were characterized as the potent phagostimulants forA. rosae adults. The insect sequesters some of the analogs and becomes extremely bitter on its body surface. Some chrysomelid leaf beetles associated with cucurbitacins were found to store high concentrations of these bitter principles in their body. South American polyphagous beetles,Diabrotica speciosa andCerotoma arcuata, are strongly arrested by root components from the cucurbit plant,Ceratosanthes hilariana, and selectively accumulate 23,24-dihydrocucurbitacin D, effectively gaining bitterness. Similarly, four species of Asian pumpkin leaf beetles belonging to the genusAulacophora were shown to sequester the same compound in body tissue as the major bitter principle. Three phenylpropanoids closely related to methyl eugenol were found to accumulate in the rectal glands of the male Oriental fruit fly,Dacus dorsalis. One of the rectal gland components, 2-allyl-4,5-dimethoxyphenol was shown to be released in the air during courtship. In all of these cases, selectively sequestered compounds strongly deterred feeding by some predators, thus serving as allomones in this context. Kairomonal and pheromonal functions linked with allomonal sequestration by pharmacophagous feeding has also been suggested. 相似文献
103.
104.
Yabu T. Geshiro M. Kitamura T. Nishida K. Sawa S. 《Quantum Electronics, IEEE Journal of》2002,38(1):37-46
We propose a new element containing a two-mode nonlinear waveguide consisting of Kerr-like material for all-optical logic circuits. The proposed element, incorporated into the Mach-Zehnder interferometer, functions like a phase shifter. Although the optical waves propagating in the proposed element are monochromatic and identical in polarization, its function is insensitive to the relative phase difference between the incident beams. Using this element, we can realize various logic functions. In this paper, we demonstrate such logic circuits as inverters, distributors, and AND gates 相似文献
105.
Kohji Ohno Thomas Maschmeyer Sébastien Perrier 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(4):482-488
The generation of patterned surfaces with well‐defined nano‐ and microdomains is demonstrated by attaching core/shell, semisoft nanoparticles with narrow size distribution to microdomains of a gold‐coated silicon wafer. Near monodisperse nanoparticles are prepared using reversible addition‐fragmentation chain transfer (RAFT) polymerization, initiated from a silica surface, to prepare a polystyrene shell around a silica core. The particles are then used as‐prepared, or after aminolysis of the terminal thiocarbonyl group of the polystyrene shell, to give thiol‐terminated nanoparticles. When gold‐coated silicon wafers are immersed into very dilute suspensions of these particles (as low as 0.004 wt%), both types of particles are shown to adhere to the gold domains. The thiolated particles adhere selectively to the gold microdomains, allowing for microdomain patterning, while particles that contain the trithiocarbonate functionality lead to a much more even coverage of the gold surface with fewer particle aggregations. 相似文献
106.
Frictional anisotropy of oblique Ti nanocolumns grown by glancing angle deposition (GLAD) was investigated by ramp-scratch
experiments in forward (in the direction of the column tilt) and reverse (against the column tilt) directions using rectangular
and conical loading tips. Strong anisotropy in friction was generally observed, wherein the resistance or friction coefficient
in reverse scratching was higher than that in forward scratching, and the reverse resistance was sensitive to the tip shape.
In forward scratching, the nanocolumns bend with the column tilt direction, designated as the W-mode deformation. On the other
hand, in reverse scratching, the nanocolumns deflect against the column tilt in high normal force, designated as the A-mode
deformation. The deformation mode changes from the W-mode to the A-mode as the normal force increases in reverse scratching.
The mechanism of the frictional anisotropy was discussed on the basis of a simple deformation model of column by finite element
method. The anisotropy can be explained by the difference in the deformation mode. That is, compressive deformation in the
longitudinal direction and large deflection against the column tilt induce higher friction resistance in reverse scratching
than in forward scratching brought about by compliant bending deformation with the column tilt. 相似文献
107.
M. Nishida T. Shindo Y. Komatsu S. Okamoto M. Kaneiwa T. Nanmori 《Solar Energy Materials & Solar Cells》1997,48(1-4)
Annealing effects of the single-crystalline silicon solar cells with hydrogenated microcrystaline silicon (μc-Si : H) film were studied to improve the conversion efficiency. Boron-doped (p+) μc-Si : H film was deposited in a RF plasma enhanced chemical vapor deposition system (RF plasma CVD) on the rear surface of the cell. With the optimized annealing conditions for the substrate, the conversion efficiency of 21.4% (AM1.5, 25°C, 100 mW/cm2) was obtained for 5 × 5 cm2 area single crystalline-solar cell. 相似文献
108.
Bae J. Nozokido T. Shirai H. Furuya K. Nishida T. Mizuno K. 《Quantum Electronics, IEEE Journal of》1989,25(7):1591-1594
A modified current pulsed Q (EMQ)-switched CO2 laser which is Q -switched by a mechanical beam chopper in combination with a pulsed discharge current is discussed. The laser produces a very stable output with a peak power greater than 1 kW at a repetition rate of 1000 p.p.s. for all transitions in the P and R branches of the CO2 spectrum. A CH3F laser pumped by the EMQ-switched laser produces 496 μm radiation in a 6.5 W peak, 100 ns pulses at 500 p.p.s. in the lowest loss EH11 mode 相似文献
109.
N Uchida Y Takeda H Kasai K Hojo T Wada K Nishida R Maekawa K Sugita T Yoshioka 《Canadian Metallurgical Quarterly》1998,25(14):2267-2274
Augmented antitumor activity was demonstrated in combination chemotherapy of Nedaplatin (NDP) or Cisplatin (CDDP) with 5-fluorouracil (5-FU) against murine lung carcinoma and human squamous carcinoma from head and neck. Either NDP or CDDP (1/4 to 1 maximum tolerated dose; MTD) was injected once and 5-FU (1/16 MTD) was injected daily for five days via tail vein to tumor-implanted mice. The sequential administration of either NDP or CDDP prior to 5-FU (NF or CF therapy) showed severe body weight loss followed by the toxic death of tumor-bearing mice at the MTD of NDP or CDDP. In contrast, the reverse sequence of the treatment, that is, 5-FU prior to NDP or CDDP (FN or FC therapy), resulted in the synergistically enhanced inhibition of tumor growth and the prolonged survival in comparison with NDP, CDDP or 5-FU monotherapy. The antitumor activities of the combinations of CDDP with 5-FU was less than those of the combination of NDP with 5-FU. Especially, at the MTD of NDP in FN therapy, long-term tumor-free survival was frequently observed. Thus, FN therapy was thought to be the most efficient regimen in combination of NDP with 5-FU as a clinical therapy. 相似文献
110.
The mitogen-activated protein kinase (MAPK) superfamily comprises classical MAPK (also called ERK), c-Jun amino-terminal or stress-activated protein kinase (JNK or SAPK), and p38. Although MAPK is essential for meiotic processes in Xenopus oocytes and the spindle assembly checkpoint in Xenopus egg extracts, the role of members of the MAPK superfamily in M phase or the spindle assembly checkpoint during somatic cell cycles has not been elucidated. The kinase p38, but not MAPK or JNK, was activated in mammalian cultured cells when the cells were arrested in M phase by disruption of the spindle with nocodazole. Addition of activated recombinant p38 to Xenopus cell-free extracts caused arrest of the extracts in M phase, and injection of activated p38 into cleaving embryos induced mitotic arrest. Treatment of NIH 3T3 cells with a specific inhibitor of p38 suppressed activation of the checkpoint by nocodazole. Thus, p38 functions as a component of the spindle assembly checkpoint in somatic cell cycles. 相似文献