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831.
832.
Katsuhiro Nishiyama Jiro Okada Yoshihiro Toh 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(9):963-971
The behavioral responses to attractive and aversive odors were examined in blinded adult male cockroaches under tethered-walking
conditions. A sex pheromone-like stimulant derived from adult virgin females and artificially synthesized limonene were used
as attractive and aversive odor sources, respectively. When a searching animal was stimulated with the attractive female-derived
odor, the horizontal deflections of both the antennae were increased, and in most cases the vertical antennal positions were
shifted downward. The stimulation also significantly decreased the walking speed of the animal. These behavioral changes imply
a careful search in the immediate surroundings. The aftereffect of the sex pheromone was more pronounced on locomotion than
on antennal movement. On the other hand, stimulation with the aversive odor (limonene) tended to suppress active antennal
movement, and also increased the walking speed. Immediately after the withdrawal of the aversive odor, the active movement
of the antennae was resumed, and the walking speed rapidly decreased to a level approximately the same as that of the control
period. These results indicate that the responses to the qualitatively opposite types of odor are reciprocal to each other
with regard to both antennal movement and locomotion. 相似文献
833.
d-Xylose, d-arabinose, and d-ribose were each treated with 2,2-dimethoxypropane in N,N-dimethylformamide containing a trace of p-toluenesulfonic acid. d-Xylose gave 3,5-O-isopropylidene-d-xylofuranose, 1,2:3,5-di-O-isopropylidene-α-d-xylofuranose, 1,2-O-isopropylidene-α-d-xylopyranose, and two acyclic di-O-isopropylidene derivatives. d-Arabinose gave the known 3,4-O-isopropylidene-β-d-arabinopyranose and 1,2:3,4-di-O-isopropylidene-β-d-arabinopyranose. d-Ribose gave 2,3-O-isopropylidene-d-ribofuranose almost exclusively. 相似文献
834.
Takashi Masaki Katsuhiro Osumi Kazunori Takahashi Kazuhiko Hoshizaki Kenji Matsune Wajirou Suzuki 《Ecological Research》2007,22(5):724-734
In a temperate riparian forest, the effects of substrate types, canopy gaps and conspecific seedfall density were investigated
on the seed-to-seedling process for the five dominant species (Aesculus turbinata, Fagus crenata, Acer mono, Pterocarya rhoifolia and Cercidiphyllum japonicum). Densities of seedfall and subsequent seedling recruits were measured in the stand over a period of 6 years. A model assuming
that local density of seedling recruits is proportional to seedfall density in the preceding year significantly explained
a spatial variation in seedling recruits for all species. Several environmental factors were then added. Substrate composition
had a positive effect on P. rhoifolia and C. japonicum. P. rhoifolia was favored by gravel substrate, which also explained the adult distribution of this species in this forest. C. japonicum appeared to be facilitated by a mineral-soil substrate. However, the distributions of this substrate and adults of C. japonicum did not follow each other closely. A. mono was negatively affected by gaps, and F. crenata was negatively affected by conspecific seedfall density. In contrast, A. turbinata was not significantly affected by any of the environmental factors tested. The microenvironmental heterogeneity in this forest
explained species coexistence to a limited extent in the context of seed-to-seedling processes. Performances at later stages
of the life-cycle and/or catastrophic disturbances (e.g. landslides) might have a stronger influence on species coexistence
in this forest. 相似文献
835.
Y Kiso Y Fujiwara T Kimura A Nishitani K Akaji 《International journal of peptide and protein research》1992,40(3-4):308-314
An efficient method for solid phase peptide synthesis was developed, which consists of N alpha-selective deprotection by dilute methanesulfonic acid, in situ neutralization and rapid coupling reaction using benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate (BOP) or 2-(benzotriazol-1-yl)oxy-1,3- dimethylimidazolidinium hexafluorophosphate (BOI) reagent. Selective removal of the N alpha-Boc group by dilute methanesulfonic acid was of more advantage than removal by TFA in terms of stability of semipermanent protecting groups and suppression of undesired side reactions. The use of in situ neutralization and rapid coupling method reduced intramolecular aminolytic cyclization by shortening exposure of the deprotected nucleophilic amino group. A successful synthesis of porcine brain natriuretic peptide (pBNP) has been achieved using this efficient solid phase peptide synthesis scheme. 相似文献