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Male moths locate conspecific females by pheromone‐induced upwind flight maintained by detecting a visual flow, termed optomotor anemotaxis. Their behavioural pattern is characterized by an upwind surge in response to a pheromone stimulus and crosswind casting after odour loss, which is considered to be reset and restarted on receipt of another pheromone pulse. However, pheromone‐stimulated males of the potato tuberworm moth Phthorimaea operculella exhibit a series of short and straight intermittent flights, or hops, when moving upwind. It is unclear whether they navigate by employing the same behavioural pattern and wind detection mechanism as that used by flying moths. To analyze odour‐modulated anemotaxis in male potato tuberworm moths, a flat wind tunnel is constructed to give regular odour stimuli to an insect regardless of its location. Moths are subjected to pheromone pulses of different frequencies to test whether they show a behavioural pattern that is reset and restarted by a pheromone pulse. Moths on the ground are also subjected to crosswind shear to examine their detection of wind direction. Path analyses reveal that males surge upwind when they receive a pheromone pulse and exhibit casting by successive hops when they lose odour. This behavioural pattern appears to be similar to that of flying moths. When the direction of the airflow is switched orthogonally, males adjust their course angle accordingly when they are on the ground. It is suggested that, instead of optomotor anemotaxis, this ‘aim‐then‐shoot’ system aids the detection of wind direction, possibly by mechanosensory means.  相似文献   
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The phylogeny of Colocasiomyia (Drosophilidae) is analysed using data for 70 morphological characters, many of which are re‐evaluated from or added to those used previously, for an expanded taxon sample of 24 Colocasiomyia ingroup species. A special focus is put on three species, of which two have remained unresolved for their relationships to other Colocasiomyia species, and the other is a newly discovered species. The analysis results in a single, most parsimonious cladogram, in which a clade comprising the three focal species is recognized along with other clades recovered for the known species groups of Colocasiomyia. Based on this, a new species group—the gigantea group—is established, including Colocasiomyia gigantea (Okada), C. rhaphidophorae Gao & Toda, n.sp. and C. scindapsae Fartyal & Toda, n.sp. These species of the gigantea group breed on inflorescences/infructescences of the subfamily Monsteroideae (Araceae) exceptionally among Colocasiomyia species, most of which use plants of the subfamily Aroideae as their hosts. Colocasiomyia gigantea uses Epipremnum pinnatum (L.) Engler, C. rhaphidophorae uses Rhaphidophora hookeri Schott and C. scindapsae uses Scindapsus coriaceus Engler as their hosts. The host plants of the gigantea group are epiphytes and differ in the structure of spadix and the fruiting process from those of the Aroideae. To understand how the species of the gigantea group adapt to properties of their host plants, their reproductive ecology—most intensively that of C. gigantea—is investigated. The lifecycle of C. gigantea is characterized by its relatively slow embryonic development (taking approximately 6 days), the very long duration of the full‐grown first instar within the egg capsule (approximately three months) until dehiscence of host infructescence, and its relatively fast larval and pupal development (taking approximately 11 or 12 days). Some morphological adaptations and the reproductive strategy in terms of ‘egg size vs. number’ trade‐off are discussed in relation to their reproductive habits and peculiar lifecycles.  相似文献   
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Glabridin is the main ingredient in hydrophobia fraction of licorice extract affecting on skins. In this study, we investigated inhibitory effects of glabridin on melanogenesis and inflammation using cultured B16 murine melanoma cells and guinea pig skins. The results indicated that glabridin inhibits tyrosinase activity of these cells at concentrations of 0.1 to 1.0 μg/ml and had no detectable effect on their DNA synthesis. Combined analysis of SDS-polyacrylamide gel electrophoresis and DOPA staining on the large granule fraction of these cells disclosed that glabridin decreased specifically the activities of Tl and T3 tyrosinase isozymes. It was also shown that UVB-induced pigmentation and erythema in the skins of guinea pigs were inhibited by topical applications of 0.5% glabridin. Anti-inflammatory effects of glabridin in vitro were also shown by its inhibition of superoxide anion productions and cyclooxygenase activities. These data indicated that glabridin is a unique compound possessing more than one function; not only the inhibition of melanogenesis but also the inhibition of inflammation in the skins. By replacing each of hydroxyl groups of glabridin with others, it was revealed that the inhibitory effect of 2′-O-ethyl glabridin was significantly stronger than that of 4′-O-ethyl-glabridin on melanin synthesis in cultured B16 cells at the concentration of 1.0 mg/inl. With replacement of both of two hydroxyl groups, the inhibitory effect was totally lost. Based on these data, we concluded that two hydroxyl groups of glabridin are important for the inhibition of melanin synthesis and that the hydroxyl group at the 4’ position of this compound is more closely related to melanin synthesis.  相似文献   
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ABSTRACT. The photosynthetic protozoon Euglena gracilis, accumulated a large amount of trehalose in the cells under salt or osmotic stresses. Radioactivity of [14C] paramylon, a β-1,3-polyglucan which was stored in the cells of E. gracilis. was degraded rapidly and this radioactivity was almost stoichiometrically incorporated into trehalose. The interconversion of trehalose from paramylon by salt or osmotic stresses was dependent on the concentrations or osmotic pressures, suggesting that E. gracilis accumulate trehalose as an osmoprotectant. After the removal of salt or osmotic stresses, trehalose was gradually degraded, however, it was not converted into paramylon.  相似文献   
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Background: Restoration of virus-specific immunity by virus specific T cells (VSTs) offers an attractive alternative to conventional drugs, and can be highly effective in immunocompromised patients, including hematopoietic stem cell transplant (HSCT) recipients. However, conventional VSTs manufacture requires preparation of specialized antigen-presenting cells (APCs), prolonged ex vivo culture in serum-containing medium and antigen re-stimulation with viruses or viral vectors to provide viral antigens for presentation on APCs. Methods: To simplify this complex process, we developed a method to generate multiple VSTs by direct stimulation of peripheral blood mononuclear cells (PBMCs) with overlapping peptide libraries in serum-free medium. Results: We generated VSTs that targeted seven viruses (cytomegalovirus [CMV], Epstein-Barr virus [EBV], adenovirus [AdV], human herpesvirus 6 [HHV-6], BK virus [BKV], JC virus [JCV] and Varicella Zoster virus [VZV]) in a single line. The phenotype, growth and specificity of multiple VSTs produced in serum-free medium were equivalent to those generated in conventional serum-containing medium. Discussion: The use of serum-free medium allows this approach to be readily introduced to clinical practice with lower cost, greater reproducibility due to the absence of batch-to-batch variability in serum and without concerns for infectious agents in the serum used. This simplified approach will now be tested in recipients of Human Leukocyte Antigen (HLA)–matched sibling HSCT.  相似文献   
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Abstract.  Although the effects of temperature on insect behaviours are studied frequently, few studies report on the relationship between temperature and anti-predator behaviours. A negative relationship between ambient temperature and the intensity of death-feigning is found in adults of two seed beetle species, Callosobruchus maculatus (F.) and C. chinensis (L.) (Coleoptera: Bruchidae). Two traits representing the intensity of immobility, the frequency and the duration of death-feigning, are measured at different temperatures. Almost all adults feign death at 15 °C, but the frequency of death-feigning decreases at higher temperatures in C. maculatus , whereas all C. chinensis adults show this behaviour at 15 and 20 °C and almost all show it at 25 °C, but the frequency of death-feigning decreases at 30 and 35 °C. The difference between the two species might be due to the specific strain of each species used in the experiment. The duration of death-feigning is correlated negatively with the increase in ambient temperature in both species. The frequency at which adults feigned death is higher in females than in males in both species, but the duration of death-feigning is higher in females than in males only in C. maculatus . The relationships between temperature and death-feigning behaviours are discussed from physiological and ecological viewpoints.  相似文献   
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ABSTRACT. Copulatory behaviour of the potato tuber moth, Phthorimaea operculella , was observed in a small glasshouse. The behavioural chain is started by the female 'calling'. Males responded to the female's sex pheromone by searching in her vicinity. When the males 'recognized' the female, they attempted copulation. This behaviour was released, however, by a wide variety of models, including dried whole male and female bodies, similarly sized rolls of paper with male or female wings attached, rolls of paper covered in wing scales, and even flat surfaces covered in wing scales (provided the surface was much larger than a moth). It is concluded that the mechanical stimulus from the scales is an important stimulus for evoking copulation.  相似文献   
9.
ABSTRACT. Pupation site preference and body orientation of potato tuber moth larvae, Phthorimaea operculella Zeller (Geleehiidae), were examined in the laboratory. The larvae preferred a dry, enclosed, dark place as their pupation site. Dryness was the strongest of the three categories of stimulus; the second was stimuli evoking thigmotaxis; the third was darkness. Having selected a pupation site, a larva oriented its head to the open side of the site. If two or more openings were present, final orientation was influenced by light and gravity. These preferences and orientation habits enhance pupal protection, and the ultimate successful exit of the adult pupation crevices.  相似文献   
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ABSTRACT. A novel combination of adaptations resulting from sperm competition is demonstrated for the tree cricket Truljalia hibinonis (Matsumura) (Podoscirtinae: Gryllidae: Orthoptera). 87.5% of the semen of previous males is displaced onto the penis of the copulating male and is removed at the end of copulation. Semen thus removed is ingested during post-copulatory oro-genital grooming. No overt morphological adaptations for sperm removal were observed and, on the basis of anatomical evidence, it is suggested that rivals' semen is flushed out of the female?s sperm storage organ by the semen of the last male.  相似文献   
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