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91.
Tripathi Laxmi Narayan Praveena M. Johns Ben Basu Jaydeep Kumar 《Plasmonics (Norwell, Mass.)》2018,13(5):1811-1816
Plasmonics - Nanoantenna-enhanced ultrafast emission from colloidal quantum dots as quantum emitters is required for fast quantum communications. On-chip integration of such devices requires a... 相似文献
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Doubling of the current atmospheric CO2 concentration, and an increase in global mean annual temperatures of 1.5–6 °C, have been predicted to occur by the end of this century. Whilst the separate effects of CO2 and temperature on plant–insect interactions have been examined in a number of studies, few have investigated their combined impact. We carried out a factorial experiment to explore the effect of a doubling of CO2 concentration and a 3 °C temperature increase on the development of a complete generation of the leaf‐miner, Dialectica scalariella, in the host plant Paterson's Curse, Echium plantagineum. Elevated CO2 increased biomass, reduced leaf N and increased C:N ratios in the host plants. Leaf thickness also increased under elevated CO2, but only in the high‐temperature treatment. Female D. scalariella did not discriminate between plants grown at the different CO2 levels when ovipositing, despite the reduction in foliage quality under elevated CO2. Overall, the negative response of D. scalariella to elevated CO2 was greater than for many species of free‐living insects, presumably because of the limited mobility imposed by the leaf‐mining habit. Development was accelerated at the high temperature and slowed under elevated CO2. The net result was a reduction in development time of ~14 days in the elevated CO2/high temperature treatment, compared to the ambient CO2/low temperature treatment. Larval survivorship and adult moth weight were both affected by a significant interaction between CO2 and temperature. At the low temperature, CO2 had little effect on survivorship, but at the high temperature, survivorship was significantly reduced under elevated CO2. Similarly, elevated CO2 had a stronger negative effect on adult moth weight when combined with the high‐temperature treatment. A possible explanation for these results is that the high temperature accelerated insect development to such an extent that the larvae did not have sufficient feeding time to compensate for the poorer quality of the foliage. The frequency with which interactions between CO2 and temperature affected both plant and insect performance in this study highlights the need for caution when predicting the effects of future climate change on plant–insect interactions from single‐factor experiments. 相似文献
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The component sterols, alcohols, hydrocarbons, monocarboxylic, α,ω-dicarboxylic and α- and ω-hydroxy acids from the leaves and roots of the tropical seagrass Thallassia hemprichii are reported. The leaves contained significant concentrations of cholest-5-en-3β-ol, a sterol not normally detected in either higher plants or seagrasses. The lower abundance of polyunsaturated fatty acids found in both the leaves and roots compared to other seagrass species may be a result of the warmer waters from which this species was collected. Solvent-extractable, long-chain (> C22)α,ω-diacids, α- and ω-hydroxy and monocarboxylic acids were also isolated from the leaves. The distribution pattern of these lipids should enable these components along with other distinctive components to be used as chemical markers for this seagrass. 相似文献
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DALDINIA CONCENTRICA ATTACKING THE WOOD OF FRAXINUS EXCELSIOR 总被引:1,自引:0,他引:1
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Airway epithelia play a crucial role in protecting the lung from the external environment. Ciliated airway epithelial cells contribute to mucociliary transport systems via ciliary beating and electrolyte transport mechanisms to defend against respiratory tract infection. Both of these activities are regulated by nitric oxide (NO)-dependent mechanisms. To better understand the role of the NO-cGMP signal transduction cascade in these responses, we investigated the localization of endothelial nitric oxide synthase (eNOS), soluble guanylyl cyclase (sGC), cGMP-dependent protein kinase (PKG) I-alpha, and PKG I-beta in the tracheas and lungs of normal rats by immunohistochemistry. Mouse anti-eNOS, rabbit anti-sGC, PKG I-alpha, and PKG I-beta antibodies were used. Strong immunostaining for eNOS was detected in ciliated tracheal, bronchial, and bronchiolar epithelia, in Clara cells, and in Type II alveolar cells. The pattern of sGC and PKG I-beta immunostaining showed striking parallels with that of eNOS staining. No staining was detectable in ciliated epithelium with the anti-PKG I-alpha antibody. Taken together, these observations suggest that PKG I-beta might transduce NO-sGC signaling into biological responses in ciliated respiratory epithelia.(J Histochem Cytochem 47:1369-1374, 1999) 相似文献