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61.
Molecular Biology Reports - Sesame is an ancient oilseed crop, known for its high oil content and quality. Its sensitivity to drought at early seedling stage is one of the limiting factors...  相似文献   
62.
Journal of Plant Growth Regulation - The field experiment was conducted to investigate the effects of applying urea with nitrification inhibitor (NI) (Nitrapyrine) alone or in combination with...  相似文献   
63.
生物入侵过程中的植物-土壤反馈:一种入侵植物的凋落物分解对其本地近缘植物的影响 植物入侵可通过正或负的植物-土壤反馈效应改变土壤的生物和非生物性质,从而影响入侵栖息地的土壤理化性质。许多入侵物种的凋落物分解可增加土壤养分,降低本地植物多样性,并导致进一步的植物入侵。关于入侵植物凋落物在不同土壤类型及深度分解及反馈效应的研究依然很少。本研究旨在明确入侵植物南美蟛蜞菊(Sphagneticola trilobata)凋落物在不同土壤类型和不同土壤深度条件下的分解情 况及其对本地近缘植物蟛蜞菊(S. calendulacea)生理生长的影响。将装有南美蟛蜞菊凋落物的尼龙袋加入到不同深度(即0、2、4 和6 cm)的砂土、营养土和粘土中,经6个月的分解后,回收凋落物袋并计算分解速率,随后在凋落物分解处理后的土壤中种植本地蟛蜞菊,并在生长期结束时测量其生理生态指标。研究结果表明,所有处理土壤类型中,凋落物在土壤深度为2和4 cm处分解后显著增加了土壤养分,而对本 地蟛蜞菊的叶片叶绿素、叶氮含量等生长指标表现为负效应。因此,入侵植物南美蟛蜞菊凋落物分解对土壤养分表现为正的反馈效应,而对本地植物蟛蜞菊的生长表现为负效应。我们的研究结果还表明,入侵植物的凋落物分解对土壤和本地物种的影响还因凋落物分解所在的土壤深度而显著不同。未来的研究应侧重于入侵栖息地中更多本地和入侵物种的植物-土壤反馈效应,以及更多土壤类型和土壤深度的入侵植物凋落物效应。  相似文献   
64.
Biological Invasions - What kind of genetic structure helps the rapid range expansion of the invasive species is fundamental to understand spread of invasion. The House crow (Corvus splendens), an...  相似文献   
65.
Endocytosis plays key roles during infection of plant-pathogenic fungi, but its regulatory mechanisms are still largely unknown. Here, we identified a putative endocytosis-related gene, PAL1, which was highly expressed in appressorium of Magnaporthe oryzae, and was found to be important for appressorium formation and maturation. Deletion of PAL1 significantly reduced the virulence of M. oryzae due to defects in appressorial penetration and invasive growth in host cells. The Pal1 protein interacted and colocalized with the endocytosis protein Sla1, suggesting it is involved in endocytosis. The Δpal1 mutant was significantly reduced in appressorium formation, which was recovered by adding exogenous cAMP and 3-isobutyl-1-methylxanthine (IBMX). Moreover, the phosphorylation level of Pmk1 in Δpal1 was also reduced, suggesting Pal1 functions upstream of both the cAMP and Pmk1 signalling pathways. As a consequence, the utilization of glycogen and lipid, appressorial autophagy, actin ring formation, localization of septin proteins, as well as turgor accumulation were all affected in the Δpal1 mutant. Taken together, Pal1 regulates cAMP and the Pmk1 signalling pathway for appressorium formation and maturation to facilitate infection of M. oryzae.  相似文献   
66.

Surface plasmon polariton (SPP) waves are the most extensively studied waves among various types of surface waves because they are easy to excite and have been used in many optical applications particularly for plasmonic communication, sensing, and harvesting solar energy. In all these applications, especially on-chip plasmonic communication, scattering can be an important issue to deal with. Therefore, this paper aimed to theoretically inspect the scattering pattern of SPP waves from a perfect electric conductor (PEC) cylindrical scatterer. The cylindrical wave approach is used to solve the scattering problem by a cylindrical object placed below a metallic layer. The scattering is investigated thoroughly by changing the size of the scatterer and its distance from the interface along which the SPP wave is excited. As the size of the scatterer increases, the scattering increases significantly. On the other hand, when the distance of the scatterer from the interface is increased, the scattered field becomes small. Two-dimensional field maps are produced for the incident angle at which SPP is excited. Numerical results are also presented for other incident angles to make a comparison. Furthermore, the forward and backward far-fields are significantly enhanced if the SPP wave is scattered in comparison with when the SPP wave is not present.

  相似文献   
67.
68.
Host plant nutritional quality can directly and indirectly affect the third trophic levels. The aphid–parasitoid relationship provides an ideal system to investigate tritrophic interactions (as the parasitoids are completely dependent for their development upon their hosts) and assess the bottom up forces operating at different concentrations of nitrogen applications. The effects of varying nitrogen fertilizer on the performance of Aphidius colemani (V.) reared on Sitobion avenae (F.) and Aphidius rhopalosiphi (D.) reared on Rhopalosiphum padi (L.) were measured. Parasitism and percent emergence of parasitoids were positively affected by nitrogen fertilizer treatments while developmental duration (egg, larval, and pupal stages) was not affected by increasing nitrogen inputs. In males and females of both parasitoid species, adult longevity increased with the increasing nitrogen fertilizer. Hind tibia length and mummy weight of both parasitoid species increased with nitrogen fertilizer concentrations, as a result of larger aphids. This study showed that nitrogen application to the soil can have important consequences for aboveground multitrophic interactions.  相似文献   
69.
Cancer is the second leading cause of deaths worldwide. Despite concerted efforts to improve the current therapies, the prognosis of cancer remains dismal. Highly selective or specific blocking of only one of the signaling pathways has been associated with limited or sporadic responses. Using targeted agents to inhibit multiple signaling pathways has emerged as a new paradigm for anticancer treatment. Icariside II, a flavonol glycoside, is one of the major components of Traditional Chinese Medicine Herba epimedii and possesses multiple biological and pharmacological properties including anti-inflammatory, anti-osteoporosis, anti-oxidant, anti-aging, and anticancer activities. Recently, the anticancer activity of Icariside II has been extensively investigated. Here, in this review, our aim is to give our perspective on the current status of Icariside II, and discuss its natural sources, anticancer activity, molecular targets and the mechanisms of action with specific emphasis on apoptosis pathways which may help the further design and conduct of preclinical and clinical trials.Icariside II has been found to induce apoptosis in various human cancer cell lines of different origin by targeting multiple signaling pathways including STAT3, PI3K/AKT, MAPK/ERK, COX-2/PGE2 and β-Catenin which are frequently deregulated in cancers, suggesting that this collective activity rather than just a single effect may play an important role in developing Icariside II into a potential lead compound for anticancer therapy. This review suggests that Icariside II provides a novel opportunity for treatment of cancers, but additional investigations and clinical trials are still required to fully understand the mechanism of therapeutic effects to further validate it in anti-tumor therapy.  相似文献   
70.
To date, six candidate genera of anaerobic ammonium‐oxidizing (anammox) bacteria have been identified, and numerous studies have been conducted to understand their ecophysiology. In this study, we examined the physiological characteristics of an anammox bacterium in the genus ‘Candidatus Jettenia’. Planctomycete KSU‐1 was found to be a mesophilic (20–42.5°C) and neutrophilic (pH 6.5–8.5) bacterium with a maximum growth rate of 0.0020 h?1. Planctomycete KSU‐1 cells showed typical physiological and structural features of anammox bacteria; i.e. 29N2 gas production by coupling of 15NH4+ and 14NO2?, accumulation of hydrazine with the consumption of hydroxylamine and the presence of anammoxosome. In addition, the cells were capable of respiratory ammonification with oxidation of acetate. Notably, the cells contained menaquinone‐7 as a dominant respiratory quinone. Proteomic analysis was performed to examine underlying core metabolisms, and high expressions of hydrazine synthase, hydrazine dehydrogenase, hydroxylamine dehydrogenase, nitrite/nitrate oxidoreductase and carbon monoxide dehydrogenase/acetyl‐CoA synthase were detected. These proteins require iron or copper as a metal cofactor, and both were dominant in planctomycete KSU‐1 cells. On the basis of these experimental results, we proposed the name ‘Ca. Jettenia caeni’ sp. nov. for the bacterial clade of the planctomycete KSU‐1.  相似文献   
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