910 resultados para lily bulb


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百合是重要的球根花卉,是世界五大切花之一。我国的百合野生资源丰富,但百合鲜切花生产与世界花卉大国相比仍然存在差距,优质的商品种球大量依靠进口,实现商品种球国产化能够促进百合鲜切花生产和农业经济发展。温度是影响百合生长发育最重要的因子之一,影响百合鳞茎发育,限制百合的分布区域。 百合鳞茎具有自然休眠的特性,低温处理是目前打破百合鳞茎休眠的最常用的方法。低温处理期间,鳞茎内发生复杂的反应,淀粉水解,鳞茎内的淀粉酶(α-淀粉酶和β-淀粉酶)活性增加,可溶性糖主要是蔗糖积累;可溶性蛋白质含量增加,游离氨基酸在鳞茎相对幼嫩的器官中集中;休眠解除期间脱落酸和玉米素核苷含量呈下降趋势,赤霉素含量呈上升趋势且活性增高,鳞茎各部位生长素都有上升,一些其他生长调节剂如Me-JA和多胺对解除百合鳞茎也有作用。低温处理期间,鳞茎内各种激素相互作用,共同调控鳞茎的休眠状态。利用低温处理打破百合鳞茎休眠的过程中,温度要求控制在稳定的范围内。利用冰箱低温处理打破百合鳞茎休眠的实验中,放入样品前冰箱内的温度在所设定温度±1℃范围内波动,且不同部位温度均匀;但冰箱内放入样品后,其内部不同部位的温度相差较大,表现为上部温度高,下部温度低,冰箱内部不同部位温度差异很大。 从百合资源在中国的分布看,华北地区的百合资源相对稀缺,温度是限制其生长的重要环境因子。新铁炮百合能够在炎热的华南地区露地栽培,将其在华北地区进行区域化露地栽培实验,对百合栽培应用推广,扩大栽培面积,降低运输成本,以及保证鲜切花质量有重要意义。通过气体交换测定的光合作用是对高温最敏感和综合的生理指标,可以在植物生长和生物量积累未发生明显变化之前揭示高温的影响。本研究通过人工气候箱,设定四个温度梯度:25℃,32℃,38℃,44℃,处理2h,通过测定新铁炮百合幼苗的光合特性研究其耐热程度、探讨可能的耐热机制。结果表明:净光合作用速率(Pn)在小于38℃时下降幅度不大,大于38℃后显著下降,随着处理温度的提高,气孔导度(Gs)呈下降的趋势,胞间二氧化碳浓度(Ci)则上升,而气孔限制值(Ls)下降。高温下,两品种叶片最小荧光(Fo)无明显变化,最大荧光(Fm)和光系统II(PSⅡ)最大光化学效率(Fv/Fm)下降程度较小;光下,PSⅡ实际光化学效率(ΦPSⅡ)呈下降趋势,44℃处理后显著下降;NPQ随处理温度的提高而上升;处理温度升高,SOD、APX、CAT、POD活力增强。研究表明新铁炮百合能够耐受32-38℃的高温;热胁迫下,叶片通过提高非光化猝灭和抗氧化酶活性两种机制来抵御高温胁迫。

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Gilding the Lily, a Gold Coast version of Ephraim, the biblical 'great kingdom to the north', is a $545 million development that will have 385 residences when it is finished in 2007. EDAW Australia's Brisbane office was responsible for the reclaimed island's landscape architecture.

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The close relationship between rain and lightning is well known. However, there are numerous documented observations of heavy rain accompanied by little or no lightning activity (Williams et al, 1992; Jayaratne, 1993). Kuleshov et al (2002) studied thunderstorm distribution and frequency in Australia and concluded that thunderstorm frequency (as expressed by number of thunder-days) in Australia does not, in general, appear to vary in any consistent way with rainfall. However, thunder-days describe occurrence of thunderstorms as heard by an observer, and therefore could be only proxy data to evaluate actual lightning activity (i.e. number of total or cloud-to-ground flashes). Field experiments have demonstrated a strong increase in lightning activity with convective available potential energy (CAPE). It has also been shown that CAPE increases linearly with potential wet bulb temperature, Tw (Williams et al, 1992). In this study, we examine the relationship between lightning ground flash incidence and the two parameters – surface rainfall and surface wet bulb maximum temperature for selected localities around Australia...

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The Glashaus is considered a significant exemplar of early modernist architecture and is generally accepted as having had Expressionist origins. However, current research has revealed that the design origins of this important building are not fully understood. While the historical record acknowledges the contributions of the bohemian poet Paul Scheerbart and the art critic Adolf Behne, the role of the Glashaus’ architect, Bruno Taut, has been moderated. In an attempt to rectify this situation this article proposes that the design origins of the Glashaus can be found in a strong architect-client interaction. It is argued that the Glashaus’ client, the Deutsche Luxfer Prismen Syndikat under the directorship of Frederick Keppler, exerted a significant influence on its design. In order to showcase the glazed products of Luxfer in the best manner possible, Keppler insisted that the design feature a glazed dome, electric lighting, a fountain as well as a cascade. Given the detailed stipulations of this brief, Taut had few options other than to offer interpretations of precedent that derived from the Victoria regia lily and Gothic proportioning. By expounding this architect-client relationship, this article expands our understanding of the Glashaus, and reinvigorates our understanding of this important early example of modern architecture.

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Bruno Taut's Glashaus is considered a seminal example of early modernist architecture. Yet, some of the crucial factors behind the design of the Glashaus remain little understood. This PhD reveals that the Glashaus' patron, Frederick Keppler, exerted a significant influence over its design by insisting that it follow a prescriptive brief. Interpreting these rigid instructions, Taut as the architect, gained inspiration from the myths and symbols associated with the Victoria regia lily and the Gothic. This PhD therefore significantly expands the understanding of the Glashaus, and thus reinvigorates our comprehension of one of the most distinctive early examples of modern architecture.

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Axon targeting during the development of the olfactory system is not always accurate, and numerous axons overextend past the target layer into the deeper layers of the olfactory bulb. To date, the fate of the mis-targeted axons has not been determined. We hypothesized that following overextension, the axons degenerate, and cells within the deeper layers of the olfactory bulb phagocytose the axonal debris. We utilized a line of transgenic mice that expresses ZsGreen fluorescent protein in primary olfactory axons. We found that overextending axons closely followed the filaments of radial glia present in the olfactory bulb during embryonic development. Following overextension into deeper layers of the olfactory bulb, axons degenerated and radial glia responded by phagocytosing the resulting debris. We used in vitro analysis to confirm that the radial glia had phagocytosed debris from olfactory axons. We also investigated whether the fate of overextending axons was altered when the development of the olfactory bulb was perturbed. In mice that lacked Sox10, a transcription factor essential for normal olfactory bulb development, we observed a disruption to the morphology and positioning of radial glia and an accumulation of olfactory axon debris within the bulb. Our results demonstrate that during early development of the olfactory system, radial glia play an important role in removing overextended axons from the deeper layers of the olfactory bulb.

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The olfactory bulb of mammals aids in the discrimination of odors. A mathematical model based on the bulbar anatomy and electrophysiology is described. Simulations of the highly non-linear model produce a 35-60 Hz modulated activity, which is coherent across the bulb. The decision states (for the odor information) in this system can be thought of as stable cycles, rather than as point stable states typical of simpler neuro-computing models. Analysis shows that a group of coupled non-linear oscillators are responsible for the oscillatory activities. The output oscillation pattern of the bulb is determined by the odor input. The model provides a framework in which to understand the transformation between odor input and bulbar output to the olfactory cortex. This model can also be extended to other brain areas such as the hippocampus, thalamus, and neocortex, which show oscillatory neural activities. There is significant correspondence between the model behavior and observed electrophysiology.

It has also been suggested that the olfactory bulb, the first processing center after the sensory cells in the olfactory pathway, plays a role in olfactory adaptation, odor sensitivity enhancement by motivation, and other olfactory psychophysical phenomena. The input from the higher olfactory centers to the inhibitory cells in the bulb are shown to be able to modulate the response, and thus the sensitivity, of the bulb to odor input. It follows that the bulb can decrease its sensitivity to a pre-existing and detected odor (adaptation) while remaining sensitive to new odors, or can increase its sensitivity to discover interesting new odors. Other olfactory psychophysical phenomena such as cross-adaptation are also discussed.

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A LIBS setup was built in the Institute of Modern Physics. In our experiments, LIBS spectra produced by infrared radiation of Nd : YAG nanosecond laser with 100 and 150 mJ pulse energy, respectively, were measured by fiber optic spectrometer in the ranges of 230-430 run and 430-1080 nm with a delay time of 1.7 and gate width of 2 ms for potato and lily samples prepared by vacuum freeze-dried technique. The lines from different metal elements such as K, Ca, Na, Mg, Fe, Al, Mn and Ti, and nonmetal elements such as C, N, O and H, and some molecular spectra from C-2, CaO, and CN were identified according to their wavelengths. The relative content of the six microelements, Ca, Na, K, Fe, Al, and Mg in the samples were analyzed according to their representative line intensities. By comparison we found that there are higher relative content of Ca and Na in lily samples and higher relative content of Mg in potato samples. The experimental results showed that LIBS technique is a fast and effective means for measuring and comparing the contents of microelements in plant samples.

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The Heck arylation of 2-methylprop-2-en- I -ol in ionic liquids and organic solvents is reported using a range of homogeneous and heterogeneous palladium catalysts. Higher activity is observed in the ionic liquid media compared with N-methyl pyrrolidinone and under solventless conditions. The ionic liquid-catalyst system may be recycled easily with little loss in activity, although significant palladium leaching from the heterogeneous catalyst was observed. In the case of Trans-bis(2,3-dihydro-3-methylbenzothiazole-2-ylidene)diiodopalladium (11) reported to be highly active for this transformation, significant induction petiods were observed indicating that nanoparticles may be responsible for the catalysis. Using the ionic liquid Heck reaction, a recyclable synthesis for the fragrance beta-Lilial((R)) has been developed. (c) 2004 Elsevier B.V. All rights reserved.

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Despite the potential energy savings and economic benefits associated with compact fluorescent light bulbs, their adoption by the residential sector has been limited to date. In this paper, we present a theoretical model that focuses on the agents' ability to perceive the correct cost of lighting and on the role of environmental attitudes as key determinants of the adoption decision. We use original data from Ireland to test our theoretical predictions. Our results emphasize the importance of education, information and environmental awareness in the adoption decision.