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The Photochemical Reflectance Index (PRI) has been proposed as a tool for the estimation of leaf and canopy light-use efficiency and photosynthesis from remote-sensing data. The application of the index is based on more than fifteen years of spectroscopic studies at the leaf level, which support it with a sound physiological basis. In the present study, the correlation between PRI and instantaneous light-use efficiency was estimated across a range of vegetation types in the San Rossore Regional Park, a CHRIS-Proba core site. The relationship was also tested over an entire season for a pine forest in the Park where carbon fluxes have been monitored by eddy-covariance over the last five years. Seasonal changes in photosynthetic potential were also monitored at the site, in order to test the correlation with PRI reported in the literature. In September 2004, estimates of canopy PRI from CHRIS images were compared with leaf-level measurements from 13 plots corresponding to different vegetation types. The results were used to extrapolate leaf-level information to the entire scene.

Batesian and aggressive mimics are considered to be under selective pressure to resemble their models, whereas signal receivers are under selection to discriminate between mimics and models. However, the perceptual ability of signal receivers to discriminate between mimics and models is rarely studied. Here we examined 15 model–mimic coral reef fish pairs using nonsubjective methods to judge the accuracy of mimics in terms of color and luminance. We then investigated the potential ability of fish with various visual systems to discriminate between model and mimic colors using theoretical vision models. We found the majority of mimics closely resembled models in terms of color and luminance from a nonsubjective perspective. However, fish that have potentially trichromatic (3 distinct cone photoreceptors) visual systems with ultraviolet sensitivity had a much better capacity to discriminate between models and mimics compared with fish with midrange sensitivity or dichromatic (2 cone photoreceptors) fish. The spectral reflectance of color patches reflected by models and mimics became more similar with an increase in depth, indicating that signal receivers may be more likely to distinguish mimics from models in habitats located closer to the surface. There was no such change in luminance contrast with depth. The selection pressure on mimics to accurately resemble their model is therefore predicted to vary depending on the visual system of the signal receiver and the light environment. Key words: aggressive mimicry, animal signaling, Batesian, color vision, signal accuracy. [Behav Ecol 20:459–468 (2009)]

Pronounced altitudinal and latitudinal UV-B gradients exist across the earth. Therefore, we hypothesised that plants from different geographic origins differ in the regulation and/or magnitude of UV-protection. Eight Arabidopsis accessions with different geographic origins (altitude between 32 and 3016 m) were raised under Photosynthetic Active Radiation (PAR), PAR + UV-A or PAR + UV-A + UV-B radiation for 10 days, after which UV-B protection of photosynthesis was assessed by measuring the consequences of exposure to a pulse of acute UV-B. We found significant variation in UV-B protection among accessions exposed to PAR or PAR + UV-A. Yet, all accessions raised under PAR + UV-A + UV-B were well protected. Thus, differences between accessions are not about UV-B protection per sé, but rather about regulation of UV-B protection which varies from constitutive to inducible by UV-A and/or UV-B. Particularly striking are differential UV-A responses, whereby some high altitude accessions lack UV-A regulated accumulation of UV-absorbing pigments, but show a strong UV-A induced morphogenic response. The adaptive relevance of the differential regulation of UVprotection is discussed.

光致荧光技术及荧光光谱成像技术以其实时、微创或无创、副作用小及灵敏度高等特点,在肿瘤疾病的诊断上够得到了广泛地应用。癌症也称恶性肿瘤,是指机体在各种致瘤因素作用下,局部组织细胞异常增生而形成的局部肿块。恶性肿瘤可以破坏组织、器官的结构和功能,患者最终可能由于器官功能衰竭而死亡。因此对恶性肿瘤的早期诊断就显得尤为重要。

用标准的珠宝鉴定紫外灯(波长为365 nm 和254 nm)对天然蓝色和无色以及辐照处理蓝色托帕石样品进行测试发现,天然蓝色托帕石的紫外荧光强度从强到弱,变化较大, 而各种辐照处理蓝色托帕石的紫外荧光强度均微弱甚至不显现?在紫外荧光测试的基础上, 使用BY-1 阴极发光仪和美国Ocean Optics 的USB2000 型CCD 多通道光谱仪对其阴极发光特征进行了重点研究?结果表明,天然蓝色托帕石的阴极发光强度最强,天然无色托帕石的次之, 辐照处理蓝色托帕石的最弱, 仅为天然蓝色托帕石的1 /3。因此, 阴极发光测试可以快速?无损鉴别天然和辐照处理蓝色托帕石。

动脉血气分析是监测气体交换和代谢的重要手段,尤其是呼吸衰竭等危重病人及手术麻醉期间。但是传统的血气分析须要间断采集血样,送实验室用血气分析仪分析,检验报告滞后,对于需要长期监测血气的危重病人,则需要反复多次抽血,极为不便,且易发生医源性感染。

颜色是评定翡翠价值的主要因素?利用色度学原理,使用USB2000 仪器通过对绿色翡翠反射曲线和色度学参数的测定,采用国际照明委员会CIE1931—XYZ 色度坐标和颜色指数分析方法来定量描述绿色翡翠的颜色,将目测样品颜色与仪器检测的数据进行比较,实验结果比较相符,表明色度学的测量方法在表征绿色翡翠的颜色方面较为准确,且不同品种的绿色翡翠样品的颜色呈规律分布?

尝试利用漫反射光谱检测鲜红斑痣皮肤的氧含量, 并用于监测光动力治疗中鲜红斑痣皮肤氧含量的变化?采用Ocean Optics 公司生产的USB2000 微型光纤光谱仪采集PWS 皮肤的漫反射光谱, 根据氧合血红蛋白与还原血红蛋白(皮肤中两种主要的吸光基团)吸收光谱的差异, 分析病变皮肤氧含量及治疗中氧含量的变化趋势。对14 例PWS 患者进行治疗中皮肤漫反射光谱的监测。结果显示, 治疗前不同类型PWS 皮肤氧含量不同, 光动力治疗中大部分P4、P5 型PWS 皮肤氧含量没有显著降低, P6 型PWS 皮肤氧含量降低明显,表明现有的漫反射光谱法可定性监测PWS 皮肤氧含量的变化趋势?通过进一步提高仪器的灵敏度并建立相应的光谱分析方法, 有望更准确地测量PWS 皮肤中的氧含量变化。

使用等离子体增强化学气相沉积(PE-CVD)的方法, 以TTIP (Ti(OC3H7)4)为单体, 用氧气为载气, 以脉冲偏压为辅助在室温的玻璃基片上沉积无定型TiO2 薄膜, 分析探讨在射频等离子体增强化学气相沉积TiO2 薄膜的过程中, 基片上施加脉冲偏压和远离脉冲偏压的情况下成膜的比较.在沉积的过程中, 利用USB-2000 型光纤光谱仪对等离子体的发射光谱进行测量, 定性分析等离子体沉积过程中的成分组成.用UV-1901 探讨薄膜的光学特性, 发现紫外和近紫外区域有一定吸收;用扫描电镜分析薄膜表面形貌的变化, 可以看到偏压下的薄膜致密无孔, 而远离偏压下的薄膜形貌粗糙;用红外光谱分析薄膜的结构组成,可以看到明显的Ti—O 吸收峰.脉冲偏压下得到的薄膜在化学、光学以及电学方面有很好应用前景.

软玉的颜色品种多样,其中翠青玉作为青海三岔河的一个特殊颜色品种受到市场上的追捧。为了研究翠青玉的主要成分及颜色成因,选取多个具有渐变色的代表性样品,分别对其运用红外光谱仪、拉曼光谱仪、激光剥蚀电感耦合等离子体质谱仪(ICP-MS)、USB2000光纤光谱仪进行了测试,通过红外?拉曼光谱发现翠青玉由透闪石组成,ICP-MS的成分测试结果显示该样品的翠绿色与Cr3+ 离子的质量分数呈正比,USB2000光纤光谱仪显示翠青玉中翠绿色部分的主波长在557nm附近,并且吸收光谱表现为橙黄区与蓝紫区的吸收,通过一系列的实验数据对翠青玉中致色离子的占位情况进行了相关讨论,并分析该离子来源于成矿母体中的基性岩浆岩。

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