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71.
利用主成分分析和非负最小二乘法,建立了我国近海常见的11种赤潮藻在属水平上的活体荧光识别测定技术.利用Delaunay三维插值法,消除浮游藻三维荧光光谱的瑞利散射和拉曼散射峰, 根据Fisher判别分析方法对各主成分及其组合的分辨能力的判别结果,确定赤潮藻三维荧光光谱的第一主成分得分谱和第二主成分得分谱作为赤潮藻识别特征谱,建立赤潮藻荧光特征谱库,在此基础上,利用非负最小二乘法对11种赤潮藻在属水平上进行识别测定,赤潮藻的识别正确率≥85%,其中9种赤潮藻的识别正确率≥90%,特别是对于近几年东海发生赤潮频率极高的东海原甲藻(Prorocentrum donghaiense)、中肋骨条藻(Skeletonema costatum)和裸甲藻(Gymnodinium sp.),识别正确率≥95%.本研究表明,利用主成分分析提取赤潮藻三维荧光光谱特征以实现赤潮藻在属水平上的识别测定是可行的.  相似文献   
72.
通过对 6个震例的分析研究 ,总结出电磁辐射源来自陆域空间和海域空间的规律 ;震前电磁异常的识别及非震异常的特征与排除 ,并成功地进行了一次临震预报。  相似文献   
73.
A novel multivariate method based on principal component analysis of pre-processed sections of chromatograms is used to characterize the complex PAH pollution patterns in sediments from Guanabara Bay, Brazil. Five distinct sources of 3- to 6-ring PAHs could be revealed. The harbour is the most contaminated site in the bay, its plume stretches in a South West to North East direction and the chemical profile indicates mainly pyrogenic sources mixed with a fraction of high-molecular-weight petrogenic PAHs. Rio São João de Meriti is the second largest source of PAHs, and introduces mainly a fraction of low-molecular-weight petrogenic PAHs from the western region of Rio de Janeiro. The sites close to the ruptured pipeline at the Duque de Caxias Refinery show a distinctive pollution pattern indicating a heavy petroleum fraction. The method also led to the identification of new potential indicator ratios also involving coeluting peaks (e.g., triphenylene and chrysene).  相似文献   
74.
桃园煤矿北八采区在开拓掘进过程中煤系砂岩多处出现涌水现象,且涌水量大、水温高、水质异常。为了判断北八采区砂岩水的水源,对矿井各含水层及北八采区砂岩水进行了系统采样,并对常规水化学指标进行了测试和分析。结果表明:北八采区煤系砂岩水与井田南部采区砂岩水水化学指标存在较大差异,而与奥灰水的水化学指标基本一致,该区"砂岩水"已不具有正常砂岩裂隙水的水质特征,具有奥灰水的水质特征,接受奥灰含水层水的补给。研究成果为该区"砂岩水"的防治提出了可靠的地质依据。  相似文献   
75.
Religious harassment claims in the United States have risen sharply over the past decade. However, victims of religious harassment may not always report harassment, and true rates may be higher. Hence, actions taken by third parties present (observers) are important in combating harassment in the workplace. The purpose of this paper is to extend a previous model of observer intervention and related research by testing it empirically in the context of religious harassment and identify factors that influence observers' decision to intervene (intervention), when they intervene (level of immediacy), and how much they intervene (level of involvement). Across two studies, we find evidence that verbal harassment, ambiguity of intent, relationship to target/harasser, recurrence belief, religious commitment, pro‐social orientation, and the interactive effect of shared religion and religious commitment predict intervention. Furthermore, individuals show higher levels of involvement and immediacy in intervention when costs are low and emotional reactions are high. Implications of these findings for engaging observers in combatting harassment are discussed. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
76.
The spatial distribution of an important air pollutant class, three-ring polycyclic aromatic hydrocarbons and their derivatives (PAH-3), has been monitored for the Greater Cologne Conurbation (GCC) using pine needle as passive samplers. The GCC comprises one of the most heavily populated, trafficked, and industrialized regions in Germany. Here, 71 locations covering 3600 km2 were sampled and, for the first time, isopleths maps constructed to investigate the regional variability in PAH-3 concentration and composition. The highest PAH-3 loads on needles (1000-1500 ng g−1) were detected downwind of three lignite fuelled power plants, followed by Cologne City (600-700 ng g−1) and smaller towns (400-600 ng g−1), whereas rural and forest regions yielded PAH-3 loads of 60-300 ng g−1. PAH-3 ratios facilitated source reconciliation, with high dibenzothiophene versus retene values indicating lignite combustion and high 9/(9 + 1)-methylphenanthrene ratios depicting traffic emissions in inner cities. PAH-3 ratios depended on topography and outlined the heavily industrialized Rhine Valley, demonstrating atmospheric dispersal of PAH-3.  相似文献   
77.
For potentially cannibalistic animals such as spiders, the ability to recognize and avoid kin and/or preferentially cannibalize non-relatives would permit exploiting conspecifics as prey while minimizing loss of inclusive fitness. We investigated the effects of relatedness and availability of alternative food on cannibalism tendency in pairs of juvenile Hogna helluo (Walckenaer), a North American wolf spider (Araneae: Lycosidae). For second-instar spiderlings (dispersing stage), cannibalism was more likely among pairs of non-sibs than pairs of sibs and, interestingly, was also more likely when other prey were available. We found no evidence of increased cannibalism in pairings involving broods of greatest average size disparity, indicating that size differences are unlikely to explain differences in cannibalism tendency. Additionally, the relative number of deaths from cannibalism or other causes did not increase with increasing risk of starvation. For third-instar spiderlings, which had lived independently of their mother and sibs following dispersal, cannibalism rates were very high in all treatments and there were no significant effects of relatedness or food availability. Our results suggest that spiders with predominantly solitary lifestyles may bias cannibalism toward non-kin during the juvenile associative period, and that this effect is lost in the subsequent instar. Results are discussed in the context of several potential mechanisms that might result in differential cannibalism.Communicated by M. Elgar  相似文献   
78.
Pollimyrus adspersus discriminates the individually variable waveforms of Electric Organ Discharges (EODs) of conspecifics of only 150–250 s duration. We examined: (1) the discrimination threshold for artificially generated EODs of similar waveform, (2) the mechanism of signal analysis (spectral vs temporal) present, by determining the discrimination between different waveforms of identical amplitude spectra, and (3) the threshold field intensity and reach of discrimination. The triphasic P. adspersus EOD waveform was artificially generated by superimposing two Gaussians, one wide, the second narrow, inverted, and of threefold amplitude. The natural variability among individual EOD waveforms was simulated by phase-shifting one Gaussian relative to the other. The symmetrical waveform where the peaks of the two Gaussians coincided was used as a reference (phase shift=0, rewarded stimulus S+). Results were: (1) in food-rewarded conditioning experiments, trained fish (N=7) detected a phase-shift in artificial EOD stimuli as low as 2 s (N=2 fish), 6 s (N=1) and 10 s (N=1). (2) All fish tested (N=3) discriminated between artificial EODs of identical amplitude spectra but different waveforms (hence, different phase spectra), demonstrating a temporal mechanism of signal analysis. (3) The maximum reach of waveform discrimination was 130 cm at 4.9 Vp-p/cm and 100 S/cm water conductivity (test signal generated at natural amplitude), that is, similar to the reach of EOD detection. Therefore, among the three kinds of electroreceptor organ present in mormyrids, we consider Knollenorgane the relevant sensory organs for EOD waveform discrimination.Communicated by J. Krause  相似文献   
79.
Summary. Breeding burrows of Parastizopus armaticeps armaticeps, a fossorial desert tenebrionid beetle, are cleptoparasitised by the closely related Eremostibes opacus. Gas chromatographic analyses show a high congruity of the cuticular hydrocarbons of both species. We compare these hydrocarbon patterns with those of four other Stizopina species and the Scaurini Herpiscius sommeri. In a bioassay, dummies treated with cuticular hydrocarbon extracts of E. opacus and the P. a. bifidus parasite E. bushmanicus were mostly ignored by P. a. armaticeps, whereas dummies with applied extracts of the remaining species were heavily attacked. We show that there is a correlation between agonistic behaviour of P. a. armaticeps towards the intruder and the chemical similarity of the cuticular hydrocarbons of the two species. Furthermore, we produced quantitatively modified hydrocarbon patterns of E. barbatus by changing the temperature at which this species was kept. The new 30 °C type was chemically similar to E. opacus, and was frequently ignored by P. a. armaticeps, whereas a reduction of the temperature to 20 °C only had minor effects on the hydrocarbon pattern. Furthermore, we show that the addition of one single component, heptacosane, to the cuticular hydrocarbon extract of E. opacus alters the host’s reaction. We discuss the role of cuticular hydrocarbons for the recognition of this host-parasite system and the relevance of quantitative characters in the hydrocarbon pattern for the discrimination of the host.  相似文献   
80.
Habituation and its role in the dear enemy effect was investigated in a population of green frogs, Rana clamitans. Green frogs have a prolonged breeding season, and males defend territories centered around suitable oviposition sites. We tested the prediction that male green frogs will habituate to broadcasts of synthetic conspecific stimuli. Our results indicate that male green frogs can discriminate familiar from unfamiliar stimuli. We suggest that habituation helps to mediate the territorial interactions between male green frogs. Strangers present a greater threat than familiar neighbors. By habituating to the advertisement vocalizations of their near neighbors, males avoid costly interactions with individuals that are not a major threat to their territories. Received: 20 July 1998 / Accepted after revision: 6 September 1998  相似文献   
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