The role of cytochrome P4501A activity inhibition in three- to five-ringed polycyclic aromatic hydrocarbons embryotoxicity of marine medaka (Oryzias melastigma)     

Mu JL  Wang XH  Jin F  Wang JY  Hong HS 《Marine pollution bulletin》2012,64(7):1445-1451

The mode of action of PAHs that causes fish developmental malformations is unclear. The embryotoxicity of marine medaka (Oryzias melastigma) was investigated after individual exposure to three- to five-ring PAHs Phe, Py, and BaP or co-exposure with α-ANF for 18 days. We found that the relationships between EROD induction and developmental deformities of embryos showed a various pattern under different exposure scenarios of Phe, Py, and BaP, which suggested possibly different modes of action in determining the developmental toxicities. As for co-exposure scenarios of each PAH combined with ANF, it showed potentially synergistic effects. The inhibited CYP1A mediated enzyme activity by ANF after co-exposure did not effectively alleviate developmental toxicity of embryo. It showed potentially synergistic effects after co-exposure of marine fish embryos to CYP1A inhibitors and PAH-type CYP1A inducers. Heart deformities in the early life stages of marine medaka were recommended as a biomarker for indicating the extent of PAH pollution.  相似文献   

Hydrological thresholds of soil surface properties identified using conditional inference tree analysis     

Matthew Tighe  Carlos Muñoz‐Robles  Nick Reid  Brian Wilson  Sue V. Briggs 《地球表面变化过程与地形》2012,37(6):620-632

There has been limited success in determining critical thresholds of ground cover or soil characteristics that relate to significant changes in runoff or sediment production at the microscale (<1 m²), particularly in semi‐arid systems where management of ground cover is critical. Despite this lack of quantified thresholds, there is an increasing research focus on the two‐phase mosaic of vegetation patches and inter‐patches in semi‐arid systems. In order to quantify ground cover and soil related thresholds for runoff and sediment production, we used a data mining technique known as conditional inference tree analysis to determine statistically significant values of a range of measured variables that predicted average runoff, peak runoff, sediment concentration and sediment production at the microscale. On Chromic Luvisols across a range of vegetation states in semi‐arid south‐eastern Australia, large changes in runoff and sediment production were related to a hierarchy of different variables and thresholds, but the percentage of bare soil played a primary role in predicting runoff and sediment production in most instances. The identified thresholds match well with previous thresholds found in semi‐arid and temperate regions (including the approximate values of 30%, 50% and 70% total ground cover). The analysis presented here identified the critical role of soil surface roughness, particularly where total ground cover is sparse. The analysis also provided evidence that a two‐phase mosaic of patches and inter‐patches identified via rapid visual assessment could be further delineated into distinct groups of hydrological response, or a multi‐phase rather than a two‐phase system. The approach used here may aid in assessing scale‐dependent responses and address data non‐linearity in studies of semi‐arid hydrology. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

AHS and CASI Processing for the REFLEX Remote Sensing Campaign: Methods and Results     

Eduardo de Miguel  Marcos Jiménez  Irene Pérez  Óscar G. de la Cámara  Félix Muñoz  José A. Gómez-Sánchez 《Acta Geophysica》2015,63(6):1485-1498

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Computer Simulation of Packing of Particles with Size Distributions Produced by Fragmentation Processes     

Miguel Angel Martín  Francisco J. Muñoz  Miguel Reyes  F. Javier Taguas 《Pure and Applied Geophysics》2015,172(1):141-148

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基于高光谱影像数据的戈壁表面砾石粒径定量反演潜力评估     

曹晓阳  穆悦  曹晓明  冯益明 《中国沙漠》2015,35(4):850-856

在新疆哈密境内的噶顺戈壁选取样地,采集不同粒径砾石的光谱数据,分析光谱吸收特征,并利用光谱混合分析技术,以地物光谱为端元从EO-1 Hyperion 高光谱影像中提取了不同粒径的丰度图,分析戈壁表面砾石与高光谱影像的相关关系。结果表明:获取的地物光谱特征显示出粒径的差异对光谱具有明显的影响。所有光谱都展现出在2 250 nm处具有Al–OH 的吸收特性,而且粒径d=41 cm的吸收特性比其他粒径都更显著。而与更小粒径相比,粒径d=53 cm和d=83 cm在480 nm和920 nm处具有较弱的Fe³⁺ 吸收特性。粒径d=0.8 cm(R²=0.637)、d=3.4 cm(R²=0.687)、d=16.3 cm(R² =0.644)及d=41 cm(R²=0.622) 与相应的丰度影像具有显著相关性,而粒径d=53 cm(R²=0.181)和d=83 cm(R²=0.167)与相应的丰度影像相关性不显著。EO-1高光谱影像适用于对戈壁区砾石分布特征的确定,在进一步的研究中将高分辨率影像与高光谱影像相结合,可以提高判别精度。  相似文献   

Relatively short-term correlation among deformation,degassing, and seismicity: a case study from Concepción volcano,Nicaragua   总被引：1，自引：0，他引：1  

José Armando Saballos  Vladimir Conde  Rocco Malservisi  Charles B. Connor  Julio Álvarez  Angélica Muñoz 《Bulletin of Volcanology》2014,76(8):1-11

Concepción is a frequently active composite volcano in Nicaragua, and is located on Ometepe Island, within Lake Nicaragua. Significant eruptive activity took place at this volcano between March and May 2010, consisting of ash and gas explosions (VEI 1–2). We compare geodetic baseline changes observed with global positioning system (GPS), sulfur dioxide flux (SO₂), and seismic amplitude (SAM) data collected at Concepción during April – June, 2010, and February – April, 2011. Time series analysis reveals a remarkable correlation among the data sets during 2010, when the volcano was erupting. In contrast, the volcano was at its background level of activity in 2011 and the statistical correlation among the time series is not significant for this period. We explain the emergence of correlation among the time series during eruptive activity through modeling of the GPS data with emplacement of a magma column in an open conduit. In the model, magma rose in the conduit, between May 5 and 14, 2010, from a shallow reservoir located at ～ 1.8 km depth. Later, between May 24 and 31, 2010, the top of the magma column descended to almost 600 m depth, corresponding to the cessation of eruptive activity. Thus, cross-correlation and an integrated analysis of these geophysical time series on a timescale of days helps to reveal the dynamics of the magma plumbing system operating below Concepción volcano.  相似文献   

Quantification of Ionic Liquids Concentration in Water and Qualification of Conjugated and Inductive Effects of Ionic Liquids by UV Spectroscopy          下载免费PDF全文

Yuanyuan Cao  Yu Chen  Xiaofu Sun  Tiancheng Mu 《洁净——土壤、空气、水》2014,42(8):1162-1169

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城市扩张对东莞市陆表温度的影响分析   总被引：2，自引：0，他引：2  

冯徽徽  刘慧平  朱寿东  白穆 《地理与地理信息科学》2010,26(3)

利用1995年12月30日、2003年1月10日两期Landsat TM/ETM遥感影像反演东莞市陆表温度(LST),分析东莞市陆表温度的总体情况及时空特征,并通过引入温度植被指数(Temperature-Vegetation Index,TVX)空间方法,研究城市化对陆表温度的影响.结果表明:城市化进程是导致东莞市陆表温度上升的重要原因,这种作用在TVX空间中主要体现在聚类点由高植被覆盖-低温度向低植被覆盖-高温度区域的运动过程.  相似文献   

Time-Based Network Analysis Before and After the M_w  8.3 Illapel Earthquake 2015 Chile     

Denisse Pastén  Felipe Torres  Benjamín Toledo  Víctor Muñoz  José Rogan  Juan Alejandro Valdivia 《Pure and Applied Geophysics》2016,173(7):2267-2275

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静乐井SWY-Ⅱ和LN-3A水位仪的对比分析     

胡玉良  程冬焱  李惠玲  穆慧敏  郭宇  刘俊芳 《中国地震》2016,32(1):93-102

对静乐井SWY-Ⅱ水位仪和LN-3A水位仪从稳定性、数据一致性、内在质量、系统漂移、水震波、气压效应、自然环境干扰7方面进行了对比分析,结果显示:①SWY-Ⅱ水位仪和LN-3A水位仪运行稳定;②两套仪器观测数据一致性较好;③两套仪器测量精度均优于0.001m,平均值一致性较好。④通过计算分钟值数据,两套仪器M2波潮汐因子及其观测精度较为接近;⑤通过与SW40-1水位仪进行对比,两套仪器均存在不同程度系统漂移;⑥两套仪器分钟值数据记录水震波时间及振幅差异明显;⑦两套仪器的气压效应、受自然环境干扰影响较为一致。  相似文献