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1.
Heat-shock protein 70 expression in shrimp Fenneropenaeus chinensis during thermal and immune-challenged stress 总被引:4,自引:0,他引:4
Using western immunoblotting, we obtained heat-shock protein 70 (HSP70) induction data and distribution in different tissues from shrimp Fenneropenaeus chinensis during thermal and immune-challenged stresses. This is probably the first report of the effects of various stressors on the expression of HSP70 in shrimp.HSP70 was prominently induced in hepatopancreas and gills, but not in muscle, eyestalk and hemolymph, when the shrimp were exposed to heat shock and Vibrio anguillavium-challenged stresses. Cold shock and WSSV treatment had no significant effects on the levels of HSP70 expression in all tissues examined. HSP70 induction was greatest after 2 h exposure to heat shock stress, which was elevated after acute heat shock exposure of 10℃ above ambient temperature. 相似文献
2.
Y.-B. WU S. GAO H.-J. GONG H. XIANG W.-F. JIAO S.-H. YANG Y.-S. LIU H.-L. YUAN 《Journal of Metamorphic Geology》2009,27(6):461-477
U–Pb age, trace element and Hf isotope compositions of zircon were analysed for a metasedimentary rock and two amphibolites from the Kongling terrane in the northern part of the Yangtze Craton. The zircon shows distinct morphological and chemical characteristics. Most zircon in an amphibolite shows oscillatory zoning, high Th/U and 176 Lu/177 Hf ratios, high formation temperature, high trace element contents, clear negative Eu anomaly, as well as HREE-enriched patterns, suggesting that it is igneous. The zircon yields a weighted mean 207 Pb/206 Pb age of 2857 ± 8 Ma, representing the age of the magmatic protolith. The zircon in the other two samples is metamorphic. It has low Th/U ratios, low trace element concentrations, variable HREE contents (33.8 ≥ LuN ≥2213; 14.7 ≤ LuN /SmN ≤ 354) and 176 Lu/177 Hf ratios (0.000030–0.001168). The data indicate that the zircon formed in the presence of garnet and under upper amphibolite facies conditions. The metamorphic zircon yields a weighted mean 207 Pb/206 Pb age of 2010 ± 13 Ma. These results combined with previously obtained Palaeoproterozoic metamorphic ages suggest a c. 2.0 Ga Palaeoproterozoic collisional event in the Yangtze Craton, which may result from the assembly of the supercontinent Columbia. The zircon in two samples yields weighted mean two-stage Hf model ( T DM2 ) ages of 3217 ± 110 and 2943 ± 50 Ma, respectively, indicating that their protoliths were mainly derived from Archean crust. 相似文献
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5.
Yuan-Bao Wu Shan Gao Hong-Fei Zhang Sai-Hong Yang Wen-Fang Jiao Yong-Sheng Liu Hong-Lin Yuan 《Contributions to Mineralogy and Petrology》2008,155(1):123-133
The Hong’an area (western Dabie Mountains) is the westernmost terrane in the Qinling-Dabie-Sulu orogen that preserves UHP
eclogites. The ages of the UHP metamorphism have not been well constrained, and thus hinder our understanding of the tectonic
evolution of this area. LA-ICPMS U–Pb age, trace element and Hf isotope compositions of zircons of a granitic gneiss and an
eclogite from the Xinxian UHP unit in the Hong’an area were analyzed to constrain the age of the UHP metamorphism. Most zircons
are unzoned or show sector zoning. They have low trace element concentrations, without significant negative Eu anomalies.
These metamorphic zircons can be further subdivided into two groups according to their U–Pb ages, and trace element and Lu–Hf
isotope compositions. One group with an average age of 239 ± 2 Ma show relatively high and variable HREE contents (527 ≥ LuN ≥ 14) and 176Lu/177Hf ratios (0.00008–0.000931), indicating their growth prior to a great deal of garnet growth in the late stage of continental
subduction. The other group yields an average age of 227 ± 2 Ma, and shows consistent low HREE contents and 176Lu/177Hf ratios, suggesting their growth with concurrent garnet crystallization and/or recrystallization. These two groups of age
are taken as recording the time of prograde HP to UHP and retrograde UHP–HP stages, respectively. A few cores have high Th/U
ratios, high trace element contents, and a clear negative Eu anomaly. These features support a magmatic origin of these zircon
cores. The upper intercept ages of 771 ± 86 and 752 ± 70 Ma for the granitic gneiss and eclogite, respectively, indicate that
their protoliths probably formed as a bimodal suite in rifting zones in the northern margin of the Yangtze Block. Young Hf
model ages (T
DM1) of magmatic cores indicate juvenile (mantle-derived) materials were involved in their protolith formation.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
6.
土壤渗滤处理系统设备简单、投资少、操作管理方便、能耗低,净化效果良好,在处理海岛生活污水领域具有广阔的发展前景.根据鼓浪屿目前污水水质、水量的特点,采用土壤渗滤高度水处理技术对污水进行处理,污染物经过土壤的物理、化学和生物作用,出水达到《城市污水再生利用城市杂用水水质》(GB/T18920-2002),具有不产生污泥,运行简单,氮磷去除效率高,无二次污染等特点. 相似文献
7.
本文提出了~(15)N示踪-离子质谱法实测新生产力的方法,并于1991年11月—1992年5月结合胶州湾现场调查的实际样品,对示踪剂量、培养时间、样品贮存、消解剂量和时间、铵离子的扩散吸收,以及方法的空白值、检出限、精密度和准确度等进行了实验研究。结果表明,该法具有较高的精密度和良好的准确度,与经典的气体质谱法相比,还具有进样量少以及可同时分析~(15)N丰度、总氮浓度和水中铵离子浓度等特点,对于含氮量极低、铵氮再生迅速的海洋环境中新生产力的研究,具有特殊的意义。 相似文献
8.
本文提出了一种地震折射液的虚拟射线理论,根据该理论,只要已知地表层的速度,即可直接由折射波信息提取地震参数,从而可实现折射界面的反演。 文中通过实际介质模型的计算机实验结果,验证了该理论的正确性。 相似文献
9.
Environmental control of growth and BChl a expression in an aerobic anoxygenic phototrophic bacterium, Erythrobacter longus (DSMZ6997) 总被引:1,自引:0,他引:1
1Introduction Aerobic anoxygenic phototrophic bacteria(AAPB) are facultative heterotrophs that can utilizelight for photosynthesis. These unique-functioningbacteria are widely distributed in marine environ-ments, such as coastal waters (Shiba et al., 1991… 相似文献
10.
1 .IntroductionNondestructiveinspection (NDI)isveryimportantforensuringthereliabilityofoffshorestructuresintheirservicelives (Lauraetal.,1 996 ) .Itiswellknownthatdetectionofflawsinvolvesconsider ablestatisticaluncertainties.Asaresult,theprobabilityofdetection (POD)forallflawsofagivensizehasbeenusedintheliteraturetodefinethecapabilityofaparticularNDItechniqueinagivenen vironment.SincethedataofPODusuallyscatterlargely ,itisdifficulttodeterminewhichmodelfitstheavailabledatabest.Thismodelun… 相似文献