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Application of 3D GPR attribute technology in archaeological investigations 被引量:5
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作者 赵文轲 田钢 +3 位作者 王帮兵 石战结 林金鑫 《Applied Geophysics》 SCIE CSCD 2012年第3期261-269,359,360,共11页
Ground penetrating radar (GPR) attribute technology has been applied to many aspects in recent years but there are very few examples in the field of archaeology. Especially how can we extract effective attributes fr... Ground penetrating radar (GPR) attribute technology has been applied to many aspects in recent years but there are very few examples in the field of archaeology. Especially how can we extract effective attributes from the two- or three-dimensional radar data so that we can map and describe numerous archaeological targets in a large cultural site? In this paper, we applied GPR attribute technology to investigate the ancient Nanzhao castle-site in Tengchong, Yunnan Province. In order to get better archaeological target (the ancient wall, the ancient kiln site, and the ancient tomb) analysis and description, we collated the GPR data by collected standardization and then put them to the seismic data processing and interpretation workstation. The data was processed, including a variety of GPR attribute extraction, analysis, and optimization and combined with the archaeological drilling data. We choose the RMS Amplitude, Average Peak Amplitude, Instantaneous Phase, and Maximum Peak Time to interpret three archaeological targets. By comparative analysis, we have clarified that we should use different attributes to interpret different archaeological targets and the results of attribute analysis after horizon tracking is much better than the results based on a time slice. 展开更多
关键词 GPR ATTRIBUTE archaeological investigation
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Paleocene Wuyun Flora in Northeast China: Amersinia and Beringiaphyllum of Cornaceae sensu
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作者 冯广平 Albert G ABLAEV +1 位作者 王宇飞 李承森 《Acta Botanica Sinica》 CSCD 2002年第4期481-487,共7页
Specimens of Amersinia obtrullata and Beringiaphyllum pseudoantiquum in Paleocene Wuyun flora, Heilongjiang Province, Northeast China, were described and assigned to Cornaceae sensu. Infructescences formally allocated... Specimens of Amersinia obtrullata and Beringiaphyllum pseudoantiquum in Paleocene Wuyun flora, Heilongjiang Province, Northeast China, were described and assigned to Cornaceae sensu. Infructescences formally allocated in Trochodendron sp. were reviewed and assigned to Amersinia obtrullata. Leaves described as Populus carneosa, Celastrophyllum subprotophyllum, Viburnum antiquum, V. asperum, Viburniphyllum finale, Protophyllum wuyunense, P. cf. haydenii, P. ovatifolium, Credneria inordinata were also restudied and assigned to Beringiaphyllum pseudoantiquum. 展开更多
关键词 Amersinia Beringiaphyllum CORNACEAE Paleocene
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Antioxidant and Antimicrobial Activities of Echinacea (Echinacea purpurea L.) Extracts Obtained by Classical and Ultrasound Extraction 被引量:2
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作者 Ivana Stanisavljevi Sаa Stojievi +2 位作者 Dragan Velikovi Vlada Veljkovi Miodrag Lazi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第3期478-483,共6页
Antioxidant and antimicrobial activities of Echinacea purpurea L. (Asteraceae) extracts obtained by classical and ultrasound solvent extraction were compared. The dry aerial part of plant was extracted by 70% etha-nol... Antioxidant and antimicrobial activities of Echinacea purpurea L. (Asteraceae) extracts obtained by classical and ultrasound solvent extraction were compared. The dry aerial part of plant was extracted by 70% etha-nol at a solid-to-liquid ratio of 1︰10 (m/v) and 25°C. The extract obtained by classical solvent extraction contained 29% larger amounts of phenolic compounds and 20% higher content of flavonoids. 2,2-diphenyl-1-picril hydrazyl radical (DPPH) scavenging reached 93.6% and the values of EC50 were (34.16±0.65) μg·ml-1 and (65.48±1.12) μg·ml-1 for the extracts obtained by the classical and ultrasound extractions, respectively. The extracts, independent of the extraction technique applied, showed a considerable growth inhibition on Candida albicans and Saccharo-myces cerevisiae, while no growth inhibition zones were observed for Aspergillus niger. The diameters of inhibition zone observed for all the microorganisms were larger for extracts obtained by classical extraction than those by ul-trasound extraction. 展开更多
关键词 antioxidant activity antimicrobial activity Echinaceapurpurea L. total phenols FLAVONOIDS extraction
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Nicotine enhances migration and invasion of human esophageal squamous carcinoma cells which is inhibited by nimesulide 被引量:3
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作者 Ye Zong Shu-Tian Zhang Sheng-Tao Zhu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第20期2500-2505,共6页
AIM: To study the effect of nicotine on the migration and invasion of human esophageal squamous carcinoma cells and to investigate whether nimesulide can inhibit the effect of nicotine.METHODS: The esophageal squamo... AIM: To study the effect of nicotine on the migration and invasion of human esophageal squamous carcinoma cells and to investigate whether nimesulide can inhibit the effect of nicotine.METHODS: The esophageal squamous carcinoma cell line (TE-13) was treated with different concentrations of nicotine (100 μg/mL and 200 μg/mL) or 200 μg/mL nicotine plus 100 μmol/L nimesulide. Cell migration and invasion were measured using migration and invasion chamber systems. COX-2 expression was determined by Western blotting. Matrix metalloproteinase-2 (MMP-2) was analyzed by zymography and ELISA.RESULTS: Nicotine (100 μg/mL, 200 μg/mL) enhanced TE-13 cells migration and invasion, and increased the protein expression of COX-2 and the activity of MMP-2. Nicotine (200 μ/mL) stimulated TE-13 cells migration and invasion which were partly blocked by nimesulide. This was associated with decreased protein expression of COX-2 and decreased activity and protein expression of MMP-2. CONCLUSION: Nicotine enhances the migration and invasion of the esophageal squamous carcinoma cell line, and nimesulide partly blocks the effect ofnicotine-enhanced esophageal squamous carcinoma cell migration and invasion. 展开更多
关键词 Carcinoma Cyclooxygenase 2 inhibitors ESOPHAGUS NICOTINE Squamous cell
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First report of subgenus Phoenicopsis(Czekanowskiales)from Middle Jurassic of Ordos,China and its paleoclimatic implications
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作者 LI Tao LI Yunfeng +3 位作者 NA Yuling HUANG Wei TAN Xiao SUN Chunlin 《Global Geology》 2015年第3期145-154,共10页
Subgenus Phoenicopsis (Phoenicopsis) assigned to Czekanowskiales is recognized and a new species, Phoenicopsis (Ph.) ordosensis sp. nov. is first reported fi'om the Middle Jurassic Yan'an Formation of the Ordos ... Subgenus Phoenicopsis (Phoenicopsis) assigned to Czekanowskiales is recognized and a new species, Phoenicopsis (Ph.) ordosensis sp. nov. is first reported fi'om the Middle Jurassic Yan'an Formation of the Ordos Basin, alternate based upon the leaf gross morphology and epidermal structures. The new species has linear leavs in bundles of five to six attached on a short shoot, more than 100 mm long by 5-6 mm wide, containing 10-12 parallel veins at upper portion. The leaf is hypostomatic. Epidermal cells are longitudinally arranged with smooth periclinal wall on the upper cuticle. The narrow non-stomatal zones and wide stomatal zones alternate in the lower cuticle. Stomata in four to five irregular spaced rows are longitudinally oriented in each stomatal zone. Guard cells for each are surrounded by four to five subsidiary cells with undeveloped papillae. Anticlinal wails of ordinal3, epidermal cells are nearly straight and periclinal walls slightly papillate. The new species shallow stomatal pits kept open and surrounded by unevenly undeveloped bulges. These characters are consistent with those of growth in a humid, rather than an arid climate. The presence of subgenus Phoenicopsis and other taxa of Czekanowskiales in the coal-bearing Yan'an Formation supports the view that the climate in the Ordos Basin was humid and warm with seasonal changes during the Middle Jurassic. 展开更多
关键词 Subgenus Phoenicopsis (Phoenicopsis) Czekanowskiales Middle Jurassic ORDOS China
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先秦时期湖北地区的民族和文化考察
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作者 杨东晨 杨建国 《长江文化论丛》 2002年第1期91-126,共36页
湖北古属《尚书·禹贡》所载荆州、豫州的一部分。隋开皇九年(589年)改郢州为鄂州,治所设在江夏(今武汉市武昌),辖境相当于今武汉长江以南部分、黄石市和咸宁地区,代表着湖北省的主要部分,遂简称鄂。它位于长江中游,与河南、陕西、... 湖北古属《尚书·禹贡》所载荆州、豫州的一部分。隋开皇九年(589年)改郢州为鄂州,治所设在江夏(今武汉市武昌),辖境相当于今武汉长江以南部分、黄石市和咸宁地区,代表着湖北省的主要部分,遂简称鄂。它位于长江中游,与河南、陕西、四川、湖南、江西及安徽等省接壤,清代始设湖北省,以位于洞庭湖之北而得名。湖北靠近中原,自古就是南北民族迁徙和文化交流之地,经济、文化比较进步。 展开更多
关键词 黄石市 湖北 部分 湖北省 地区 民族 古属 长江
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Environmental pressure rather than ongoing hybridization is responsible for an altitudinal cline in the morphologies of two oaks
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作者 Ichiro Tamaki Yae Yamada 《Journal of Plant Ecology》 SCIE CSCD 2020年第4期413-422,共10页
Aims In a contact zone between related taxa,phenotypic variation can result from genetic and/or environmental gradients.This study aimed to clarify the cause of phenotypic variation in leaf morphology of two Quercus c... Aims In a contact zone between related taxa,phenotypic variation can result from genetic and/or environmental gradients.This study aimed to clarify the cause of phenotypic variation in leaf morphology of two Quercus crispula varieties—crispula(QCC)and mongolicoides(QCM)—in their contact zone along an altitudinal gradient.Methods We measured 6 morphological traits of leaves and recorded genotypes of 13 nuclear microsatellite loci for 48 individuals in the contact zone and 24 individuals in each of the reference populations of QCC and QCM.We constructed a model explaining the phenotypic variation(leaf morphology)in relation to environmental(altitude)and genetic(ancestry from the reference population)gradients.Important Findings Both morphological and genetic markers distinguished the two varieties in the reference populations well.We were able to confirm the power of both morphological and genetic markers.Individuals within the contact zone population had intermediate ancestry that was slightly biased to QCM ancestry,and the distribution of their morphologies overlapped with those of the two varieties in the reference populations.The effect of altitude on leaf morphological traits was significant,while that of ancestry was not.Distributions of ancestry and interclass heterozygosity in the contact zone population resembled those in F2 or later generation hybrids.These results indicate that in the contact zone between QCC and QCM,there is no ongoing hybridization,but environmental pressure has created an altitudinal gradient in morphological traits through phenotypic plasticity and/or variation in functional genes. 展开更多
关键词 Quercus crispula Quercus mongolica leaf morphologies microsatellites hybrid zone
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Growth of a polymetallic nodule from northwestern continental margin of the South China Sea and its response to changes in paleoceanographical environment of the late Cenozoic 被引量:6
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作者 ZHANG ZhenGuo DU YuanSheng +4 位作者 WU ChangHang FANG NianQiao YANG ShengXiong LIU Jian SONG ChengBing 《Science China Earth Sciences》 SCIE EI CAS 2013年第3期453-463,共11页
In the northern South China Sea, the accumulation of enormous quantities of terrigenous sediment during Cenozoic rendered well-developed polymetallic nodules very rare. In this study, we analyzed a polymetallic nodule... In the northern South China Sea, the accumulation of enormous quantities of terrigenous sediment during Cenozoic rendered well-developed polymetallic nodules very rare. In this study, we analyzed a polymetallic nodule from the northwestern conti- nental margin of the South China Sea using microscopic mineralogical observation, electron probes, X-ray diffraction (XRD), ICP-MS, and Be isotope dating. We found the nodule's shell layers rich in different types of microstructures, including co- lumnar, laminar, stack-like, petal-like, and porphyritic structures. The major mineral components of the nodule are MnO2. Unlike nodules from the eastern Pacific basin, this nodule has high contents in Fe, Si, A1, and REEs but low contents in Mn, Cu, Co, and Ni. The Mn/Fe ratio is also low and the average REEs content is 1370.4 ppm. There is a strong positive anomaly of Ce; and the Be (beryllium) isotope dating shows the initial time of growth of the nodule to be about 3.29 Ma. The inner compact layer formed from 3.29 Ma to about 1.83 Ma. The laminar and stack-like structures and the low contents of the terri- genous elements such as Fe, Si, REE, and A1 indicate the paleoceanographical environment with weak undersea currents and favorable oxidizing conditions. From 1.83 Ma to 0.73 Ma, the growth rate of the nodule increased by about 3%; the micro- structures formed during this period are stack-like and columnar. The contents of Si and A1 are increased by nearly 10%, indi- cating an increase of terrigenous sediment input in the northern South China Sea. The content of Ce is decreased by about 16% indicating a significant weakening of the oxidizing conditions at the seabed. From 0.73 Ma to 0.69 Ma, the growth rate of the nodule rapidly rose up to 8.27 times that of the nodule's average growth rate, and the contents of Fe, A1, and REEs in the layer also increased, forming a loose layer characterized by oolitic, granular, porphyritic, and petal-like structures, indicating the paleoceanographical environment with a high sedimemtation rate and abundant supply of terrigenous sediment in the northern South China Sea. From 0.69 Ma to 0.22 Ma, the growth rate of the nodule suddenly slowed and the outer compact layer formed. Contents of Fe, Si, REE, A1, Mn, Cu, Co, and Ni in this layer were significantly lower than in other layers. The main structures of the layer are laminar and fissure filling structures. These reflect the paleoceanographical environment with stable undersea currents, poor oxidizing conditions, and other conditions not conducive to nodule growth. The growth process of nodule S04-1DG-1 was found to respond sensitively to the changes of the paleoceanographical environment of the northern South China Sea during the late Cenozoic. 展开更多
关键词 polymetallic nodules growth process late Cenozoic paleoceanographical environment RESPONSE northwestern conti-nental margin of South China Sea
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