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1.
Isozaki Y Yao J Ji Z Saitoh M Kobayashi N Sakai H 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2008,84(8):344-353
The Capitanian (Late Guadalupian) Maokou Formation at Chaotian in northern Sichuan, South China, is composed mainly of shallow marine shelf carbonates deposited on the Tethyan side of South China. By detailed field mapping and scientific drilling, we newly found out unique fossil assemblages and a sharp lithologic change in the upper part of the Maokou Formation. The main part of the Maokou Formation (over 130 m thick) is composed of algal packstone with Wordian-Capitanian large-tested fusulines, rugose corals and other sessile benthos, whereas the Uppermost Member (13 m thick) is composed of black limy mudstone/chert with Capitanian offshore biota (ammonoids, radiolarians, and conodonts). The topmost Capitanian conodont zones are missing; however, the Maokou Formation is disconformably overlain by 260+/-4 Ma volcanic ash (Wangpo bed) and the Early Lopingian Wujiaping Formation with plant-bearing coaly mudstone and shallow marine carbonates (packstone). The newly identified facies change indicates that northern Sichuan has experienced rapid sea-level changes in the late Guadalupian, i.e., first a transgression in the mid-Capitanian and then a regression across the Guadalupian-Lopingian boundary. As the end-Guadalupian is characterized by a global regression, such a volatile sea-level fluctuation, in particular the sea-level rise, is unique to the Tethyan side of South China. The newly recognized relatively deep-water late Guadalupian sequence adds new paleo-environmental information and further provides a paleotectonic interpretation of the low-latitude eastern Tethyan margin immediately before the end-Guadalupian mass extinction. 相似文献
2.
Ryugo S. HAYANO Ryutaro ADACHI 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2013,89(5):196-199
The first objective data showing the geographical locations of people in Fukushima after the Fukushima Dai-ichi nuclear power plant accident, obtained by an analysis of GPS (Global Positioning System)-enabled mobile phone logs, are presented. The method of estimation is explained, and the flow of people into and out of the 20 km evacuation zone during the accident is visualized. 相似文献
3.
Following Morris’s [5] consideration of a sourceless abelian gauge string in a Robertson-Walker universe with flat space sections
we have generalized the treatment to the case of arbitrary spatial curvature. We find that creation or destruction of the
gauge string is not possible if the spatial curvature is nonzero. 相似文献
4.
Both single crystals of VCl3(THF)3 as well as isotypic cocrystals of the composition MCl3(THF)3, M=Ti/V 1/3, undergo a topotactic reversible phase transition to a hitherto unknown low-temperature modification. The close relationship between this new structure and the room-temperature phase determined by Cottonet al. is discussed from the molecular and the intermolecular point of view: Both modifications are built up by conformationally very similar molecules which change their arrangement during the phase transition. Lattice energy calculations confirm that these two alternative arrangements correspond to minima of almost the same packing energy.Dedicated to Professor Dr. G. E. Herberich on the occasion of his 60th birthday. 相似文献
5.
报道了2886名正常儿童与718例反复呼吸道感染儿童头发中微量元素含量对比研究结果。研究表明,患儿的身高、体重和发Zn明显低于正常儿童,而发Cu、Ca、Pb则明显高于正常和童。因子提取分析显示,Zn和Pb在儿童反复呼吸道感染发病中起非常重要的作用。患反复呼吸道感染儿童约占儿童总数的20%左右。 相似文献
6.
The content and isotopic compositions of different sulphur species in pore-water and solid phases have been examined on five sediment cores taken from muddy sediment region in the Yellow Sea and the East China Sea. Relationships among these data have been investigated with the combination of morphology of mineral pyrite and organic matter so as to role out the diagenetic behaviour of sulphur species at the early stage of diagenesis in modern marine sediment and the origin of pyrite formation. 相似文献
7.
Simon G. Bott Ulrich Kynast Jerry L. Atwood 《Journal of inclusion phenomena and macrocyclic chemistry》1986,4(3):241-246
18-crown-6 reacts with TiCl3 in CH2Cl2 to form a complex in which the crown ether functions as a tridentate ligand. Addition of moist hexane affords a molecular complex in which the crown ether functions as a bidentate ligand. A water molecule is bonded directly to the titanium atom and is further hydrogen bonded to three of the oxygen atoms of the crown. The deep blue crystals of the CH2Cl2 adduct belong to the monoclinic space groupP21/n witha=13.481(8),b=8.021(5),c=21.425(9) Å, =97.32(5)°, and
calc = 1.51 g cm–3 forZ=4. Refinement led to a conventionalR value of 0.040 based on 873 observed reflections. The Ti–O bond distances for the crown oxygen atoms are 2.123(8) and 2.154(9) Å, while the oxygen atom of the water molecule is bonded at 2.072(8) Å. The octahedral coordination sphere of the titanium atom is completed by the three chlorine atoms at distances of 2.340(5), 2.352(4), and 2.373(4) Å.
Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82034 (10 pages). 相似文献
8.
Kim SH Song JY Joo EJ Lee KY Shin SY Lee YH Ahn YM Kim YS 《Experimental & molecular medicine》2012,44(2):121-129
The early growth response gene 2 (EGR2) is located at chromosome 10q21, one of the susceptibility loci in bipolar disorder (BD). EGR2 is involved in cognitive function, myelination, and signal transduction related to neuregulin-ErbB receptor, Bcl-2 family proteins, and brain-derived neurotrophic factor. This study investigated the genetic association of the EGR2 gene with BD and schizophrenia (SPR) in Korea. In 946 subjects (350 healthy controls, 352 patients with BD, and 244 with SPR), nine single nucleotide polymorphisms (SNPs) in the EGR2 gene region were genotyped. Five SNPs showed nominally significant allelic associations with BD (rs2295814, rs61865882, rs10995315, rs2297488, and rs2297489), and the positive associations of all except rs2297488 remained significant after multiple testing correction. Linkage disequilibrium structure analysis revealed two haplotype blocks. Among the common identified haplotypes (frequency > 5%), 'T-G-A-C-T (block 1)' and 'A-A-G-C (block 2)' haplotypes were over-represented, while 'C-G-G-T-T (block 1)' haplotype was under-represented in BD. In contrast, no significant associations were found with SPR. Although an extended analysis with a larger sample size or independent replication is required, these findings suggest a genetic association of EGR2 with BD. Combined with a plausible biological function of EGR2, the EGR2 gene is a possible susceptibility gene in BD. 相似文献
9.
GEChendong O.Slaymaker T.F.Pedersen 《科学通报(英文版)》2003,48(21):2357-2361
Pb geochronology and sediment core profiles of organic carbon, total sulfur and organic carbon isotope (d 13C) values were used to reconstruct the local environ-mental history of the Shamei Lagoon, located in the Wan-quan River Estuary, eastern Hainan Island, China. Totalsulfur and d 13C values decreased upwards in the top 30 cm of a sediment core that spanned the last 200 years of deposi-tion. Total sulfur concentration and d 13C values respectively decreased upward from 1.92% to 0.36%, and -20.63?to -23.64? The C/S ratio in the 19th century and earlier was relatively stable in the range of 0.47—0.80, and there was a positive correlation between organic carbon and total sulfur. Since around 1900 AD, the C/S ratio increased rapidly to a maximum of 3.94, but no simple correlation was found be-tween organic carbon and total sulfur during this more re-cent period. These results indicated that before 1800 AD, the lagoon had a fully marine character, and the location of to-day抯 Wanquan River Estuary was an open embayment.From 1800 to 1900, the salinity of Shamei Lagoon decreased noticeably. The amount of seawater which could enter thelagoon decreased gradually as the Yudai spit grew. Today,seawater scarcely affects the lagoon; it is essentially a fresh-water basin. 相似文献
10.