Strontium isotope stratigraphy in the Late Cretaceous: Numerical calibration of the Sr isotope curve and intercontinental correlation for the campanian

The white Chalk exposed in quarries at Lagerdorf and Kronsmoor, northwestern Germany, provides a standard section for the European Upper Cretaceous. The Sr-87/Sr-86 values of nannofossil chalk and belemnite calcite increase upward through 330 m of section, from less than or equal to 0.70746 in the Upper Santonian to greater than or equal to 0.70777 in the Lower Maastrichtian. The data define three linear trends separated by major points of inflection at stratigraphic heights in the section of 162 m (75.5 Ma) in the Upper Campanian Galerites vulgaris zone and at -6 m (82.9 Ma), just above the base of the Campanian in the Inoceramus lingua/Goniateuthis quadrata zone. The temporal rate of change of Sr-87/Sr-86 was constant through each of the linear segments of our isotope ''curve'' when viewed at the resolution of our average sampling interval (0.15 m.y.). Fine structure, if rear, may record brief (<100 kyr) excursions of (SrSr)-Sr-87-Sr-86 from values expected from the overall trends. In Lagerdorf, the boundary between the Santonian and Campanian stages, taken here as the level of first occurrence of the belemnite Gonioteuthis granulataquadrata, has an Sr-87/Sr-86 Of 0.707473 +/- 5. This is within error of the values of 0.707457 +/- 16 for this boundary in the U.S. western interior (base of the Scaphites leei III zone) and 0.707479 +/- 9 for this boundary in the English Chalk (top of the Marsupites testudinarius zone). In Kronsmoor, the boundary between the Campanian and Maastrichtian stages, taken here as the level of first occurrence of the belemnite Belemnella lanceolata, has an Sr-87/Sr-86 of 0.707723 +/- 4. This is within error of the values of 0.707725 +/- 20 for this boundary in the U.S. western interior (base of the Baculites eliasi zone) and 0.707728 +/- 5 for this boundary in the English Chalk (defined as in Germany)

Experimental and numerical studies of the effects of a rail vibration absorber on suppressing short pitch rail corrugation

The effects of a rail vibration absorber on suppressing short pitch rail corrugation are studied. Firstly, a rail vibration field test is carried out to analyze the vibration response of the rail with and without the vibration absorbers. Secondly, based on the hypothesis that friction-induced self-excited vibration of a wheel-rail system causes rail corrugation; two finite element models of a wheel-rail system and a wheel-rail-absorber system are established and analyzed. Both sets of rail vibration test results and theoretical results show that the rail absorbers can effectively reduce the friction-induced self-excited vibration of the wheel-rail system in the frequency range of 200-800 Hz, which corresponds to frequencies of short pitch rail corrugation. This may be a main reason that the rail vibration absorber can suppress the formation of short pitch rail corrugation

A simple unsymmetric 4‐node 12‐DOF membrane element for the modified couple stress theory

In this work, the recently proposed unsymmetric 4‐node 12‐DOF (degree‐of‐freedom) membrane element (Shang and Ouyang, Int J Numer Methods Eng 113(10): 1589‐1606, 2018), which has demonstrated excellent performance for the classical elastic problems, is further extended for the modified couple stress theory, to account for the size effect of materials. This is achieved via two formulation developments. Firstly, by using the penalty function method, the kinematic relations between the element's nodal drilling DOFs and the true physical rotations are enforced. Consequently, the continuity requirement for the modified couple stress theory is satisfied in weak sense, and the symmetric curvature test function can be easily derived from the gradients of the drilling DOFs. Secondly, the couple stress field that satisfies a priori the related equilibrium equations is adopted as the energy conjugate trial function to formulate the element for the modified couple stress theory. As demonstrated by a series of benchmark tests, the new element can efficiently capture the size‐dependent responses of materials and is robust to mesh distortions. Moreover, as the new element uses only three conventional DOFs per node, it can be readily incorporated into the standard finite element program framework and commonly available finite element programs

Thermal evolution history after collision of North China plate with Yangtze plate

对采自苏北一胶南一大别高压变质构造混杂岩带的片麻岩、糜棱岩和郑庐断裂带上的片麻岩中9个钾长石进行了40Ar-39Ar 年龄测定和多重扩散域(MDD)模式处理, 9个样品的热演化史表明上述地区存在5个不同的快速冷却时段, 并就其可能的构造含义, 提出了华北与扬子板块碰撞后的折返历史过程。40Ar-39Ar analyses and MDD（multiple diffusion domain）model treatements were performed for 9 K-feldspar samples. They were collected from gneiss and mylonite of North Jiangsu-Jiaonan-Dabie tectonic melange belt and Tancheng-Lujiang fault zone. The thermal evolution history exhibits five fast ccoling stages found in these samples．In relation with their possible tectonic implications a recovery process after the collision of the North China plate with the Yangtze plate is suggested here.published_or_final_versio

华北克拉通北缘晚中生代火山岩Sr-Nd-Pb同位素填图及其构造意义

辽宁西部广泛分布着晚中生代火山岩，横跨华北克拉通和兴> 蒙造山带两大构造单元，一般认为它们是以在这一地区发育的两条主要断裂———西拉木伦河断裂和赤峰> 开源断裂为界。这些火山作用曾被认为是中生代伊泽奈崎板块西向或西北向消减作用的结果。在岩性上它们主要以中酸性岩石为主，玄武岩等中基性岩石较少。为查明下伏岩石圈对这些岩浆作用成因的影响，对其中的SiO2 含量 开源断裂两侧为界，两侧火山岩的同位素特征存在显著区别。南区有明显的EMI 特征并具EMI-PM 混合趋势，而北区则显示了原始或略亏损的特征。南北两区之间的过渡带（介于西拉木伦河断裂和赤峰> 开源断裂之间）则表现了同位素组成上相应的过渡特征。这一地球化学观测与已有的地质和地球物理资料颇为吻合。基于新生代幔源岩石化学反演的中国东部陆下地幔化学区划研究揭示了克拉通下(subcratonic)岩石圈地幔与EMI 存在着密切关系。本研究所提供的地球化学证据说明了采用中生代中基性岩类作为类似研究途径的可行性，并进一步提出对华北克拉通边缘中生代火山作用成因另一种可能的解释，即古消减带物质的活化有可能对华北北缘火山岩源区物质组成产生重要影响。Late Mesozoic volcanic rocks are extensively spread on both sides of northern margin of the North China Craton (NCC), where is the boundary between an Archean craton to the south and a Paleozoic orogenic belt, Xing an- Mongolia Orogenic Belt (XMOB), to the north. Two major east- west trending faults, Kaiyuan- Chifeng Fault (KCF) and Xar Moron He Fault (XHF) develop in this margin zone as a boundary between two tectonic domains. The volcanism has been thought to be the magmatic response to the west- , or no...published_or_final_versio

Gender differences in outcomes in people with schizophrenia in rural China: 14-year follow-up study

postprin

Promoter hypermethylation and histone hypoacetylation contribute to pancreatic-duodenal homeobox 1 silencing in gastric cancer

Background and Aims: The expression of pancreatic-duodenal homeobox 1 (PDX1) in gastric cancer is aberrantly reduced. The aim of this study was to elucidate the regulation of DNA methylation and histone acetylation at the promoter for PDX1 silencing in gastric cancer. Methods: PDX1 expression in response to demethylation and acetylation was detected in human gastric cancer cell lines by reverse transcription-polymerase chain reaction (PCR) and western blot. Four CpG islands within the 5#-flanking region of PDX1 gene were analyzed with their transcription activities being detected by dual luciferase assay. Promoter hypermethylation was identified in gastric cancer cell lines and cancer tissues by methylation-specific PCR or bisulfite DNA sequencing PCR analysis. Histone acetylation was determined by chromatin immunoprecipitation (ChIP) assay. Results: Demethylation by 5′-aza-2′-deoxycytidine (5′-aza-dC) and/or acetylation by trichostatin A (TSA) restored PDX1 expression in gastric cancer cells. Hypermethylation was found in four CpG islands in six of seven cancer cell lines. However, only the distal CpG island located in the promoter fragment of PDX1, F383 (c.22063 to 21681 nt upstream of the ATG start codon) displayed significant transcriptional activity that could be suppressed by SssI methylase and increased by 5′-aza-dC and TSA. More than 70% of the single CpG sites in F383 were methylated with hypermethylation of F383 fragment more common in gastric cancerous tissues compared with the paired normal tissues (P < 0.05). ChIP assay showed F383 was also associated with low hypoacetylation level of the histones. Conclusion: Promoter hypermethylation and histone hypoacetylation contribute to PDX1 silencing in gastric cancer. © The Author 2010. Published by Oxford University Press. All rights reserved.postprin

燒炭自殺在東亞國家的流行散佈: 趨勢分析

The Abstract Book can be viewed at: http://www.sop.org.tw/book/download/Summary2013.pdfConference Theme: Focusing on Mental Health, Life Care and Social Network in the ElderlyObjective: Suicides by carbon monoxide poisoning resulting from burning barbecue charcoal reached epidemic levels in Hong Kong and Taiwan within 5 years in the early 2000s. Methods: We used data for suicides by gases other than domestic gas in Hong Kong, Japan, South Korea (1995-2010), Taiwan (1995-2011), and Singapore (1996-2011) to systematically investigate the spread of this method in East Asia. Graphical and joinpoint regression analyses were used to examine suicide trends and Poisson regression analysis to study sex- and age-specific patterns. Results: In 1995/1996, charcoal-burning suicides accounted for < 1% of all suicides in all study countries, except around 5% in Japan, but they increased to account for 14%, 28%, 13%, 4.3%, and 3.4% of all suicides in Hong Kong, Taiwan, Japan, South Korea, and Singapore respectively in 2010. Rises were first seen in Hong Kong in 1999, followed by Singapore in 2000, Taiwan in 2001, Japan in 2003, and South Korea in 2008. There was some evidence for an impact on overall suicide trends in Hong Kong, Taiwan, and Japan (females), but not in Japan (males), South Korea, and Singapore. Rates of change did not differ by sex/age group in Taiwan and Hong Kong but were greatest in young people in Japan and middleaged men and young women in South Korea. Conclusion: Variations in the timing, scale and sex/age pattern of the epidemic appear to be influenced by the media reporting of charcoal-burning suicide, whilst other factors such as the characteristics of the first or first few cases, language and ulture, familiarity and accessibility with the method, and socio-economic conditions may also play a role. Strategies to limit the epidemic spread of new suicide methods include surveillance to enable the early identification of the emergence of such methods, responsible media reporting and restrictions on Internet sites giving technical information about the method