Prediction of individual genetic risk to prostate cancer using a polygenic score

BACKGROUND Polygenic risk scores comprising established susceptibility variants have shown to be informative classifiers for several complex diseases including prostate cancer. For prostate cancer it is unknown if inclusion of genetic markers that have so far not been associated with prostate cancer risk at a genome-wide significant level will improve disease prediction. METHODS We built polygenic risk scores in a large training set comprising over 25,000 individuals. Initially 65 established prostate cancer susceptibility variants were selected. After LD pruning additional variants were prioritized based on their association with prostate cancer. Six-fold cross validation was performed to assess genetic risk scores and optimize the number of additional variants to be included. The final model was evaluated in an independent study population including 1,370 cases and 1,239 controls. RESULTS The polygenic risk score with 65 established susceptibility variants provided an area under the curve (AUC) of 0.67. Adding an additional 68 novel variants significantly increased the AUC to 0.68 (P = 0.0012) and the net reclassification index with 0.21 (P = 8.5E-08). All novel variants were located in genomic regions established as associated with prostate cancer risk. CONCLUSIONS Inclusion of additional genetic variants from established prostate cancer susceptibility regions improves disease prediction. Prostate 75:1467–1474, 2015. © 2015 Wiley Periodicals, Inc.

Design, synthesis and docking studies of new quinoline-3-carbohydrazide derivatives as antitubercular agents

Three new series of 4-hydroxy-8-trifluoromethyl-quinoline derivatives were synthesized through multi step reactions. All the newly synthesized compounds were characterized by spectral and elemental analyses. The structure of 5j was evidenced by X-ray crystallographic study. The newly synthesized title compounds were evaluated for their antimicrobial activities including antimycobacterial activity. Amongst the tested compounds, 5b, 5e, 5h, 5j, 6c and 7c displayed promising antimicrobial activity. The mode of action of these active compounds was carried out by docking of receptor enoyl-ACP reductase with newly synthesized candidate ligands, 5b, 5e, 5h, 5j and 6c. (C) 2011 Elsevier Masson SAS. All rights reserved.

Hybrid molecules of carvacrol and benzoyl urea/thiourea with potential applications in agriculture and medicine

Benzoyl phenyl urea, a class of insect growth regulator's acts by inhibiting chitin synthesis. Carvacrol, a naturally occurring monoterpenoid is an effective antifungal agent. We have structurally modified carvacrol (2-methyl-5-1-methylethyl] phenol) by introducing benzoylphenyl urea linkage. Two series of benzoylcarvacryl thiourea (BCTU, 4a-f) and benzoylcarvacryl urea (BCU, 5a-f) derivatives were prepared and characterized by elemental analysis, IR, H-1 and C-13 NMR and Mass spectroscopy. Derivatives 4b, 4d, 4e, 4f and 5d, 5f showed comparable insecticidal activity with the standard BPU lufenuron against Dysdercus koenigii. BCTU derivatives 4c, 4e and BCU 5c showed good antifungal activity against phytopathogenic fungi viz. Magnaporthe grisae, Fusarium oxysporum, Dreschlera oryzae; food spoilage yeasts viz. Debaromyces hansenii, Pichia membranifaciens; and human pathogens viz. Candida albicans and Cryptococcus neoformans. Compounds 5d, 5e and 5f showed potent activity against human pathogens. Moderate and selective activity was observed for other compounds. All the synthesized compounds were non-haemolytic. These compounds have potential application in agriculture and medicine. (C) 2012 Elsevier Ltd. All rights reserved.

Synthesis of Novel Benzofuran-Gathered C-2,4,6-substituted Pyrimidine Derivatives Conjugated by Sulfonyl Chlorides: Orally Bioavailable, Selective, Effective Antioxidants and Antimicrobials Drug Candidates

In the present study, we have made an effort to develop the novel synthetic antioxidants and antimicrobials with improved potency. The novel benzofuran-gathered C-2,4,6-substituted pyrimidine derivatives 5a, 5b, 5c, 5d, 5e, 5f, 6a, 6b, 6c, 6d, 6e, 6f, 7a, 7b, 7c, 7d, 7e, 7f, 8a, 8b, 8c, 8d, 8e, 8f, 9a, 9b, 9c, 9d, 9e, 9f were synthesized by simple and efficient four-step reaction pathway. Initially, o-alkyl derivative of salicylaldehyde readily furnish corresponding 2-acetyl benzofuran 2 in good yield, upon the treatment with potassium tertiary butoxide in the presence of molecular sieves. Further, Claisen-Schmidt condensation with aromatic aldehydes via treatment with thiourea followed by coupling reaction with different sulfonyl chlorides afforded target compounds. The structures of newly synthesized compounds were confirmed by IR, H-1 NMR, C-13 NMR, mass, and elemental analysis and further screened for their antioxidant and antimicrobial activities. The results showed that the synthesized compounds 8b, 8e, 9b, and 9e produced significant antioxidant activity with 50% inhibitory concentration higher than that of reference, whereas compounds 7d and 7c produced dominant antimicrobial activity at concentrations 1.0 and 0.5mg/mL compared with standard Gentamicin and Nystatin, respectively.

Mitochondria-Targeting Iron(III) Catecholates for Photoactivated Anticancer Activity under Red Light

Iron(III) catecholates Fe(R-bpa)(R-dopa)Cl] (1, 2) with a triphenylphosphonium (TPP) moiety, where R-bpa is 2-(TPP-N,N-bis((pyridin-2-yl)methyl)ethanamine) chloride (TPPbpa) and R-dopa is 4-{2-(anthracen-9-yl)methylamino]ethyl}benzene-1,2-diol (andopa, 1) or 4-{2-(pyren-1-yl)-methylamino]ethyl}benzene-1,2-diol (pydopa, 2), were synthesized and their photocytotoxicity studied. Complexes 3 and 4 with phenyl-N,N-bis(pyridin-2-yl)methyl]methanamine (phbpa) were used as controls. The catecholate complexes showed an absorption band near 720 nm. The 5e(-) paramagnetic complexes showed a Fe-III/Fe-II irreversible response near -0.45 V and a quasi-reversible catechol/semiquinone couple near 0.5 V versus saturated calomel electrode (SCE) in DMF/0.1 M tetrabutylammonium perchlorate. They showed photocytotoxicity in red/visible light in HeLa, HaCaT, MCF-7, and A549 cells. Complexes 1 and 2 displayed mitochondrial localization, reactive oxygen species (ROS) generation under red light, and apoptotic cell death. Control complexes 3 and 4 exhibited uniform distribution throughout the cell. The complexes showed DNA photocleavage under red light (785 nm), forming hydroxyl radicals as the ROS.

Alfabetização & letramento: conceitos fundamentais para uma efetiva prática de leitura

O objetivo dessa pesquisa é a análise das práticas de leitura realizadas no processo de aquisição da língua escrita, considerando as denominadas práticas de alfabetização realizadas no 1 segmento do Ensino Fundamental I às práticas de letramento no Ensino Fundamenta lI. Especificamente, será analisado o desempenho dos estudantes da E. M. Sobral Pinto, situada em Jacarepaguá, Zona Oeste, do Município do Rio de Janeiro. Esta escola é matriz naquela região, recebendo estudantes que terminaram o Ensino Fundamental I 1 ao 5 ano de escolaridade. Para fins do objetivo proposto, realiza-se uma análise triangulada, cujos vértices são os seguintes: a) análise da prova de leitura bimestral aplicada pelo SME semestralmente. b) análise das respostas docentes ao questionário aplicado cujo objetivo é discutir sobre os conceitos de leituras, alfabetização e letramento, cerne da pesquisa. c) Os dados referentes às planilhas de resultados das provas bimestrais referentes ao 1 e 4 bimestres de 2013, concernentes a cerca de 300 alunos E. M. Sobral Pinto, do 6 ano de escolaridade. A análise reforça os resultados exarados pela SME que revelam maioria absoluta de estudos com rendimento regular e/ou insuficiente em leitura, contrapondo-se a ínfimo percentual de estudantes com rendimento muito bom ou proficiente em leitura. As razões para os resultados estão centradas em uma abordagem de língua que se distancia das teorias linguísticas em perspectiva sociointeracionista

Identification and characterization of hypoxia-induced genes in Carassius auratus blastulae embryonic cells using suppression subtractive hybridization

Organisms living in water are inevitably exposed to periods of hypoxia. Environmental hypoxia has been an important stressor having manifold effects on aquatic life. Many fish species have evolved behavioral, physiological, biochemical and molecular adaptations that enable them to cope with hypoxia. However, the molecular mechanisms of hypoxia tolerance in fish, remain unknown. in this study, we used suppression subtractive hybridization to examine the differential gene expression in CAB cells (Carassius auratus blastulae embryonic cells) exposed to hypoxia for 24 h. We isolated 2100 clones and identified 211 differentially expressed genes (e-value <= 5e-3; Identity > 45%). Among the genes whose expression is modified in cells, a vast majority involved in metabolism, signal transduction, cell defense, angiogenesis, cell growth and proliferation. Twelve genes encoding for ERO1-L, p53, CPO, HO-1, MKP2, PFK-2, cystatin B, GLUT1, BTG1, TGF beta 1, PGAM1, hypothetical protein F1508, were selected and identified to be hypoxia-induced using semi-quantitive RT-PCR and real-time PCR. Among the identified genes, two open reading frames (ORFs) encoding for CaBTG1 and Cacystatin B were obtained. The deduced amino acid sequence of CaBTG1 had 94.1%, 72.8%, 72.8%, 72.8%, 68.6% identity with that of DrBTG1, HsBTG1, BtBTG1, MmBTG1 and XIBTG1. Comparison of Cacystatin B with known cystatin B, the molecules exhibited 49.5 to 76.0% identity overall. These results may provide significant information for further understanding of the adaptive mechanism by which C. auratus responds to hypoxia. (c) 2008 Elsevier Inc. All rights reserved.

Research on metallic ion beam production at IMP

Since 1998, many experiments for metallic ion production have been done on LECR2 (Lanzhou ECR ion source NO.2), LECR3 (Lanzhou ECR ion source NO.3) and SECRAL (Superconductiong ECR ion source Advanced design in Lanzhou) at Institute of Modern Physics. The very heavy metallic ion beams such as those of uranium were also produced by the plasma sputtering method, and supplied for HIRFL (Heavy Ion Research Facility in Lanzhou) accelerators successfully. During the test, 11.5e mu AU(28+), 9e mu AU(24+) were obtained. Some ion beams of the metal having lower melting temperature such as Ni and Mg ion beams were produced by oven method on LECR3 too. The consumption rate was controlled to be lower for Mg-26 ion beams production, and the minimum consumption was about 0.3mg per hour. In this paper, the main experimental results are given. Some discussions are made for some experimental phenomena and results, and some conclusions are drawn.

Multi-electron processes in 4.15-11.08 keV/u(13)C(6+) on argon collisions

The relative partial cross sections for C-13(6+)-Ar collisions at 4.15-11.08 keV/u incident energy are measured. The cross-section ratios sigma(2E)/sigma(SC), sigma(3E)/sigma(SC), sigma(4E)/sigma(SC) and sigma(5E)/sigma(SC) are approximately the constants of 0.51 +/- 0.05, 0.20 +/- 0.03, 0.06 +/- 0.03 and 0.02 +/- 0.01 in this region. The significance of the multi-electron process in highly charged ions (HCIs) with argon collisions is demonstrated (sigma(ME)/sigma(SC) as high as 0.79 +/- 0.06). In multi-electron processes, it is shown that transfer ionization is dominant while pure electron capture is weak and negligible. For all reaction channels, the cross-sections are independent of the incident energy in the present energy region, which is in agreement with the static characteristic of classic models, i.e. the molecular Coulomb over-the-barrier model (MCBM), the extended classical over-the-barrier (ECBM) and the semiempirical scaling laws (SL). The result is compared with these classical models and with our previous work of C-13(6+)-Ne collisions

Computer simulation of human iodothyronine deiodinase single-chain antibody

Iodothyronine plays a major role in growth, basic metabolism and organ formation. It has an extremely limited source in the body. In this thesis, we designed iodothyronine(T4) as hapten. Then a single chain antibody displayed on phange was obtained from a human phage displaying a single chain antibody library. The specific genes of E3 was subcloned in P-5E vector. According to its amino acid sequences, we simulate its three dimention structure by computer. It has never been reported in PDB.

The variation of upper ocean structure and paleoproductivity in the Kuroshio source region during the last 200 kyr

A core from the source region of the Kuroshio warm current (east of the Luzon Island) was analyzed using several proxies in order to study the variability of the Western Pacific Warm Pool (WPWP) during the last two glacial-interglacial cycles. Primary productivity (PP) variations were deduced from variations in the coccolith flora. Primary productivity was higher during glacial periods (the end of Marine Isotope Stage [MIS] 3, some periods in MIS 2 and 6), and decreased during interglacial periods (MIS 7, MIS Se and probably MIS 5c-5d), with the lowest PP in MIS 5e. variations in the delta C-13 difference in benthic and bulk carbonate, thus in the vertical gradient of delta C-13 in dissolved inorganic carbon (Delta delta C-13(c). (wuellerstorfi-N. dutertrei) and Delta delta C-13(c.) (wuellerstorfi-coccolith)) Coincided With the PP Changes, showing that export productivity was low during interglacial periods (MIS 7, MIS 5e and Holocene) and high during glacial periods (MIS 6, probably MIS 5c-5d, late MIS 4 and late MIS 3). Comparison of foraminiferal carbonate dissolution indicators and PP changes reveals that nannofossil assemblage in core Ph05-5 is not sensitive to carbonate dissolution intensity. The depth of the thermocline (DOT) was estimated from planktonic forminiferal assemblages, and was relatively greater during interglacial periods (MIS 7, MIS 5e, probably MIS 5c and Holocene) than during glacials (middle MIS 6, probably MIS 5b and 5d, some periods in MIS 4, MIS 3 and MIS 2). Good coherence between the paleoproductivity records and the DOT suggests that the DOT changes could be the primary control factor in changes of paleoproductivity, and the glacial high productivity in the Kuroshio source region could be associated with a global increase of nutrient concentration in the intermediate waters that upwelled into the photic zone. The low CO2 values derived for intervals of high productivity and a relatively shallow DOT suggest that the changes in biological productivity and DOT in the equatorial Pacific could have modified atmospheric CO2 concentrations. High Sea Surface Temperatures (SSTs) during the warm MIS 5e in combination with intensified monsoonal rain fall could have resulted in a more intense stratification of the upper waters, resulting in low nutrient supply to the surface waters and a resulting decrease in productivity. (C) 2010 Elsevier B.V. All rights reserved.

末次冰消期以来东亚季风演化：来自东海和北黄海沉积孢粉记录

本论文通过对冲绳海槽南部的MD05-2908孔、北黄海的B-U35、B-U41、B-L44孔和北黄海的299份表层样中的孢粉组成、堆积速率、有机碳氮同位素的综合研究，分析了北黄海的孢粉来源、传播动力和途径，并与其它古气候记录对比，重建了末次冰消期以来东亚季风的演化。 MD05-2908孔孢粉组合特征显示6800-3800a BP间气候温暖干燥，其间存在着两次明显的温度降低、湿度增加阶段，即6800-6600a BP和5800-4850a BP；3800a BP以后，气候变得比较寒冷湿润，中世纪暖期和小冰期分别位于990-480a BP和480-230a BP。 北黄海表层孢粉百分含量等值线图显示北黄海不同海域孢粉来源不同，北黄 海东部海域(123.5°E以东的陆架区域)孢粉主要来源于鸭绿江；北黄海中部海域(123.5°E-122.6°E的陆架区域)孢粉来源比较复杂，既有来自辽东半岛、沿海岛屿、山东半岛，还有由黄海暖流携带而来的；北黄海西部海域(122.6°E以西的陆架区域)孢粉以黄海沿岸流携带而来的黄河来源的为主。 北黄海表层孢粉百分含量等值线图还显示，北黄海东部海域孢粉分布主要受 鸭绿江冲淡水影响，波浪和潮汐的作用较弱；北黄海中部海域孢粉分布受黄海暖流和辽东沿岸流的分支共同影响；黄海暖流与黄海沿岸流在山东半岛东北部相遇，形成一逆时针方向的涡旋，该涡旋控制着北黄海西部海域孢粉的分布。 B-U35孔、B-U41和B-L44孔孢粉组合特征显示，12830-12350a BP时气候 寒冷干燥，植被以旱生草本植物为主，时间上可能对应YD事件；12350-10100a BP时植被以针叶林为主，林下生长着大量蕨类植物，气候寒冷湿润，可能对应着YD事件；10100-6600a BP时植被以落叶阔叶林为主，伴生大量旱生草本植物，气候温暖干燥；6600-5000a BP时植被以针叶-落叶阔叶混交林为主，旱生草本植物含量下降，相对上一阶段温度有所降低，但气候更湿润，可能对应全新世最佳期；5000-4000a BP时针叶林所占比例扩大，温度再次降低，湿度变化不明显；4000-500a BP旱生草本植物含量增加，气候寒冷干燥；500a BP-至今，受人类活动影响，植被遭到严重破坏。 B-U35孔和B-U41孔淡水水生植物花粉百分含量曲线显示11750a BP以来黄河河口地区沼泽湿地面积几经变化。10100-6600a BP时沼泽湿地范围在上一阶段的基础上进一步扩大；6600-2850a BP间沼泽湿地大面积缩小，水生植物属种式微；2850a BP之后黄河河口地区沼泽湿地面积再次扩大，水生植物重新繁盛。 MD05-2908孔蕨类孢子百分含量被用来作为中国东南部季风演化的代用指标。结果显示6800-3800a BP时夏季风较强，其间有两次夏季风减弱阶段，分别位于6800-6600a BP和5800-4850a BP，3800a BP以来，夏季风明显减弱，此期的夏季风减弱除受太阳辐射量的减少影响外，可能还与El Nino的频繁爆发有关。 B-U35孔和B-U41孔蒿属、藜科、麻黄科百分含量被用来作为中国中北部夏季风演化的代用指标。研究表明，11750a BP以来东亚夏季风强度在10100-6600a BP时，显著加强，6600a BP左右，夏季风开始减弱，4000a BP以后夏季风显著减弱。 将MD05-2908孔、B-U35孔和B-U41孔夏季风代用指标进行对比发现，中晚全新世以来中国南-北湿度变化特征正好相反，东亚夏季风强度变化以及由此引起的雨锋的南进北撤可能是导致中国不同区域中晚全新世以来降雨量不同的主要原因。

热带西太平洋边缘晚第四纪以来的古环境研究

利用取自热带太平洋边缘的5个柱状岩芯Ph05-5、WP3、MD2908、Z14-6和WP7，通过对其微体古生物和生物地球化学成分的分析，结合浮游有孔虫氧、碳同位素数据、AMS14C测年结果和已有的研究资料，分别研究了热带西太平洋边缘晚第四纪以来的钙质超微化石群落特征、碳酸盐旋回、超微化石氧碳同位素特征、古生产力和上层海水结构演化以及高分辨率东亚夏季风指标，并探讨了碳酸盐旋回、古生产力和上层海水结构演化、全新世东亚夏季风强弱变化的控制机制，以及钙质超微化石下透光带属种Florisphaera profunda的相对百分含量变化在热带太平洋边缘的古环境指示意义及不同环境条件下的控制机制。 西菲律宾海Ph05-5岩芯和台湾东南部WP3岩芯中CaCO3和钙质超微化石碳酸盐溶解指数、初级生产力指标的变化显示约190 kyr BP以来CaCO3含量整体上都表现为冰期高、间冰期低的“太平洋型”旋回特征，但菲律宾以东海区在末次冰期（MIS 4~2期）内部又显示出间冰段含量高、冰段含量低的“大西洋型”旋回特征。碳酸盐旋回的主要控制因素在菲律宾以东海区是碳酸盐溶解作用，而台湾东南海区则是初级生产力变化引起的钙质生物输入量的波动。 西菲律宾海Ph05-5岩芯中190 kyr BP以来的钙质超微化石δ18O值在末次间冰期（MIS 5e）和全新世明显低于末次冰期（MIS 5d~2）和倒数第二次冰期（MIS 6）。超微化石δ18O值与浮游和底栖有孔虫δ18O值都呈明显的正相关关系，但是超微化石的δ18O平均值重于表层浮游有孔虫Globigeriniodes rubber，轻于中层Neogloboquadrina dutertrei。超微化石δ13C值变化与其绝对丰度变化表明西菲律宾海区大约在MIS 6和MIS 5e期，表层海水初级生产力相当稳定且显著低于其它各时期；约从MIS 5d期开始表层初级生产力显著上升，并一直持续到末次冰期；在MIS1、2期，表层初级生产力有所下降，但仍高于MIS 6和MIS 5e期。 Ph05-5岩芯中钙质超微化石下透光带属种F. profunda相对百分含量和浮游有孔虫转换函数的温跃层深度变化表明西太平洋暖池北缘约190 kyr BP 以来，营养跃层和温跃层冰期（MIS 6期和5d~2期）浅，间冰期（MIS5e）和全新世深，MIS5e期是最近两个冰期旋回中营养跃层和温跃层深度最深的时期。F. profunda百分含量初级生产力转换方程计算结果和与钙质超微化石绝对丰度的变化显示冰期初级生产力高，间冰期和全新世初级生产力低， MIS5e期初级生产力最低。此外，Δδ13C C. wullerstorf-coccolith和Δδ13C C. wullerstorf-N. dutertrei差值的变化也说明190 kyr BP以来冰期表层输出生产力高于间冰期，其中最为突出的特征也是MIS5e期为生产力输出的最低值期。上层海水结构和生产力的上述变化特征与现代La Niňa事件爆发时的海洋环境相当类似，该海区MIS5e期可能是La Niňa事件频繁爆发的一段时期，可以与现代La Niňa现象类比。同时，根据Wyrtki提出的信风张弛理论推测MIS5e期，由于La Niňa事件的频繁爆发黑潮主流应该是增强的。 热带西太平洋暖池核心区WP7岩芯中250 kyr BP以来的初级生产力在间冰期明显低于冰期，间冰期生产力相对稳定，冰期(MIS6，4和2)生产力升降幅度较大；冰期向间冰期过渡的冰消期内生产力的降低是相对缓慢的，而间冰期向冰期过渡时生产力的增加是迅速的。初级生产力指标的交叉频谱分析显示出偏心率、斜率、岁差（半岁差）、30kyr和50kyr周期。说明暖池区晚第四纪以来古生产力变动除了受全球冰量变动控制以外，低纬区的岁差驱动也是主要控制因子。约250 kyr BP以来古生产力的变化与Vostok冰心的CO2记录在30kyr周期上高度相关，低CO2值与高生产力相对应，印证了大洋初级生产力在全球碳循环中扮演了重要的“吸收者”的角色，30kyr周期是赤道太平洋地区生物生产力ENSO式变化特征的体现，这也证明了低纬地区生物泵在控制大气CO2浓度方面的重要作用。另外，在岁差周期段，底栖有孔虫U+B含量和N. dutertrei δ13C代表的生产力变动领先于有孔虫δ18O代表的冰体积变化约2.6~7kyr（0.5kyr,2.6 kyr,4.2 kyr, 7kyr），表明在千年时间尺度上日射是该区生产力变化的直接驱动力，两极冰体积变化（δ18O）没有明显的影响低纬气候波动。 对热带西太平洋边缘海区WP7、Ph05-5、WP3和Z14-6四个岩芯中晚第四纪以来超微化石下透光带属种F. profunda相对百分含量变化进行横向对比研究表明，F. profunda百分含量分布并非简单受水深控制，而是由海水上层复杂的生态因素所决定；F. profunda相对百分含量变化曲线与浮游有孔虫N. dutertrei氧同位素曲线呈不同程度的相关性，N. dutertrei 氧同位素越轻，对应的F. profunda相对百分含量越高；冲绳海槽中部的Z14-6岩芯中F. profunda相对含量变化的主控因子是黑潮流的强弱变化；WP7和Ph05-5两个岩芯中F. profunda相对含量变化与低纬地区暖池变化特征密切相关。 6800 yr BP以来台湾东北部MD2908岩芯中F. profunda相对百分含量变化与太阳黑子数量呈明显的反相关关系，而且3700 yrBP以来更为明显。由于F. profunda相对百分含量变化与该地区东亚夏季风引起的降雨量密切相关，所以推测6800 yr BP以来东亚夏季风受太阳活动影响，其中的纽带是IZCT的纬向位置变动。

南海东部海盆的张裂特征及扩张方式研究

构造地貌分析，结合地震剖面和磁异常对比已成为研究年轻海底扩张机制和构造演化的重要手段。利用南海东部海盆首次获取的多波束高分辨率全覆盖数据，进行构造地貌特征分析，通过张裂特征断面研究、条带磁异常识别和构造应力场分析，提出了东部海盆的扩张方式和成因模式，重建了南海海盆新生代多期次、多方向扩张的构造演化历史。东部海盆存在三组走向不同的北东向线性构造带，自中脊海山链向南、北两侧对称分布于约350km宽的中央区内，是张性深大断裂、基底断块和线性火山基底隆起在海底的反映。这三组构造带分别对应海盆三个扩张期：条带磁异常6a-6c (24-21Ma)、5e-6a (21-19Ma)和5d-5e (5c) (19-16Ma)。东部海盆扩张方式具有不稳定性、脉动式、分段性及不对称的特点。各扩张期内，线性构造走向呈连续变化，而各扩张期之间线性构造走向则均有3°-5°跃变，反映扩张方向存在渐变和突变的演化特点；与扩张同期的北西向平移断裂表现为转换断层，空间分布上呈由东向西逐步加密的特征，各段间北东向线性构造走向变化较大，反映扩张轴纵向延伸的分段性和不稳定性；在21Ma（磁异常序列6a）前后，存在一次重要的海底扩张增速事件，增速幅度达40%，从早期的30.54 km/Ma增加到晚期的42.88 km/Ma，对应基底断裂、沉积作用和火山活动等张裂特征的跃变：扩张速率普遍东部大于西部、南侧明显大于北侧，导致海盆扩张具有东宽西窄的特点，具有较强的不对称性。东部海盆识别出的大量线性火山岩带平行于扩张轴，主要分布在火山基底隆起和基底断块边界断裂上，强度北侧大于南侧，是扩张过程中海底持续经受张裂作用的产物，说明海盆的北西-南东向扩张是受构造张裂型扩张机制的控制，具有大西洋慢扩张型的构造特征。据此并结合海盆扩张方式和构造、沉积特征所提出的东部海盆不对称构造扩张成因机制模式，很好地说明了中脊两侧张裂构造密度、岩浆活动强度和海底扩张方式的差异。这种代表慢速扩张的不对称构造成因机制在中脊附近较大范围内出现断块活动和基底拆离构造，并诱导岩浆沿断裂再次侵位和喷溢，从而在西南海盆因岩浆再侵位而使条带磁异常复杂化，在东部海盆因断裂、岩浆活动形成了一系列线性火山岩带和不规则沉积中心。南海海盆断面特征研究表明，南海海盆东部和西部具有不同的张裂机制，东部以海底扩张为主，西部以地壳减薄和裂离为主。东部在海底扩张的过程中，早期活动主要集中在南海海盆北部，晚期活动主要表现在黄岩海山链南北约350km范围内的中央区，而西部的裂离作用导致了中沙—西沙地块、南沙地块与北京大陆边缘的分裂和西南海盆海底扩张的形成。南沙地块进一步向南迁移最终在中中新世晚期与南巴拉望和沙巴—沙捞越地块碰撞、团结，从而结束了南海海盆的大规模扩张的历史。自32Ma以来，南海东部海盆主要经历三个构造演化阶段：32-27Ma期间的近南北向扩张，24-16Ma期间的北西—南东向扩张，并进一步可分为三个亚扩张期，以及中中新世（15Ma）后海盆沿北西西向马尼拉海沟的倾斜俯冲。

东海颗粒有机碳通量的模式计算

本研究论文属于国家科学基金重点研究项目“东海关键海洋通量过程的研究”计划的一个组成部分，通过1998年夏季东海航次，测定了颗粒有机碳的(Particulate Organic Carbon)含量，并研究了东海夏季POC含量的分布特点以及影响因素。同时，通过模式计算了部分站位的POC的垂直表观通量。然后，根据海水悬浮物质、底质物和浮游生物中的DOC的含量，定量的研究了东海的再悬浮现象，计算得到32°N断面和PN断面部分站位的再悬浮比，并计算得到了这些站位的POC净垂直通量，使我们对东海的POC净沉积通量有了一个定量的认识和把握。通过研究，我们发现东海夏季的POC的分布特点是：（1）近岸区域有明显的高值区的存在，并随离岸距离的增加而降低，这主要是受长江径流的影响；（2）在以(32°N, 125°E-125.5°E)为中心的冷涡表层海域存在着另一个POC含量的高值区，随深度增加而降低，在25米层以下随深度的增加而增加，在近底层形成一个新的高值区，研究表明表层高值区主要受生物生长的控制，而底层的高值区的存在与该区域的涡动层或上升流的存在有一定的关系；（3）同时，在东海所研究的两个断面，TSM（Total Suspended Materials）和POC的含量之间表现出了较好的相关性。通过模式研究，计算了六个站位八个层次的POC的垂直通量，其垂直通量为12.43 mg·m~(-2)·d~(-1)-148.23 mg·m~(-2)·d~(-1)，最大值为148.23 mg·m~(-2)·d~(-1)，出现在107站(32°N, 125°E)10米层，最小值为12.43 mg·m~(-2)·d~(-1)，出现在111站(32°0.08N, 125°59.57'E)的底层。通过对东海再悬浮比率的定量研究，计算了五个站和个层次的再悬浮比率。结果表明：（1）表层海水中悬浮物质的再悬浮比率在47.4%-79.18%之间；底层的再悬浮比率在72.75%-96.96%之间；（2）再悬浮比率的最大值出现在106站(32°N, 124°30'E)的底层，而再悬浮比率的最小值出现在102站(32°N, 122°30'E)的表层。在POC重直通量和再悬浮模式计算的基础上，我们计算得到了六个站位八个层次的POC净垂直通量，颗粒有机碳的净垂直通量最大值出现在107站(32°N, 125°E)的10米层，为117.4 mg·m~(-2)·day~(-1)；最小值出现在111站(32°0.08'N, 125°59.57'E)的底层为0.79 mg·m~(-2)·day~(-1)。通过几个站位的模式计算估算了东海颗粒有机碳平均的净沉积通量，其大约为6.55 mgC·m~(-2)·day~(-1)，即2.39gC·m~(-2)·y~(-1)。从而使我们对东海的颗粒有机碳的净垂直通量有了一个定量的认识。