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15-Methylcytosine RNA Methylation in Arabidopsis Thaliana显示文摘5-Methylcytosine (m 5 C ) 是描绘得好的 DNA 修正,并且主要也在初核质和优核质在丰富的非编码的 RNA 被报导。然而,分发和 m 5 在植物 mRNAs 的 C 仍然保持大部分未知。这里,我们报导 RNA m 5 在由使用 m 5 C RNA immunoprecipitation 由一条深定序的途径列在后面(m 5 C-RIP-seq ) 。LC-MS/MS 和点污点分析揭示 m 5 在各种各样的纸巾并且在不同发展阶段的 C mRNA 修正。m 5 C-RIP-seq 分析识别了 6045 m 5 在 4465 的 C 山峰在年轻幼苗表示了基因。我们发现那 m 5 C 在编码序列,二座山峰在开始 codons 以后并且在站 codons 前立即定位了被充实,并且随低翻译与 mRNAs 被联系活动。我们进一步表明了那 RNA (cytosine-5 )-methyltransferase,tRNA 特定的 methyltransferase 4B (TRM4B ) ,展览 m 5 C RNA methyltransferase 活动。在 TRM4B 的变化在根开发和减少的 m 5 C 山峰。TRM4B 影响涉及根开发的基因的抄本层次,它断然与他们的 mRNA 稳定性和 m 5 C 层次。我们的结果建议那 m 5 在 mRNA 的 C 是新 epitranscriptome 标记 inArabidopsis,并且这修正的那条规定是基因的不可分的部分规章的网络位于 \O 下面植物开发。Xuean Cui Zhe Liang Lisha Shen Qian Zhang Shengjie Bao Yuke Geng Bin Zhang Vonny Leo Leah A. Vardy Tiegang Lu Xiaofeng Gu Hao Yu 2017Molecular Plant2017,10,11:19
2N6-Methyladenine DNA Methylation in Japonica and Indica Rice Genomes and Its Association with Gene Expression,Plant Development, and Stress Responses显示文摘N6-Methyladenine (6mA)DNA methylation has recently been implicated as a potential new epigenetic marker in eukaryotes,including the dioot modelArabidopsis thaliana.However,the conservation and divergence of 6mA distribution patterns and functions in plants remain elusive.Here we report high-quality 6mA methylomes at single-nucleotide resolution in rice based on substantially improved genome sequences of two rice cultivars,Nipponbare (Nip;Japonica)and 93-11 (Indica).Analysis of 6mA genomic distribution and its association with transcription suggest that 6mA distribution and function is rather conserved between rice and Arabidopsis.We found that 6mA levels are positively correlated with the expression of key stressrelated genes,which may be responsible for the difference in stress tolerance between Nip and 93-11. Moreover,we showed that mutations in DDM1 cause defects in plant growth and decreased 6mA level. Our results reveal that 6mA is a conserved DNA modification that is positively associated with gene expression and contributes to key agronomic traits in plants.Qian Zhang Zhe Liang Xuean Cui Changmian Ji Yun Li Pingxian Zhang Jingrong Liu Adeel Riaz Pu Yao Min Liu Yunpeng Wang Tiegang Lu Hao Yu Donglei Yang Hongkun Zheng Xiaofeng Gu 2018Molecular Plant2018,11,12:18
3Evolution and variation of the Tsushima warm current during the late Quaternary: Evidence from planktonic foraminifera, oxygen and carbon isotopes显示文摘The evolution and variation history of the Tsushima warm current during the late Quaternary was reconstructed based on the quantitative census data of planktonic foraminiferal fauna, together with oxygen and carbon isotope records of mixed layer dweller G. ruber and thermocline dweller N. dutertrei in piston core CSH1 and core DGKS9603 collected separately from the Tsushima warm current and the Kuroshio dominated area. The result showed that the Tsushima warm current vanished in the lowstand period during 40―24 cal ka BP, while the Kuroshio still flowed across the Okinawa Trough, arousing strong upwelling in the northern Trough. Meanwhile, the influence of freshwater greatly increased in the northern Okinawa Trough, as the broad East China Sea continental shelf emerged. The freshwater reached its maximum during the last glacial maximum (LGM), when the upwelling obviously weakened for the lowest sea-level and the depression of the Kuroshio. The modern Tsushima warm current began its development since 16 cal ka BP, and the impact of the Kuroshio increased in the middle and north- ern Okinawa Trough synchronously during the deglaciation and gradually evolved as the main water source of the Tsushima current. The modern Tsushima current finally formed at about 8.5 cal ka BP, since then the circulation structure has been relatively stable. The water of the modern Tsushima cur- rent primarily came from the Kuroshio axis. A short-term wiggle of the current occurred at about 3 cal ka BP, probably for the influences from the enhancement of the winter monsoon and the depression of the Kuroshio. The cold water masses greatly strengthened during the wiggle.LI TieGang SUN RongTao ZHANG DeYu LIU ZhenXia LI Qing JIANG Bo 2007Science China Earth Sciences2007,50,5:15
4The RNA Editing Factor WSP1 Is Essentia for Chloroplast Development in Rice显示文摘尽管在 Arabidopsis thaliana 的质体编辑因素(MORF ) 的多重 organellar RNA 是位于下面 MORF 怎么在另外的种类影响植物开发的广泛地学习的、分子的细节,特别地在米饭,仍然保持大部分未知。这里,我们描述 wsp1 的描述,有白条纹的叶子和圆锥花序的米饭异种。尤其是, wsp1 在出发舞台展出了将近白的不成熟的圆锥花序。传播电子显微镜学分析和叶绿素内容测量揭示了叶绿体在 wsp1 的发展缺点和减少的叶绿素累积。在 Os04g51280 发现一个点变化的 WSP1 的位置的克隆,份额其通常认为的产品高与 MORF 蛋白质定序类似。互补实验证明 WSP1 为 wsp1 的使成杂色的显型负责。WSP1 对叶绿体局部性,在 wsp1 的点变化影响编辑多重 organellar RNA 地点。由于在编辑的质体 RNA 的缺点,叶绿体核糖体生物的续生说并且 ndhA 拼接也在 wsp1 被损害,它可以在出发阶段在叶子和圆锥花序影响正常叶绿体开发。一起,我们的结果在叶绿体开发表明米饭 WSP1 蛋白质的重要性并且在米饭关于 MORF 家庭成员拓宽我们的知识。Zhiguo Zhang Xuean Cui Yanwei Wang JinxiaWu Xiaofeng Gu Tiegang Lu 2017Molecular Plant2017,10,1:15
5The impact of cleats on hydraulic fracture initiation and propagation in coal seams显示文摘Cleats are systematic, natural fractures in coal seams. They account for most of the permeability and much of the porosity of coalbed methane reservoirs and can have a significant effect on the success of hydraulic fracturing stimulation. Laboratory hydraulic fracturing experiments were conducted on coal blocks under true tri-axial stress to simulate fracturing stimulation of coal seams. Fractures were initiated by injecting a water gel with luminous yellow fluorescent dye into an open hole section of a wellbore. The impact of cleats on initiation and propagation of hydraulic fractures in coal seams is discussed. Three types of hydraulic fracture initiation and propagation pattern were observed in this study: 1) The hydraulic fracture initiated and then grew along the cleat. 2) The hydraulic fracture initiated along a butt cleat or a fracture(natural or induced by drilling) oriented roughly in the minimum horizontal stress direction, then turned to propagate along the first face cleat that it encountered or gradually turned towards the maximum horizontal stress direction. 3) The hydraulic fracture initiated perpendicular to the minimum stress and, when it encountered a face cleat, tended to propagate along the cleats if the extension direction does not deviate greatly(<20° as determined in this paper) from the maximum horizontal stress direction. When a coal seam is hydraulically fractured, the resulting fracture network is controlled by the combined effect of several factors: cleats determine the initiation and extension path of the fracture, the in-situ stress state dominates the main direction of the fracture zone and bedding planes impede fracture height growth.Fan Tiegang Zhang Guangqing Cui Jinbang 2014Petroleum Science2014,11,4:14
6Quantitatively distinguishing sediments from the Yangtze River and the Yellow River using δEu_N-ΣREEs plot显示文摘Sediment samples were collected from the lower channel of the Yangtze River and the Yellow River and the contents of rare earth elements (REEs) were measured. In addition, some historical REEs data were collected from published literatures. Based on the δEuN-ΣREEs plot, a clear boundary was found be-tween the sediments from the two rivers. The boundary can be described as an orthogonal polynomial equation by ordinary linear regression with sediments from the Yangtze River located above the curve and sediments from the Yellow River located below the curve. To validate this method, the REEs con-tents of sediments collected from the estuaries of the Yangtze River and the Yellow River were meas-ured. In addition, the REEs data of sediment Core 255 from the Yangtze River and Core YA01 from the Yellow River were collected. Results show that the samples from the Yangtze River estuary and Core 255 almost are above the curve and most samples from the Yellow River estuary and Core YA01 are below the curve in the δEuN-ΣREEs plot. The plot and the regression equation can be used to distin-guish sediments from the Yangtze River and the Yellow River intuitively and quantitatively, and to trace the sediment provenance of the eastern seas of China. The difference between the sediments from two rivers in the δEuN-ΣREEs plot is caused by different mineral compositions and regional climate patterns of the source areas. The relationship between δEuN and ΣREEs is changed little during the transport from the source area to the river, and from river to the sea. Thus the original information on mineral compositions and climate of the source area was preserved.JIANG FuQing ZHOU XiaoJing LI AnChun LI TieGang 2009Science China Earth Sciences2009,52,2:14
7Impacts of water release operations on algal blooms in a tributary bay of Three Gorges Reservoir显示文摘Water release operation is crucial for water quality in large reservoirs such as Three Gorges Reservoir(TGR),because it determines the hydrodynamics and hence the self-purification capability.As algal blooms were often observed in some tributary bays of TGR during the release periods,high frequency field observations were carried out in a typical eutrophic tributary bay(Xiangxi River) from February 9 to May 10,2009.In this paper we assess the hydrodynamic behaviour,density stratification,and trophic status in this bay,respectively using a series of observations for flow,physical,chemical and biological parameters.Then,we analyze the effects of reservoir release operations on algal blooms using correlation analysis method.An empirical prognosis is concluded for the likelihood of algal bloom occurrence as a function of daily fluctuation of water level(DFWL) and water temperature.Our results indicate that during the release period,the algal bloom occurrences are closely tied to the DFWL in that if the ratio of DFWL to total water depth ranges from -10×10-4 to 0,the possibility of algal blooms may reach up to 70%,and if the ratio is less than -10×10-4,then that risk can be significantly reduced to less than 10%.This paper finally suggests that a wave-type water release operation should be beneficial in reducing bloom frequencies in the tributary water bodies,which is helpful for TGR water quality management,especially for the water release operation optimization.ZHENG TieGang MAO JingQiao DAI HuiChao LIU DeFu 2011Science China(Technological Sciences)2011,54,6:12
8Geochemistry of rare earth elements in the mid-late Quaternary sediments of the western Philippine Sea and their paleoenvironmental significance显示文摘Based on a δ18O chronology,rare earth elements(REE) and other typical elements in sediments from core MD06-3047 in the western Philippine Sea were analyzed to constrain the provenances of the sediments and investigate quantitative changes in the Asian eolian input to the study area over the last 700 ka.Among the competing processes that might affect REE compositions,sediment provenance is the most important one.Provenance analysis suggests that the study sediments have two provenance end-members;local volcanic sources are dominant,and eolian dust from the Asian continent has a smaller contribution.During glacial periods,eolian input to the western Philippine Sea was enhanced.In contrast,material supply from local volcanics increased during interglacial periods.Changes in eolian input to the study area were probably related to the strength of the East Asian winter monsoon(EAWM) as well as aridity in the Asian continent on an orbital time scale,and were partly influenced by local control factors on shorter time scales.Therefore,we propose that the present study expands the application of the REE-based method for quantitatively estimating the eolian component from the mid-latitude northern Pacific to the low-latitude western Pacific.Additionally,the study preliminarily confirms the influence of EAWM-transported eolian material on sedimentation in the western Philippine Sea since 700 ka.XU ZhaoKai LI TieGang WAN ShiMing YIN XueBo JIANG FuQing SUN HanJie JinYong CHOI DhongIl LIM 2014Science China Earth Sciences2014,57,4:10
9Mechanical,Microstructural and Tribological Properties of Reactive Magnetron Sputtered Cr-Mo-N Films显示文摘The Cr-Mo-N films were deposited on high speed steel(HSS) substrates by a DC reactive magnetron sputtering equipment coupled with two horizontal magnetron sources.The effects of substrate negative bias voltage(V_b),substrate temperature(T_s) and gas flow ratio(R= N_2/(N_2 + Ar)) on the microstructure,morphology,as well as the mechanical and tribological properties of the Cr-Mo-N films were investigated by virtue of X-ray diffraction(XRD) analysis,X-ray photoelectron spectroscopy(XPS),field emission scanning electron microscopy(FESEM),atomic force microscopy(AFM),nano-indentation test,ball-on-disk tribometer,and Rockwell indenter et al.With increasing V_b to-100 V,the preferred orientation of the films changed from(111) to(200) and their mechanical and tribological properties were improved gradually,too.It was also found that T_s gave a significant effect on mechanical property enhancement.When the T_s reached 300 ℃,the film obtained the highest hardness and effective elastic modulus of approximately 30.1 and 420.5 GPa,respectively and its critical load increased to about 54 N.With increasing R,the phase transformation from body-centered-cubic(bcc) Cr and hexagonal CrMoN_x multiphase to single face-centered-cubic(fcc) solid solution phase was observed.The correlations between values of hardness(H),effective elastic modulus(E~*),HIE~*,H^3/E^(*2),elastic recovery(1/14) and tribological properties of the films were also investigated.The results showed that the elastic recovery played an important role in the tribological behavior.Dongli Qi Hao Lei Tiegang Wang Zhiliang Pei Jun Gong Chao Sun 2015Journal of Materials Science & Technology2015,31,1:10
10Vast laminated diatom mat deposits from the west low-latitude Pacific Ocean in the last glacial period显示文摘Diatoms are one of the predominant contributors to global carbon fixation by accounting for over 40% of total oceanic primary production and dominate export production. They play a significant role in marine biogeochemistry cycle. The diatom mat deposits are results of vast diatoms bloom. By analysis of diatom mats in 136°00′―140°00′E,15°00′―21°00′N, Eastern Philippines Sea, we identified the species of the diatoms as giant Ethmodiscus rex (Wallich) Hendey. AMS 14C dating shows that the sediments rich in diatom mats occurred during 16000―28600 a B.P., which means the bloom mainly occurred during the last glacial period, while there are no diatom mat deposits in other layers. Preliminary analysis indicates that Antarctic Intermediate Water (AAIW) expanded northward and brought silicate-rich water into the area, namely, silicon leakage processes caused the bloom of diatoms. In addition, the increase of iron input is one of the main reasons for the diatom bloom.ZHAI Bin LI TieGang CHANG FengMing CAO QiYuan 2009Chinese Science Bulletin2009,54,23:9
11Benthic foraminifera and bottom water evolution in themiddle-southern Okinawa Trough during the last 18 ka显示文摘A piston sediment core E017 from the middle-southern Okinawa Trough was investigated. A preliminary study of the deep-water evolution since 18 cal. ka BP was performed basedon the quantitative census data of benthic foraminiferal fauna, together with planktonic foraminiferal oxygen and carbon isotope, AMS14C dating, and the previous results achieved in thesouthern Okinawa Trough. The result shows that the benthic fauna was dominated by Buliminaaculeata (d′Orbigny), Uvigerina peregrina (Cushman), Hispid Uvigerina and Uvigerina dirupta(Todd) during the glaciation-deglaciation before 9.2 cal. ka BP, while Epistominella exigua(Brady), Pullenia bulloides (d′Orbigny), Cibicidoides hyalina (Hofker), Sphaeroidina bulloides(d’Orbigny) and Globocassidulina subglobosa (Brady) predominated the fauna in the post-glaciaperiod after 9.2 cal. ka BP. The benthic foraminifera accumulation rate (BFAR), paleoproductivityestimates and benthic foraminiferal assemblage conformably indicate that surface water paleoproductivity and organic matter flux during the glaciation-deglaciation were higher than those othe post-glacial period in the middle-southern Okinawa Trough, and gradually enhanced from thesouthern to the central Okinawa Trough during the glaciation-deglaciation, which could becaused by the discrepancy of the terrigenous nutrients supply. High abundances of E. exigua, anindicator of pulsed organic matter input, after 9.2 cal. ka BP may indicate that the intensity oseasonally riverine pulsed flux during the post-glacial period was stronger than that of the glaciation-deglaciation period, and the seasonal influx in the central trough might be stronger than inthe south. The temporal distributions of the typical species indicating bottom water oxygen content and ventilation condition show that the ventilation of the bottom water during the post-glaciaperiod is more active than the glaciation-deglaciation, which reflects that the evolution of the intermediate and deep waters of the northwestern Pacific during the last glaciation has no evideninfluence on the deep-water of the middle-southern Okinawa Trough. Additionally, the variationsin agglutinated benthic foraminiferal abundance and other carbonate dissolution proxies indicatethat carbonate dissolution gradually increased since the last 18 ka in the Okinawa Trough andrapidly enhanced at 9.2 cal. ka BP. The modern shallow carbonate lysocline could form at 3 calka BP.LI Tiegang1, XIANG Rong1,2, SUN Rongtao1 & CAO Qiyuan1 1. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China 2. College of Geosciences, Ocean University of China, Qingdao 266003, China Correspondence should be addressed to Li Tiegang 2005Science China Earth Sciences2005,48,6:9
12Testing the mantle plume hypothesis: an IODP effort to drill into the Kamchatka-Okhotsk Sea basement显示文摘The great mantle plume debate(GPD) has been going on for ~15 years(Foulger and Natland, 2003;Anderson, 2004; Niu, 2005; Davies, 2005; Foulger, 2005; Campbell, 2005; Campbell and Davies, 2006),centered on whether mantle plumes exist as a result of Earth's cooling or whether their existence is purely required for convenience in explaining certain Earth phenomena(Niu, 2005). Despite the mounting evidence that many of the so-called plumes may be localized melting anomalies, the debate is likely to continue. We recognize that the slow progress of the debate results from communication difficulties.Many debaters may not truly appreciate(1) what the mantle plume hypothesis actually is, and(2) none of the petrological, geochemical and geophysical methods widely used can actually provide smoking-gun evidence for or against mantle plume hypothesis. In this short paper, we clarify these issues, and elaborate a geologically effective approach to test the hypothesis. According to the mantle plume hypothesis, a thermal mantle plume must originate from the thermal boundary layer at the core-mantle boundary(CMB), and a large mantle plume head is required to carry the material from the deep mantle to the surface. The plume head product in ocean basins is the oceanic plateau, which is a lithospheric terrane that is large(1000's km across), thick(>200 km), shallow(2–4 km high above the surrounding seafloors), buoyant(~1% less dense than the surrounding lithosphere), and thus must be preserved in the surface geology(Niu et al., 2003). The Hawaiian volcanism has been considered as the surface expression of a type mantle plume, but it does not seem to have a(known) plume head product. If this is true, the Hawaiian mantle plume in particular and the mantle plume hypothesis in general must be questioned. Therefore, whether there is an oceanic plateau-like product for the Hawaiian volcanism is key to testing the mantle plume hypothesis, and the Kamchatka-Okhotsk Sea basement is the best candidate to find out if it is indeed the Hawaiian mantle plume head product or not(Niu et al., 2003; Niu, 2004).Yaoling Niu Xuefa Shi Tiegang Li Shiguo Wu Weidong Sun Rixiang Zhu 2017Science Bulletin2017,62,21:8
13Late Holocene paleoenvironmental changes in the southern Okinawa Trough inferred from a diatom record显示文摘We analyzed sediment diatoms from core MD05-2908 to infer climate and paleoenvironmental changes in the southern Okinawa Trough (SOT) over the past 1000 years.Because the study area is located in the East Asia monsoon area and beneath the main axis of Kuroshio Current,the climatic and hydrographical conditions are strongly influenced by both of these factors.The species used as environmental indicators,including the Kuroshio Current species (KC species) and freshwater species,were investigated in this paper.Changes in the abundance of the two groups of species revealed significant variations in water temperature and hydrography in the SOT during the Medieval Warm Period (MWP) and the Little Ice Age (LIA).From 950-1500 AD,the abundance of the KC species increased fluctuantly,while the freshwater species decreased,showing that the influence of the Kuroshio Current was intensified at that interval and the precipitation of the study area was relatively low.The KC species decreased remarkably and was maintained at a low abundance during the interval of 1500-1900 AD,which suggests that the impact of the Kuroshio Current on the SOT weakened during the period corresponding to the LIA.Moreover,the high abundance of the freshwater species at the same interval indicates a distinct increase in precipitation in northeastern Taiwan,which may be correlated to the south-detention of the rainfall belt in China caused by the southward migration of the western Pacific subtropical high.LI DongLing JIANG Hui LI TieGang ZHAO MeiXun 2011Chinese Science Bulletin2011,56,11:8
14A broad deglacial δ^(13)C minimum event in planktonic foraminiferal records in the Okinawa Trough显示文摘The equatorial Pacific upwelling zone has been suspected of playing an important role in the global atmospheric CO2 changes associated with glacial-interglacial cycles. In order to assess the influencing scope of the surface water deglacial δ13C minimum in the tropical low-latitude Pacific, the core DGKS9603, collected from the middle Okinawa Trough, was examined for δ13C records of planktonic fo-raminifera N. dutertrei and G. ruber. The planktonic fo-raminiferal δ13C records show a clear decreasing event from 20 to 6 cal. kaBP., which is characterized by long duration of about 14 ka and amplitude shift of 0.4×10-3. Its minimum value occurred at 15.7 cal kaBP. The event shows fairly synchrony with the surface water deglacial δ13C minimum identified in the tropical Pacific and its marginal seas. Because there is no evidence in planktonic foraminiferal fauna and δ18O records for upwelling and river runoff enhancement, the broad deglacial δ13C minimum event in planktonic foraminiferal recordsLI Tiegang, LIU Zhenxia, M. A. Hall, Y. Saito, S. Berne, GANG Shuxi & CHENG ZhenboInstitute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China The First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China Godwin I 2002Chinese Science Bulletin2002,47,7:7
15Sediment provenance and evolution of the East Asian winter monsoon since 700 ka recorded by major elements in the West Philippine Sea显示文摘To synthetically realize the character of major-element compositions as well as its significance for provenance and paleoenvironment recorded in core sediments of the West Philippine Sea over the last 700 ka,grain size and major elements of 221 bulk sediments,together with major-element compositions in the detrital phase of 16 typical samples,in core MD06-3047 collected from the Benham Rise were analyzed.Both discrimination plot and R-mode factor analysis indicate that vertical changes of major elements are mainly controlled by the sedimentation of nearby volcanic matter and the eolian dust input,whereas influences from marine biologic deposition and hydrothermal activity are minor.In particular,Al2O3 and K2O are representative of an eolian dust factor.The variation in the eolian dust factor score is characterized by the obviously glacial-interglacial periodicity and can be well compared with the paleotemperature record of the Antarctic ice core and the evolution of the East Asian winter monsoon(EAWM) recorded in the Chinese loess sequence,and then offers a new proxy for the evolution history of eolian dust input into the study area that is controlled by the EAWM intensity and aridity in the continental source regions of atmospheric dust.XU ZhaoKai LI TieGang YU XinKe LI AnChun TANG Zheng CHOI JinYong NAN QingYun 2013Chinese Science Bulletin2013,58,9:7
16Development of performance and combustion system of Atkinson cycle internal combustion engine显示文摘The application of hybrid vehicle is a practical technical solution to the energy shortage and the environmental pollution.The internal combustion engine(ICE)plays a key role in the development of the hybrid vehicle.Based on the requirements of the hybrid vehicle and the characteristic of Atkinson cycle,a set of designing methods for the Atkinson cycle gasoline engine is presented through the analysis of the optimized matching for the compression ratio,valve timing and the combustion chamber.The designing method has been verified by the bench test and the results show that the fuel consumption can be improved by12%–15%with the reduction of the low speed torque by 10%,and the low fuel consumption region in the fuel map extends significantly with the rated power almost keeping constant.It may be of great reference for the development of hybrid vehicle technology in China.LIU FuShui SUN BaiGang ZHU HuaRong HU TieGang DU Wei LI XiangRong ZHANG Zheng 2014Science China(Technological Sciences)2014,57,3:7
17Sedimentation rates and provenance analysis in the Southwestern Okinawa Trough since the mid-Holocene显示文摘As a high-sedimentation rate depocenter along the path of the Kuroshio Current, the southwesternmost part of the Okinawa Trough is a key area to understand the Kuroshio history and sediments transpor-tation. A 34.17-m-long sediment core was obtained by the advanced piston corer of Marco Polo/IMAGES XII MARION DUFRESNE during the May 2005 from the Southern Okinawa Trough at site MD05-2908. The recovered sediments were analyzed by AMS 14C dating, coarse size fraction (>63 μm) extraction and moisture content determination in order to study its sedimentation flux and provenance. The depth-age relationship of core MD05-2908 was well constrained by 17 14C dating points. The sediments span across the mid-Holocene (6.8 ka B.P.) and have remarkablely high sedimentation rates between 1.8 and 21.2 m ka?1, which is well consistent with the modern observations from sediment traps. We identified five 70―200 a periods of abnormally rapid sedimentation events at 6790―6600 a B.P., 5690―5600 a B.P., 4820―4720 a B.P., 1090―880 a B.P., and 260―190 a B.P., during which the highest sedimentation rate is up to 21.2 m/ka. In general, the lithology of the sediments were dominated by silt and clay, associated with less than 5% coarse size fraction (>63 μm). As the most significant sediment source, the Lanyang River in northeastern Taiwan annually deliver about 10Mt materials to the coastal and offshore region of northeast Taiwan, a portion of which could be carried northward by currents toward the study area. Therefore, we concluded that the 5 abnormally rapid sedimentation events may be related to intensified rainfall in Taiwan and thus increased materials to our study area at that time. However, a few extreme-rapid sedimentation events cannot be explained by normal river runoff alone. The large earth-quakes or typhoons induced hyperpycnal discharge of fluvial sediment to the ocean may also act as a potential source supply to the Okinawa Trough.LI ChuanShun JIANG Bo LI AnChun LI TieGang JIANG FuQing 2009Chinese Science Bulletin2009,54,7:7
18Effects of Cr interlayer on mechanical and tribological properties of Cr-Al-Si-N nanocomposite coating显示文摘Cr-Al-Si-N coatings were deposited on SUS 304 substrate by a hybrid coating system. A Cr interlayer was introduced between Cr-Al-Si-N coating and SUS 304 substrate to improve the coating adherence. The effects of Cr interlayer on the microhardness, adhesion, and tribological behavior of Cr-Al-Si-N coatings were systematically investigated. The results indicate that the microhardness of the Cr-Al-Si-N coatings gradually deceases with increasing thickness of Cr interlayers. The adhesion between Cr-Al-Si-N and SUS 304 substrate is improved by addition of the Cr interlayers. A peak critical load of ~50 N is observed for the coating containing Cr interlayer of 60 nm as compared ~ 20 N for the coating without Cr interlayer. The thicker Cr interlayers result in reduced critical load values. Moreover, the wear resistance of the Cr-Al-Si-N coatings is greatly enhanced by introducing the Cr interlayer with thickness of 60 nm in spite of the decreased microhardness. The friction coefficient of the coating system is also moderately reduced.Young Su HONG Se Hun KWON Tiegang WANG Doo-In KIM Jihwan CHOI Kwang Ho KIM 2011Transactions of Nonferrous Metals Society of China2011,21,A01:6
19Association between dietary habits and recurrent respiratory infection in children: A case-control study显示文摘Objective:To explore the association between dietary habits and recurrent respiratory infection(RRI)in children aged 0e14 years.Methods:This caseecontrol study compared dietary data of children with(cases)and without RRI(controls)collected via structured questionnaire.Participants were recruited from Chinese medicine clinics,hospitals,and children’s learning institutions in Beijing.A logistic regression analysis and odds ratio(OR)calculations were conducted using SPSS 17.0 software.Results:A total of 241 questionnaires were collected(case:control ratio:approximately 2:1).Frequent consumption of processed foods(OR Z 2.988,95%confidence intervals 1.375e6.491)and high-sugar foods(OR Z 2.268,95%confidence intervals 1.163e4.424),frequent picky eating(OR Z 2.614,95%confidence intervals 1.363e5.014),and a meat-heavy diet with fewer vegetables(OR Z 1.830,95%confidence intervals 1.358e2.467)correlated positively correlated with RRI.Additionally,57.80%of the children with RRI were addicted to high-sugar foods,compared with 41.57%of the children without RRI(P Z.015).Furthermore,63.16%of the children with RRI were picky eaters,compared with 48.31%of the children without RRI(P Z.024).Finally,30.92%of the children with RRI frequently consumed processed foods,compared with only 17.98%of the children without RRI(P Z.027Conclusion:Although RRI correlates positively with several dietary habits,in the future,prospective cohort studies with larger samples are needed to generalize these findings.Wang Zhang He Yu Jinbang Shang Tiegang Liu Jiaju Ma Xiaohong Gu 2015Journal of Traditional Chinese Medical Sciences2015,2,2:5
20Response of the northwestern Pacific upper water δ^(13)C to the last deglacial ventilation of the deep Southern Ocean显示文摘The deglacial δ~13C minimum events that originated from the ventilation of the deep Southern Ocean around Antarctica, have been recorded in a range of marine sediments from the southern to tropical oceans in late Pleistocene. However, the broad δ~13C minimum event was also reported as far as to the northern middle latitudes, in northwestern Pacific marginal sea areas, during the last deglaciation. In the northwestern Pacific, forcing from the northern high latitudes is strongly expressed, while the records of in- fluence from the southern high latitudes are few. The Kuroshio Source Region (KSR) forms a boundary between the northwestern Pacific and the southern, tropical Pacific. So, high-resolution planktonic foraminiferal records in core MD06-3054 from the KSR are well positioned to identify signals from the southern hemisphere in the northwestern Pacific. Planktonic foraminiferal tests from the upper 1030 cm of the core were subject to AMS14C, carbon and oxygen isotopic measurements. A negative excursion was found to occur from about 20.0-6.0 ka BP in δ~13C records of both surface (Globigerinoides ruber) and subsurface (Pulleni- atina obliquiloculata) dwellers, but the overall trends of the two curves have reversed since 26.5 ka BP. Moreover, the δ~13C rec- ord of G. ruber (the surface dweller) shows a robust link to the record of atmospheric CO2, and its changes precede the records of P. obliquiloculata (the subsurface dweller). According to the hydrologic conditions, the broad δ~13C minimum event recorded in the KSR is also a response to the increasing ventilation of the deep Southern Ocean around Antarctica during the last deglaciation. The inconsistency between the records of the surface and subsurface dwellers was possibly caused by the ways that the low δ~13C signal was transmitted. Subsurface water primarily received the low δ~13C signal from the Antarctic Intermediate Water (AAIW), whereas the surface water was probably mainly impacted by atmospheric CO2 in the KSR. The records from the KSR confirm the deduction that the broad δ~13C minimum event in the Okinawa Trough was due to the impact of tropical Pacific surface water dur- ing the last deglaciation, and suggest that signals from the southern high latitudes also can be delivered to the northern middle latitudes.CHEN ShuangXi LI TieGang TANG Zheng QIU XiaoHua XIONG ZhiFang NAN QingYun XU ZhaoKai CHANG FengMing 2011Chinese Science Bulletin2011,56,24:5
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