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1Onset of the Kwangsian Orogeny as evidenced by biofacies and lithofacies显示文摘The onset timing of the Kwangsian Orogeny might differ among localities across South China.Refined stratigraphic works at different localities are necessary to reveal the details of this likely distinction.Recently,we recollected some graptolite specimens from the Ordovician Shixing and Longtouzhai formations(corresponding to the Longxi Formation of southern Jiangxi Province) at many localities in Guangdong Province.The palaeontological and biostratigraphical studies of these graptolite faunas indicate that the facies change from graptolitic shale to nearshore shallow-water,coarse clastics in Guangdong is slightly earlier than that in southern Jiangxi.This timing difference may imply a northward progression of the Kwangsian Orogeny.Based on the biostratigraphy and palaeontology of the Ordovician in the Zhujiang Basin(western part) and Chiangnan Slope Belt(including western Fujian,eastern Guangdong,northern Guangxi,northern Hunan,northeastern Jiangxi,southern Anhui,and western Zhejiang),the Sandbian to late Katian distribution and replacement of biofacies and lithofacies in the two regions are proposed and discussed,which display distinct features at different stages of the Kwangsian Orogeny.CHEN Xu ZHANG YuanDong FAN JunXuan TANG Lan SUN HaiQing 2012Science China Earth Sciences2012,55,10:31
2Ordovician graptolite-bearing strata in southern Jiangxi with a special reference to the Kwangsian Orogeny显示文摘The Ordovician graptolite sequence of the Yongxin-Chongyi area in southern Jiangxi was suggested as a standard for the correlation of Ordovician in the Zhujiang region of South China. Based on a restudy of the Upper Ordovician graptolites, the Shikou and Huamianlong formations are recognized herein as a part of the Hanjiang Formation, corresponding only to the Dipla-canthograptus caudatus-Diplacanthograptus spiniferus Zone. Two graptolite zones in the Longxi Formation of Yongxin and Chongyi, the Nemagraptus gracilis Zone and Climacograptus bicornis Zone, are redefined here. A rapid replacement of facies from the typical deep-water graptolitic black shale of Longxi Formation to the rapidly-accumulated, shallow-water clastic deposits of Hanjiang Formation indicates the tectonic initiation of the Kwangsian Orogeny. The thick clastic deposits of the Han-jiang Formation are proposed to come from a nearby source area that rose during the Kwangsian Orogeny. The D. caudatus-D. spiniferus graptolite Zone of the Hanjiang Formation indicates the initiation time of this tectonic event.Xu Chen YuanDong Zhang JunXuan Fan JunFeng Cheng QiJian Li 2010Science China Earth Sciences2010,53,11:29
3Changes of net primary productivity in China during recent 11 years detected using an ecological model driven by MODIS data显示文摘网主要生产率(NPP ) 是陆上的碳周期的一个重要部件。精确地在中国印射 NPP 的空间时间的变化为全球碳骑车是关键的学习。在这研究,基于过程的北方的生态系统生产率模拟器(BEPS ) 被采用从 2000 ~ 2010 为时期在中国的生态系统学习 NPP 的变化。BEPS 模型首先用在在不同区域测量的典型流动地点和森林 NPP 测量的粗野主要生产率(GPP ) 被验证。然后,它与叶区域索引( LAI )被驾驶从中等分辨率成像分光辐射函数( MODIS )反射和陆地盖子产品和气象学的数据的 inversed 在 753 个国家基本气象学的车站从观察插入内推从1月1日在每日的时间步和 500 m 的空间分辨率模仿 NPP , 2000 到2010年12月31日。确认证明 BEPS 能在中国的不同区域捕获基于塔的 GPP 的季节的变化和森林 NPP 的空间可变性。年度 NPP 的估计的国家总数从 2.63 变化了到 2.84Pg C 獥吗?Yibo LIU Weimin JU Honglin HE Shaoqiang WANG Rui SUN Yuandong ZHANG 2013Frontiers of Earth Science2013,7,1:30
4Recent progress of surface coating on cathode materials for high-performance lithium-ion batteries显示文摘Lithium-ion batteries (LIB) have received substantial attention in the last 10 years,as they offer great promise as power sources that can lead to the electric vehicle (EV) revolution in the next 5 years.Since the cathode serves as a key component in LIB,its properties significantly affect the performance of the whole system.Recently,the cathode surface modification based on coating technique has been widely employed to enhance the electrochemical performances by improving the material conductivity,stabilising the physical structure of materials,as well as preventing the reactions between the electrode and electrolyte.In this work,we reviewed the present of a number of promising cathode materials for Li-ion batteries.After that,we summarized the very recent research progress focusing on the surface coating strategies,mainly including the coating materials,the coating technologies,as well as the corresponding working mechanisms for cathodes.At last,the challenges faced and future guidelines for optimizing cathode materials are discussed.In this study,we propose that the structure of cathode is a crucial factor during the selection of coating materials and technologies.Peiyuan Guan Lu Zhou Zhenlu Yu Yuandong Sun Yunjian Liu Feixiang Wu Yifeng Jiang Dewei Chu 2020Journal of Energy Chemistry2020,29,4:28
5Biostratigraphy and geography of the Ordovician-Silurian Lungmachi black shales in South China显示文摘Based on the new material of seven Ordovician-Silurian boundary sections investigated recently, together with previously published data, we analyze the temporal and spatial distributions of the Lungmachi black shales, a key petroleum source bed widely distributed in South China. The Lungmachi black shales range in age from the Normalograptus persculptus Biozone of the uppermost Ordovician to the Spirograptus guerichi Biozone of the lower Telychian, and ten graptolite biozones can be recognized within this unit. The basal and upper contacts of the Lungmachi black shales are diachronous. The basal contact ranges from the N. persculptus to the C. cyphus biozones, a span of five graptolite biozones over two stages. The upper contact ranges from the D. pectinatus-M. argenteus Biozone to the Spirograptus guerichi Biozone, which spans four graptolite biozones over two stages. The Yichang Uplift resulted in the formation of the Hunan-Hubei Submarine High in the border area of Hubei, Hunan, and Chongqing. This is supported by a break in sedimentation in this area spanning all or part of the Hirnantian, and in many areas extending into the underlying Katian and overlying Rhuddanian. Comparison of the distribution of the Katian to Rhuddanian strata in this area indicates a growth and subsequent reduction in area of the Hunan-Hubei Submarine High particularly in the Hirnantian to early Rhuddanian. This may partly represent the influence of the process of formation and melting of ice sheet in Ordovician South Pole and consequent sea level change.FAN JunXuan Michael J MELCHIN CHEN Xu WANG Yi ZHANG YuanDong CHEN Qing CHI ZhaoLi CHEN Feng 2011Science China Earth Sciences2011,54,12:24
6Establishment of the diploid gynogenetic hybrid clonal line of red crucian carp × common carp显示文摘This study investigated the gynogenetic cytobiological behavior of the third gynogenetic generation (G3), which was generated from the diploid eggs produced by the second gynogenetic generation (G2) of red crucian carp × common carp, and determined the chromosomal numbers of G3, G2×scatter scale carp and G2×allotetraploid hybrids of red crucian carp × common carp. The results showed that the diploid eggs of G2 with 100 chromosomes, activated by UV-irradiated sperm from scatter scale carp and without the treatment for doubling the chromosomes, could develop into G3 with 100 chromosomes. Similar to the first and second gynogenetic generations (G1 and G2), G3 was also diploid (2n=100) and presented the hybrid traits. The triploids (3n=150) and tetraploids (4n=200) were produced by crossing G2 with scatter scale carp and crossing G2 with allotetraploids, respectively. The extrusion of the second polar body in the eggs of G2 ruled out the possibility that the retention of the second polar body led to the formation of the diploid eggs. In addition, we discussed the mechanism of the formation of the diploid eggs generated by G2. The establishment of the diploid gynogenesis clonal line (G1, G2 and G3) provided the evidence that the diploid eggs were able to develop into a new diploid hybrid clonal line by gynogenesis. By producing the diploid eggs as a unique reproductive way, the diploid gyno- genetic progeny of allotetraploid hybrids of red crucian carp × common carp had important signifi- cances in both biological evolution and production application.LIU ShaoJun, DUAN Wei, TAO Min, ZHANG Chun, SUN YuanDong, SHEN JiaMin, WANG Jing, LUO KaiKun & LIU Yun Key Laboratory of Protein Chemistry and Fish Developmental Biology of Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha 410081, China 2007Science China(Life Sciences)2007,50,2:21
7Spatial-temporal Characteristics of Land Use Intensity of Coastal Zone in China During 2000–2010显示文摘Based on remote sensing and GIS techniques, land use maps in 2000, 2005 and 2010 in China′s coastal zone were produced, and structural raster data of land use were further generated to calculate land use intensity comprehensive index(LUICI) for analyzing land use spatial-temporal characteristics at 1 km scale. Results show that: 1) from the perspective of spatial patterns of landforms at a macro scale, there is a significant difference in land use intensity between the north and the south of China′s coastal zone. Hotspots of changes mainly concentrated in metropolitan areas, estuaries and coastal wetlands; 2) elevation is an important factor that controlling land use spatial patterns at local scale. Land use intensity is much higher within areas below the elevation of 400 m and it decreased significantly as the elevation increasing; 3) there is a significant land-ocean gradient for land use intensity, which is low in island and near-shore areas, but high in the regions that 4–30 km far away the coastline because of much intensive human activities; however, in recent decades land use intensity had been promoted significantly in low near-shore area due to extensive sea reclamations; 4) significant differences of land use intensity were also found among provincial administrative units. A rising trend of land use intensity was found in provincial-level administrative units from 2000 to 2010. To sum up, elevation, land-ocean gradient, socio-economic status and policy are all influencing factors to the spatial patterns and temporal variations of land use intensity in China′s coastal zone.DI Xianghong HOU Xiyong WANG Yuandong WU Li 2015Chinese Geographical Science2015,25,1:20
8Characteristics of coastline changes in China's Mainland since the early 1940s显示文摘Based on multi-temporal topographic maps, remote sensing images and field surveys covering the entire coastal zone of China's Mainland, the coastlines of six periods since the early 1940 s were extracted. Coastline changes over the last 70 years were then analyzed in terms of coastline structure, coastline fractals, coastline change rates, land-sea patterns, and bay areas. The results showed that mainland coastline structure changed dramatically, and due to the significant coastline artificialization mainly driven by sea reclamation and coastal engineering, the remaining natural coastline merely accounts for less than one third at present. Coastline fractal dimension represented an overall spatial pattern of 'north < entirety < south'; however, the discrepancy between the north and south coast was apparently narrowed due to dramatic coastline artificialization of northern China which in turn altered the whole pattern. Patterns and processes of land-sea interchange along the mainland coast were complex and varied spatially and temporally, with over 68% advancing toward sea and 22% retreating toward land. The net growth of land area was nearly 14.2 ×103 km2 with an average growth rate of 202.82 km2 a??; and coast retreat was characterized by area decrease of 93 bays with a magnitude of 10.1 ×103 km2 and an average shrinking rate up to 18.19% or an average shrinking speed up to 144.20 km2 a??, among which the total area of Bohai shrunk by 7.06%, with an average annual loss amounting to 82 km2. The dramatic coastline changes along China's Mainland have brought about kinds of challenges to the coastal environment, therefore the integrated management, effective environment protection and sustainable utilization of coastlines is urgent.HOU XiYong WU Ting HOU Wan CHEN Qing WANG YuanDong YU LiangJu 2016Science China Earth Sciences2016,59,9:18
9The Central Guizhou and Yi-chang uplifts, Upper Yangtze region,between Ordovician and Silurian显示文摘The Central Guizhou and Yichang Uplifts are present in central Guizhou to western Hubei. Biostrati-graphic evidences from more than 20 sections in 14 counties of this region provide the data about the duration of these uplifts. Although this duration differs from locality to locality, it is mainly from Ashgillian to Rhuddanian. The uplifts result from a horizontally driven movement to the South China Paleoplate from an uncertain block in southeast. Global sea-level drop during the end of the Ordovician made the uplifts obvious, particularly the Central Guizhou Uplift.It might have emerged above sea level in the short interval between the Ordovician and Silurian.CHEN Xu RONG Jiayu ZHOU Zhiyi ZHANG Yuandong ZHAN Renbin LIU Jianbo FAN Junxuan 2001Chinese Science Bulletin2001,46,18:17
10The HuangZaoSi Maize Genome Provides Insights into Genomic Variation and Improvement History of Maize显示文摘Maize is a globally important crop that was a classic model plant for genetic studies. Here, we report a 2.2 Gb draft genome sequence of an elite maize line, HuangZaoSi (HZS). Hybrids bred from HZS-improved lines (HILs) are planted in more than 60% of maize fields in China. Proteome clustering of six completed sequeneed maize genomes show that 638 proteins fall into 264 HZS-specific gene families with the majority of contributions from tandem duplication events. Resequencing and comparative analysis of 40 HZSrelated lines reveals the breeding history of HILs. More than 60% of identified selective sweeps were clustered in identity.by.descent conserved regions, and yield-related genes/QTLs were enriched in HZS characteristic selected regions. Furthermore, we dem on strated that HZS-specific family genes were not uniformly distributed in the genome but enriched in improvement/function.related genomic regions. This study provides an important and novel resource for maize genome research and expands our knowledge on the breadth of genomic variation and improvement history of maize.Chunhui Li Wei Song Yingfeng Luo Shenghan Gao Ruyang Zhang Zi Shi Xiaqing Wang Ronghuan Wang Fengge Wang Jidong Wang Yanxin Zhao Aiguo Su Shuai Wang Xin Li Meijie Luo Shuaishuai Wang Yunxia Zhang Jianrong Ge Xinyu Tan Ye Yuan Xiaochun Bi Hang He Jianbing Yan Yuandong Wang Songnian Hu Jiuran Zhao 2019Molecular Plant2019,12,3:15
11Microstructure characteristics and solidification behavior of wrought aluminum alloy 2024 rheo-diecast with self-inoculation method显示文摘One important problem in casting wrought aluminum alloys is the high tendency to the formation of hot tears in the solidification process.By using semi-solid metal(SSM) processing,the hot tearing tendency of alloys can be minimized during casting.In the present research,the semi-solid slurry of wrought aluminum alloy 2024 was firstly prepared with a novel self-inoculation method(SIM),and then the microstructure characteristics of the semi-solid slurry and the rheo-diecastings cast with the semi-solid slurry were investigated.The results indicate that finer and more uniform globular primary α-Al particles can be obtained when the semi-solid slurry are isothermally held for a short period within the semi-solid temperature range,and the primary α-Al particles without entrapped liquid are uniformly fine,globular grains in the rheo-diecastings.The holding temperature and time affect the solid fraction,particle size,and shape factor.After the semi-solid slurry is held at 625 ℃ for 3 min and 5 min,the optimal values for the average equivalent diameter are 70.80 μm and 74.15 μm,and for the shape factor are 1.32 and 1.42,respectively.The solidification process of the rheo-diecastings is composed of the following two distinct stages:primary solidification process and secondary solidification process.The secondary solidification process consists further of the following three stages:(1) direct growth of secondary primary(α 2) phase from the surface of the primary α-Al phase particles without re-nucleation,(2) independent nucleation and growth of α 3 phase from the residual liquid,and(3) eutectic reaction at the end.Li Yanlei Li Yuandong Li Chun Wu Huihui 2012China Foundry2012,9,4:15
12Comparative studies on histological and ultra-structure of the pituitary of different ploidy level fishes显示文摘The histological and ultra-structure of the pituitary in diploid red crucian carp(Carassius auratus red var.),triploid crucian carp and allotetraploid hybrids within and after the breeding season were comparatively studied.The result showed that there were six endocrine cell types in the pituitary of these three kinds of fishes,and there was an obvious difference in cell size among different ploidy level fishes.As for the same type of pituitary cells,the cell size was increased gradually with the in- creasing ploidy level.In the breeding season,the allotetraploid hybrids had higher proportion of go- nadotropin cells(GTH)than triploids,and the triploids had higher proportion of GTH than diploids.The results were related to the earlier sexual maturity of allotetraploid hybrids and sterility of triploid cru- cian carp.On the other hand,among the three kinds of fishes,the proportion of somatotropin(STH) cells in triploids crucian carp was the highest,whereas that in allotetraploid hybrids was the lowest. The results might be connected with the faster growth rate of triploids and slower growth rate of al- lotetraploid hybrids.In addition,in GTH cells of meso-adenohypophysis after the breeding season, there were many endocrine particles in triploids,while those endocrine particles were released from the cells in allotetraploids and diploids.This result showed that the sterility of triploid crucian carp might be related to the hormone which was not released from the GTH cells.In a word,the present study indicated that the differences in the structure of pituitary among different ploidy level fishes contributed to their difference in the growth rate and gonadal development.LONG Yu LIU Shaojun HUANG Weiren ZHANG Jian SUN Yuandong ZHANG Chun CHEN Song LIU Jinghui LIU Yun 2006Science China(Life Sciences)2006,49,5:13
13Microstructure,mechanical and corrosion properties of Mg-2Dy-xZn(x=0,0.1,0.5 and 1 at.%)alloys显示文摘Microstructure,mechanical and corrosion properties of as-cast Mg-2Dy-xZn(x=0,0.1,0.5,and 1)(at.%)alloys were investigated.The microstructures of the as-cast Mg-2Dy and Mg-2Dy-0.1Zn alloys mainly consisted ofα-Mg phase and Mg_(24)Dy_(5)eutectic phase.With 0.5 at.%Zn addition,Mg_(12)ZnDy phase with 18R-type long period stacking ordered(LPSO)structure and Mg_(2)Dy phase precipitated at the grain boundaries.When the content of Zn is 1 at.%,only the Mg_(3)Zn_(3)Dy_(2)phase formed in theα-Mg matrix.The electrochemical measurements and immersion testing results indicated that the Mg-2Dy-0.1Zn alloy exhibited the best corrosion resistance.It revealed that the morphology,scale,amount and distribution of the second phase have a great effect on the corrosion resistance of alloy.Additionally,the tensile testing results showed that the Mg-2Dy-0.5Zn alloy exhibited the higher tensile strength and good elongation,especially at 200℃.The improvement of mechanical properties was mainly due to the strengthening of LPSO phase and grain refinement of α-Mg.Guangli Bi Yuandong Li Shijun Zang Jianbin Zhang Ying Ma Yuan Hao 2014Journal of Magnesium and Alloys2014,2,1:13
14Principal aspects of the Ordovician biotic radiation显示文摘The Ordovician radiation is among the major bioevents in earth history that have drawn great attention from geologists all over the world, and there have been hundreds of publications treating various aspects of this radiation. The study of the event involves a broad spectrum of research fields and concerns many scientific questions. Many opinions and hypotheses have been proposed on the triggering and controlling factors of the radiation. Herein the authors critically review the study of the Ordovician radiation and dissect four principal aspects by synthesizing the studies over the past years: (1) relationships of the radiation to fossil clades, ecotypes, and environments, such as water depth, latitude, and climate; (2) the ecological structure and food webs of Ordovician marine organisms; (3) fossil records and true biodiversities; and (4) likely triggering and controlling factors of the Ordovician radiation. The authors also recommend approaches to furthering studies of these aspects.ZHANG YuanDong,ZHAN RenBin,FAN JunXuan,CHENG JunFeng & LIU Xiao LPS, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China 2010Science China Earth Sciences2010,53,3:13
15A regional tectonic event of Katian(Late Ordovician) age across three major blocks of China显示文摘The present paper deals with a tectonic event of Late Ordovician age affecting three blocks of China,i.e.South China,North China and Tarim.In the North China and the Tarim platforms,as well as their marginal belts,there was a regional uplift during the early Katian Stage of the Ordovician.The uplift was indicated by the unconformities between the Ordovician successions and overlying late Paleozoic strata.New biostratigraphic studies of conodonts and graptolites from many sections at Longxian and Yaoxian,North China shows that the youngest Ordovician strata are of the early Katian age corresponding to graptolite Diplacanthograptus spiniferus Biozone.The same level has been recognized to represent the uppermost Ordovician in the platform area of Tarim,whereas in the marginal belt the top boundary of the Ordovician is slightly younger,corresponding to the graptolite Dicellograptus complanatus Biozone.Thus,the regional uplift in North China and Tarim is shown by the disconformity between the early Katian strata and Late Paleozoic strata,the onset coinciding with that of the Kwangsian Orogeny in South China.The designation Kwangsian Orogeny later fell into disuse and was replaced by the term Caledonian Orogeny.However,in terms of geographic location,tectonic nature,and the timing of activity,the Caledonian Orogeny differs significantly from the orogenic event in South China,and the continued use of this term in South China is inappropriate and misleading.CHEN Xu BERGSTRM Stig M ZHANG YuanDong WANG ZhiHao 2013Chinese Science Bulletin2013,58,34:12
16Induction of gynogenesis in red crucian carp using spermatozoa of blunt snout bream显示文摘Gynogenetic 双在红鲫鱼鲤鱼(RCC )(Carassius auratus 红变化) 被导致从钝猪嘴鲷(B)(Megalabrama amblycephala ) 或从镜子鲤鱼(C) 的鸡蛋使用紫外照耀精子(Cyprinus carpio。L) 。精子被适当紫外剂量遗传上使失去活性,然后母亲的 DNA 在 0-4 ° C 与冷吃惊被复制。当使用 B 的精子时,起初喂的授精率,孵化的率和幸存是 52.6 ± 3.0 %, 23.6 ± 4.1 %和 15.7 ± 3.4 %分别地,并且起初喂的幸存比那显著地高( 11.3 ± 2.2%)当使用 C 的精子时( Cypripnus carpio 。L) 。根据词法特征,染色体数字和 gonadal 开发的度, gynogenetic RCC 能与 RCC ♀ 的控制混血儿被区分开来B♂ 。有红身体颜色, 100 个染色体和正常 gonadal 开发的个人是 syccessful gyogenetic RCC,当有 124 或 148 个染色体和推迟的 gonadal 开发的个人是混血儿时(RCC B ) 。三倍性的混血儿(RCC B )(2 岁) 是无菌的,但是 tetraploid 混血儿(RCC B ) 是二的性成熟的年龄。在现在的学习,与 C 的精子相比, B 的 spermatoxoa 的优点作为激活来源是那能增加起初 gynogentic 个人和 simplfy 喂 gynogenetic 的证实的幸存地位,它建议 B 的精子是为在鲫鱼鲤鱼导致 gynogenesis 的有效激活来源。SUN Yuandong TAO Min LIU Shaojun ZHANG Chun DUAN Wei SHEN Jiamin WANG Jing ZENG Chen LONG Yu LIU Yun 2007Progress in Natural Science:Materials International2007,17,2:10
17Biostratigraphic correlation of the Ordovician black shales in Tarim Basin and its peripheral regions显示文摘Ordovician black shales are widely distributed in the Tarim Basin and its peripheral regions,and some of them may serve as potential hydrocarbon source rocks.The present study of the Ordovician graptolite fauna from these shales,together with the yielded conodonts and chitinozoans etc.,permits a refined correlation of the rocks.Based mainly on a new collecting of the graptolites and a study of the faunas in Kalpin and Kuruktag regions,and the successful identification of the new graptolite material from a few drill cores within the basin,we are able to update our knowledge of the Ordovician in the regions,and draw some conclusions:(1) The most widespread distribution of the black shales in the Tarim Basin and its peripheral regions,which correspond to the Nemagraptus gracilis Zone,may be related to a global sea-level rise during this time interval.(2) Black shales of Ordovician occur most frequently and extensively in the Kuruktag(also spelled as Quruq Tagh) region in east-ern Tianshan Mountains,spanning Tremadocian to mid-Katian(D.spiniferus Zone) temporally and extending southeastwards into Manjiaer Depression.The black shales of the D.spiniferus Zone may even extend into the central Tarim Basin.(3) Three different bio-and litho-facies belts(Bachu:carbonate platform and reef belt;Kalpin-Aksu:marginal platform and upper slope belt;Wushi:slope belt) are recognized in the northwestern Tarim Basin.(4) The internationally well-correlated Saergan black shale,which has been considered to possess high potential for hydrocarbon source rock,may possess a restricted distribution in the Kalpin and Aksu areas.CHEN Xu ZHANG YuanDong LI Yue FAN JunXuan TANG Peng CHEN Qing ZHANG YuanYuan 2012Science China Earth Sciences2012,55,8:8
18Diversity history of Ordovician graptolites and its relationship with environmental change显示文摘Statistical analysis based on global data indicated that the planktonic graptolites presented a distinguished pattern from that of benthic communities during the great Ordovician biodiversification. The graptolites started to diversify from the beginning of Ordovician and reached an acme in the early Middle Ordovician, but subsequently underwent a steady decline to the end of Ordovician. During the Ordovician, many clades of the graptolites made their originations, flourishing and replacements. However, in different regions and distinct environments across the world, graptolites may presumably display distinct patterns of radiation and evolution, a hypothesis to be tested. Herein a study of the graptolite diversity in the Early to Middle Ordovician in the Upper Yangtze Region (Platform) and Jiangnan Region (Slope), South China, is conducted. The results indicate that graptolites underwent a remarkable increase in both regions, but with distinct magnitude, scope, process and patterns. The diversification of graptolites in the Upper Yangtze Region, though less prominent, is divided into four stages and includes two peaks. In the Jiangnan Region, the graptolite diversification is far more prominent and includes three stages and one peak. Based on the distinct diversity histories and composition of graptolites in the two representative regions, a 'deep-water origin and shallow-water dispersal' model is proposed for the Ordovician graptolite faunas. According to the model, the major graptolite faunas of Ordovician originated in the deep-water region on the continental slope, the source of the graptolite novelties, and subsequently spread into shallow-water region on the shelf. Besides, we also conduct a comparison study of the Ordovician graptolite diversity in South China and other major regions. The results display that the graptolites diversified globally in the Early and Middle Ordovician. At the beginning of Ordovician, graptolites underwent a significant ecological innovation of graptolites: planktonic forms were derived from their benthic ancestors. This derivation resulted in the great guild expansion of graptolites. In late Early Ordovician (Floian), the global expansion of graptolites commenced. From the Floian to the end of Middle Ordovician, the graptolites diversity increased remarkably and displayed three peaks for all the regions. However, the peaks are somewhat distinct in magnitude and timing among regions. The Darriwilian peak is prominent in both South China and Baltic region, but inconspicuous in Australasia. No close relationship between the graptolite diversification and the palaeolatitudes are supported herein. Instead, the graptolite diversification seems to coincide with the global sea-level rises, suggesting a possible intrinsic relationship between them.Zhang YuanDong Chen Xu 2008Science China Earth Sciences2008,51,2:8
19XPA A23G polymorphism is associated with the elevated response to platinum-based chemotherapy in advanced non-small cell lung cancer显示文摘DNA 修理能力(DRC ) 向基于铂的化疗与癌症房间的敏感被相关。我们假设那在 DNA 的基因多型性修理基因 XPA (干皮病 pigmentosum 组 A )和 XPG (干皮病 pigmentosum 组 G )( ERCC5 ,切除修理跨互补的组 5 ),它在 DNA 修理效率导致内部个人的差别,可以在先进非小的房间肺癌症( NSCLC )预言临床的反应到铂代理人病人。在这研究,我们发现 XPA A23G 多型性的 A G 变化显著地增加了反应到基于铂的化疗。在 XPG His46His 的多型性与减少的治疗回答被联系,但是不是统计上重要的。Jifeng Feng Xinchen Sun Ning Sun Shukui Qin Fan Li Hongyan Cheng Baoan Chen YuanDong Cao Jun Ma Lu Cheng Zuhong Lu Jiazhong Ji Yingfeng Zhou 2009Acta Biochimica et Biophysica Sinica2009,41,5:8
20LSECtin on tumor-associated macrophages enhances breast cancer sternness via interaction with its receptor BTN3A3显示文摘Macrophages have bee n suggested to con tribute to con structing a cancer stem cell(CSC)niche.However,whether and how macrophages regulate the activity of CSCs through juxtacrine signaling are poorly understood.Here we report LSECtin,a transmembrane protein highly expressed on tumor-associated macrophages(TAMs),enhances sternness of breast cancer cells(BCCs).We identified BTN3A3,a B7 family member with previously unknown functions as the receptor for LSECtin on BCCs responsible for stemness-promoting effect of LSECtin.In mice bearing human tumor xenografts,either macrophage-specific ablation of LSECtin or silencing of BTN3A3 in BCCs decreased CSC frequency and tumor growth.Admixture of LSECtin-positive macrophages increased the tumorigenic activity of BCCs dependent on BTN3A3.Disruption of the LSECtin-BTN3A3 axis with BTN3A3-Fc or anti-BTN3A3 mAb has a therapeutic effect on breast cancer.These findings define a juxtacrine signaling mechanism by which TAMs promote cancer stemness.Targeting this axis in the CSC niche may provide potential therapies to breast cancer.Di Liu Qian Lu Xing Wang Jun Wang Ning Lu Zefei Jiang Xiaopeng Hao Jianbin Li Jing Liu Pengbo Cao Guilin Peng Yuandong Tao Dianyuan Zhao Fuchu He Li Tang 2019Cell Research2019,29,5:8
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