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| 1 | High-resolution geochemistry records of climate changes since late-glacial from Dajiuhu peat in Shennongjia Mountains,Central China显示文摘A peat core with depths of 297 cm was obtained from the Dajiuhu Basin(31°29′27″N,109°59′45″E,1760 m)in Hubei Province,Central China.10 AMS ages provide a time control and reveal that this core spans the past about 16.0 kaBP(calibrated age)(1 4C age:13.3 kaBP).Multi-proxy indexes analysis of geochemistry shows the following character of climate and environmental changes since about 16 kaBP:(1) The climate during the late-glacial period was cold and wet as a whole,but fluctuated continually.11.4- 12.6 cal.kaBP,12.6-15.2 cal.kaBP and 15.2-16 kaBP were corresponding respectively to the Younger Drays,Bφlling-Allerφd Warm Period and the Oldest Drays.(2)Inheriting the some climate characteristics of the late-glacial,the climate during the early-Holocene was wet and temperature increased gradually,during which an obvious dry event around 10.6 cal.kaB appeared.(3)The climate during the mid-Holocene was genarally warm and wet.During 9.2-7.5 kaBP,temperature increased gradually, precipitation was less comparatively and the 8.2 kaBP cold event which might be representative in the globe was reflected markedly.Then,multi-proxy records were relatively stable during 6.7-4.2 kaBP, which shows the best water and thermal condition in the Holocene Optimum.(4)Around 4.2 kaBP,the climate and environment transform from warm and wet to cool and dry,which may result in the collapse of the Neolithic Culture and midwifery the civilization of Xia Dynasty in this region.After 0.9 kaBP,the climate turned cool and wet.Climate and environmental changes archived in Dajiuhu peat respond to the global changes since the late-glacial period and can be contrasted to the changes recorded in other high-resolution archives from the East Asia Monsoon region,which take on the variety model that the monsoon strengthened abruptly after the late-glacial,was strong during the early Holocene,subse- quently declined and became weak after the middle Holocene with dry climate.According to our analysis,the driving mechanism should be the response of solar radiation changes in the East Asia Monsoon region at middle latitudes. | MA ChunMei ZHU Cheng ZHENG ChaoGui WU ChunLin GUAN Yong ZHAO ZhiPing HUANG LinYan HUANG Run | 2008 | Chinese Science Bulletin2008,53,S1: | 19 |
| 2 | Simulation and study on mitigation measures of frequent subsynchronous oscillation with low amplitude at multi-power plants显示文摘Subsynchronous oscillation (SSO) with low amplitude that exceeds cumulative fatigue threshold of the generator shaft frequently could significantly reduce the shaft's service life, which is a new SSO problem that emerges in recent years. According to the real recording oscillograph, the basic reason for frequently over-threshold SSO with low amplitude at multi-power plants was analyzed based on Hulunbuir League system. The sensitivities of the electrical damping to the main electrical parameters in the contributing loop of subsynchronous torsional interaction were calculated. Based on the sensitivities, a simulation method was presented, which was used to excite the same oscillation as the actual case by exerting disturbance on the firing angle. The limitation of wide-band and narrow-band supplementary subsynchronous damping controller (SSDC) for mitigating this kind of SSO was analyzed based on the electromagnetic transient simulation model of Hulunbuir League system. The difference of supplementary excitation damping controller (SEDC) and parallel-form FACTS connected to the generator terminal was compared from the aspects of response time and the ability of damping torque supplying. The analysis indicates that their response time is similar but FACTS has stronger ability of damping torque supplying than SEDC. Time-domain simulation method was used to compare the mitigation effects of SEDC, static var compensator (SVC) and static synchronous compensator (STATCOM). Considering the mitigation effect, the floor space limit of the power plant and so on, STATCOM was considered as the best mitigation measure. A control strategy of cascaded STATCOM for engineering application was presented and the capacity for SSO mitigation as well as output characteristics was analyzed. The analysis indicates that STATCOM using the proposed control strategy has better mitigation effect and output characteristics with smaller capacity. | XIAO XiangNing ZHANG Jian GAO BenFeng WU YunSheng LUO Chao GUO ChunLin YANG Lin | 2013 | Science China(Technological Sciences)2013,56,6: | 13 |
| 3 | Simultaneous Screening of 733 Pesticide Residues in Fruits and Vegetables by a GC/LC-Q-TOFMS Combination Technique显示文摘In this paper,we report the construction of two accurate mass databases and the development of a combination detection method that simultaneously screens for 733 pesticide and chemical contaminant multi-residues via high-throughput liquid chromatography(LC)-and gas chromatography(GC)-quadru pole-time-of-flight mass spectrometry(Q-TOFMS).This work demonstrates that electronic mass spectral standards may replace chemical-source standard materials as references through one sample preparation and the combination of GC/LC-Q-TOFMS screening.This cutting-edge technique has also replaced multiresidue determination using targeted detection with non-targeted screening.The pesticide residue types,sensitivity,recovery,and reproducibility of this combination technique are evaluated in eight fruit and vegetable matrices.This technique shows three advantages:①In comparison with the discovery capability of a single technique,the combination technique shows an improvement of 51.1%(GC-QTOFMS)and 39.6%(LC-Q-TOFMS),respectively;②the combination technique can satisfy a screening limit lower than 10μg·kg^-1 and meet the requirements of“uniform standards,”although some of the pesticide residues could be optimized to further improve screening sensitivity;③over 488 pesticides with recoveries between 60%-120%and relative standard deviation(RSD)<20%at a spiked level of 10μg·kg^-1 were detected with the combination technique in eight different matrices.From 2012 to 2017,this combination technique was applied in an investigation to screen pesticide residues from 1384 sampling locations for 38138 batched samples covering 18 categories and 134 types of fruits and vegetables obtained from across the mainland of China.After statistical analysis,533 pesticides in 115891 determinations were detected,and the regularity of pesticides in the fruits and vegetables sold on the Chinese market was shown. | Guofang Pang Qiaoying Chang Ruobin Bai Chunlin Fan Zijuan Zhang Hongyuan Yan Xingqiang Wu | 2020 | Engineering2020,6,4: | 11 |
| 4 | Multifunctional barium titanate ceramics via chemical modification tuning phase structure显示文摘Global environmental concerns on the toxicity of lead-based piezoelectrics impel the great mass fervor on investigations of lead-free alternatives.Barium titanate(BaTiO3,BT)ceramics,the first discovered perovskite ferroelectrics,were widely employed to fabricate dielectric capacitors from 1950s.Since a piezoelectric breakthrough was achieved via chemical modification,intensive researches have been performed embracing lead-free BT-based piezoelectrics and their extensional functionalities.In this review,we encompass the stateof-the-art progress on chemical modification tuning phase structure toward advanced electrical properties in BT-based ceramics.Generally,modulated regularity of cations substitution on phase transition is summarized and clarified.Then,we highlight the common methodologies of phase structure(phase boundary,relaxor phase,room-temperature phase transition,etc.)design for optimizing piezoelectricity,electrostrictive strain,electrocaloric,dielectric energy storage or permittivity performances,and cover the noticeable developments and relevant physical mechanisms.Finally,perspectives and challenges on future research issues are featured.This review proposes to exert the significant guidance and service for material design of BT-based and other lead-free perovskite materials with superior functionalities. | Chunlin Zhao Yanli Huang Jiagang Wu | 2020 | InfoMat2020,2,6: | 9 |
| 5 | Thick Miocene eolian deposits on the Huajialing Mountains:The geomorphic evolution of the western Loess Plateau显示文摘The geomorphic evolution of northwestern China during the Cenozoic has been a subject of much geological interest because of its link with the uplift of the Himalayan-Tibetan complex.Much information about these changes is recoverable from the sedimentary sequences of the region.We report here on the thick eolian deposits mantling the Huajialing Mountains,a relatively flat mountain range in the western Loess Plateau.Correlation of magnetic susceptibility stratigraphy with the QA-I Miocene eolian sequence dates a 134.7 m section(NL-VII) for the interval from 18.7 to 11.8 Ma,as confirmed by micro-mammalian fossils.These eolian deposits demonstrate a much wider distribution of the Miocene eolian deposits,and also indicate that the topography contrasts in the western Loess Plateau,including the uplifts of the Huajialing Mountains and the bedrock highlands in the Qinan region,were formed by the early Miocene.The near-continuous Miocene eolian sequence from 18.7 to 11.8 Ma indicates that the substratum of Huajialing had not experienced any intense tectonic changes during this time interval,which suggests further,the relative tectonic stability of the nearby Tibetan Plateau. | ZHAN Tao GUO ZhengTang WU HaiBin GE JunYi ZHOU Xin WU ChunLin ZENG FangMing | 2011 | Science China Earth Sciences2011,54,2: | 7 |
| 6 | Pore throat characteristics of tight sandstone of Yanchang Formation in eastern Gansu,Ordos Basin显示文摘An important factor to evaluate reservoir quality is the pore-throat size.However,the strong heterogeneity makes it difficult to characterize the pore-throat distribution in tight reservoirs.The field emission scanning electron microscope(FESEM),high pressure mercury injection and rate-controlled mercury injection are used to investigate the pore-throat size distribution in tight sandstone reservoirs of Member 7 of the Yanchang Formation in eastern Gansu,Ordos Basin,and studies of the pore throat size controlling on physical property of the tight sandstone reservoirs are also carried out.The result shows that the pore type is mainly dominated by the residual intergranular pore,dissolution pore,micropore and a few micro-fractures;the high-pressure mercury injection experiment indicates that the pore-throat size ranges from 0.0148 μm to 40mm,the pore throat more than 1 mm is less;the ratecontrolled mercury injection experiment reveals that for samples with different physical properties,the pore radius mainly varies from 80 μm to 350 μm;the throat radius exhibits the strong heterogeneity,and is from 0.12 μm to 30μm;the pore-throat size can be effectively characterized by combination of high-pressure and rate-controlled mercury injections,and it varies from 0.0148 μm to 350 μm.The permeability is mainly controlled by the large pore throat(>R_(50))which accounts for a small proportion;in the tight sandstone with the permeability greater than 0.1 mD,the permeability is mainly controlled by the micropore and mesopore;in the tight sandstone with the permeability smaller than 0.1 mD,the permeability is mainly controlled by the nanopore and micropore;the proportion of small pore throat increases with reduction of permeability,it is important that the small pore throat influences the reservoir storage property though its effect on permeability are small. | Hao Wu Chunlin Zhang Youliang Ji Rui'e Liu Shang Cao Sheng Chen Yunzhao Zhang Ye Wang Wei Du Gang Liu | 2018 | Petroleum Research2018,3,1: | 7 |
| 7 | Toward automatic estimation of urban green volume using airborne LiDAR data and high resolution Remote Sensing images显示文摘城市的绿体积是为分析城市的植被结构,生态的评估,和绿经济的评价的重要指示物。这份报纸为城市的绿体积联合的自动化评价建议一个基于目标的方法三维(3D ) 从在空中的轻察觉的信息并且变化(激光雷达) 从高分辨率的数据和植被信息遥远地通过 Lujiazui 区域的案例研究察觉到图象,上海,中国。在空中的在红外线附近的相片被用于识别城市的植被分发的高分辨率。在空中的激光雷达数据提议提取单个树并且测量树的属性的可能性,例如树高度和王冠直径。在这研究,单个树和草地作为城市的植被的独立对象被识别,并且城市的绿卷作为二宽广部分的和被计算:单个树体积和草地体积。方法由后面的步骤组成:产生并且过滤规范的数字表面模型( nDSM ),定位本地最大值点,分割植被,提取基于规范的差别植被索引( NDVI )的城市的植被的 nDSM 单个树王冠和草地反对,并且计算每个植被目标的城市的绿体积。结果在 Lujiazui 区域显示出数量和城市的绿体积的分发特征,并且为城市的绿计划和管理提供珍贵参数。激光雷达数据和图象数据的综合申请介绍一个有效方法估计城市的绿体积,这也从这份报纸被结束[出版摘要] | Yan HUANG Bailang YU Jianhua ZHOU Chunlin HU Wenqi TAN Zhiming HU Jianping WU | 2013 | Frontiers of Earth Science2013,7,1: | 6 |
| 8 | A new species of the genus Crocidura from China based on molecular and morphological data(Eulipotyphla: Soricidae)显示文摘A new species of white-toothed shrew,Crocidura anhuiensis Zhang,Zhang&Li,sp.nov.is described from Mount Huang,China.Genetic sequence(mt DNA Cyt b gene)and morphological(external and skull)data are used to distinguish this newly discovered species.The phylogenetic analysis shows that the materials of this work are monophyletic and allied to C.attenuata by the uncorrected genetic distance 4.9–5.1%,which suggests a species-level divergence.Morphologically,the materials are different from C.attenuata by presenting a greater proportion of tail-to-body ratio and the presence of an obvious tooth root in the mandible.Based on those data,the unnamed species is described as a new species which is currently known only from the Wild Monkey Valley,Mount Huang,Anhui Province,China. | Heng Zhang Guiyou Wu Yanqing Wu Jianfei Yao Shuo You Chencheng Wang Feng Cheng Jingjing Chen Mingxia Tang Chunlin Li Baowei Zhang | 2019 | Zoological Systematics2019,44,4: | 5 |
| 9 | N-doped graphene and TiO_2 supported manganese and cerium oxides on low-temperature selective catalytic reduction of NO_x with NH_3显示文摘A series of N-doped graphene(NG)and TiO_2 supported MnO_x–CeO_2 catalysts were prepared prepared by a hydrothermal method.The catalysts with different molar ratios of Mn/Ce(6:1,10:1,15:1)were investigated for the low-temperature selective catalytic reduction(SCR)of NO_x with NH_3.The synthesized catalysts were characterized by HRTEM,SEM,XRD,BET,XPS,and NH_3-TPD technologies.The characterization results indicated that manganese and cerium oxide particles dispersed on the surface of the TiO_2–NG support uniformly,and that manganese and cerium oxides existed in different valences on the surface of the TiO_2–NG support.At Mn element loading of 8 wt%,MnO_x–CeO_2(10:1)/TiO_2–1%NG displayed superior activity and improved SO_(2 )resistance.On the basis of the catalyst characterization,excellent catalytic performance and SO_2 tolerance at low temperature were attributed to the high content of manganese with high oxidation valence,extensive oxidation of NO into NO_2 by CeO_2 and strong NO adsorption capacity,and electron transfer of N-doped graphene. | Chunlin ZHAO Yanxia WU Hailong LIANG Xi CHEN Jie TANG Xianzhong WANG | 2018 | Journal of Advanced Ceramics2018,7,3: | 5 |
| 10 | Radiosensitization of human pancreatic cancer by piperlongumine analogues显示文摘Radiotherapy is commonly used to treat advanced pancreatic cancers and can improve survival by2 months in combination with gemcitabine.However,prognosis and survival improvement remain unsatisfactory,and effective therapies are urgently needed.Piperlongumine has been demonstrated to have therapeutic potentials against various cancers.In this study,we synthesized a series of piperlongumine derivatives and provided evidence that piperlongumine derivatives could be used as effective radiosensitizers in pancreatic cancer.Two compounds enhanced the radiosensitivity of Panc-1 and SW1990 cells.In a pancreatic bi-flank xenograft tumor model,they significantly inhibited tumor growth.Piperlongumine derivatives could induce reactive oxygen species(ROS)expression and regulate the Keapl-Nrf2 protective pathway with enhancement of radiation-induced DNA damage,G2/M-phase cell cycle arrest,and apoptosis.Collectively,our data offer a proof of concept for the use of piperlongumine derivatives as a novel class of radiosensitizers for the treatment of pancreatic cancer. | Hao Ma Yuelin Wu Wannian Zhang Huojun Zhang Zhenyuan Miao Chunlin Zhuang | 2021 | Chinese Chemical Letters2021,32,3: | 4 |
| 11 | SHP2 regulates skeletal cell fate by modifying SOX9 expression and transcriptional activity显示文摘Chondrocytes and osteoblasts differentiate from a common mesenchymal precursor, the osteochondroprogenitor(OCP), and help build the vertebrate skeleton. The signaling pathways that control lineage commitment for OCPs are incompletely understood. We asked whether the ubiquitously expressed protein-tyrosine phosphatase SHP2(encoded by Ptpn11) affects skeletal lineage commitment by conditionally deleting Ptpn11 in mouse limb and head mesenchyme using 'Cre-lox P'-mediated gene excision.SHP2-deficient mice have increased cartilage mass and deficient ossification, suggesting that SHP2-deficient OCPs become chondrocytes and not osteoblasts. Consistent with these observations, the expression of the master chondrogenic transcription factor SOX9 and its target genes Acan, Col2a1, and Col10a1 were increased in SHP2-deficient chondrocytes, as revealed by gene expression arrays, q RT-PCR, in situ hybridization, and immunostaining. Mechanistic studies demonstrate that SHP2 regulates OCP fate determination via the phosphorylation and SUMOylation of SOX9, mediated at least in part via the PKA signaling pathway. Our data indicate that SHP2 is critical for skeletal cell lineage differentiation and could thus be a pharmacologic target for bone and cartilage regeneration. | Chunlin Zuo Lijun Wang Raghavendra M.Kamalesh Margot E.Bowen Douglas C.Moore Mark S.Dooner Anthony M.Reginato Qian Wu Christoph Schorl Yueming Song Matthew L.Warman Benjamin G.Neel Michael G.Ehrlich Wentian Yang | 2018 | Bone Research2018,6,2: | 3 |
| 12 | Environmental exposure and flux of thallium by industrial activities utilizing thallium-bearing pyrite显示文摘Thallium(Tl) is a typical toxic heavy metal,with higher toxicity to mammals than Hg,Cd,and Pb.Accurate assessments of its environmental exposure and flux are central to effective management and control of Tl pollution.This paper first presents in detail the environmental exposure and flux of Tl by typical industrial activities utilizing Tl-bearing pyrite minerals to produce sulfuric acid.For this purpose,sequential extraction and Inductively Coupled Plasma Mass Spectrometry(ICP-MS) were used to investigate total content and geo-chemical partitioning of Tl in raw pyrite ores and solid roasting wastes,thereby uncovering Tl distribution and transformation during the production process.Results showed that some portions of Tl bearing in the minerals went into vapor,which transferred Tl into different processes;and some portions of Tl went into water during the gas washing procedure,leaving some other portions remained in the solid slags.More importantly,detailed investigation revealed that 40% of Tl in the pyrite minerals was active,among which 25% of Tl originally in the pyrite minerals was washed into water during gas cleaning process and 15% of active Tl retained in the slags.The latter portion of active Tl could be possibly transferred to the soil or water with the slag deposal or being reused;and 60% of Tl remained relatively stable in the residual phase. | CHEN YongHeng WANG ChunLin LIU Juan WANG Jin QI JianYing WU YingJuan | 2013 | Science China Earth Sciences2013,56,9: | 3 |
| 13 | Potassium sodium niobate based lead-free ceramic for high-frequency ultrasound transducer applications显示文摘The BiAlO_(3)(BA)and(Bi_(0.5)Na_(0.5))ZrO_(3)(BNZ)are selected to form a solid solution with(K_(0.48)Na_(0.52))NbO_(3) via traditional solid state technique to optimize the electrical performance and temperature stability of KNNbased lead-free ceramics,simultaneously.Here we show that doped BA has a great influence on phase structure,morphologies,and electrical properties.The XRD patterns and dielectric constant versus temperature curves reveal that an increase in the BA content results in a transform of phase structures from a coexistence state of rhombohedral,orthorhombic and tetragonal phases to pseudocubic phase.Owing to the construction of R-O-T phase boundary,optimized performances(T_(C)~336℃,d_(33)~306 pC/N,kp=0.48)are obtained in 0.962(K_(0.48)Na_(0.52))NbO_(3)-0.003BiAlO_(3)-0.035(Bi_(0.5)Na_(0.5))ZrO_(3)(KNN-3)ceramics.Based on the sintered KNN-3 ceramic samples,high-frequency ultrasound imaging transducers are designed and fabricated,which exhibits a high center frequency of 24.5 MHz,a broad -6 dB bandwidth of 97% and a high-sensitivity.Finally,the imaging characteristic of the lead-free transducers is demonstrated via ex vivo imaging of biological tissue structure.As environment friendly materials,the excellent electrical and acoustic performance of developed KNN-based ceramics has great potential for practical applications. | Jie Xing Laiming Jiang Chunlin Zhao Zhi Tan Qian Xu Jiagang Wu Qiang Chen Dingquan Xiao Jianguo Zhu | 2020 | Journal of Materiomics2020,6,3: | 3 |
| 14 | Late Cretaceous Transpressional Fault System: A Case Study of the Yishu Fault Belt, Shandong Province, Eastern China显示文摘On the basis of field observations of the structures of three profiles from the Linshu region, deformation characteristics and the tectonic background of the Yishu fault belt in the Late Cretaceous–Early Cenozoic have been discussed in detail.Three structural profiles, whose deformations consist mainly of earlier transpressional faults and later normal faults, were developed for the Mengtuan Formation of the Lower Cretaceous Dasheng Group.Typical positive flower structures, duplex structures, and break-through faults were found in these profiles.On the basis of analyses of the structural deformation and previous geochronological studies, it was concluded that the earlier transpressional faults of the profiles were triggered by the sinistral transpression of the Yishu fault belt in the Late Cretaceous–Early Paleogene, and that the later normal faults, formed during the Late Paleogene–Neogene extension, truncated the earlier transpressional faults.With consideration of the tectonic evolution of the Tan-Lu fault belt and the different drift directions of the Pacific plate since the Cretaceous, we suggest that the major tectonic events of the Late Cretaceous–Neogene in eastern China were mainly controlled by the subduction of the Pacific plate. | LI Chunlin WANG Zongxiu WU Qingzi LIU Yongqing GAO Wanli TAN Yuanlong KUANG Hongwei LI Huijun | 2015 | Acta Geologica Sinica(English Edition)2015,89,5: | 3 |
| 15 | Glutamate synthase 1 is involved in iron-deficiency response and long-distance transportation in Arabidopsis显示文摘Iron is an essential microelement for plant growth.After uptake from the soil,iron is chelated by ligands and translocated from roots to shoots for sub-sequent utilization.However,the number of ligands in-volved in iron chelation is unclear.In this study,we identified and demonstrated that GLU1,which encodes a ferredoxin-dependent glutamate synthase,was involved in iron homeostasis.First,the expression of GLU1 was strongly induced by iron deficiency condition.Second,lesion of GLU1 results in reduced transcription of many iron-deficiency-responsive genes in roots and shoots.The mutant plants revealed a decreased iron concentration in the shoots,and displayed severe leaf chlorosis under the condition of Fe limitation,compared to wild-type.Third,the product of GLU1,glutamate,could chelate iron in vivo and promote iron transportation.Last,we also found that supplementation of glutamate in the medium can alleviate cadmium toxicity in plants.Overall,our results provide evidence that GLU1 is involved in iron homeo-stasis through affecting glutamate synthesis under iron deficiency conditions in Arabidopsis. | Man Cui Mengjun Gu Yaru Lu Yue Zhang Chunlin Chen Hong‐Qing Ling Huilan Wu | 2020 | Journal of Integrative Plant Biology2020,62,12: | 2 |
| 16 | A new species of the genus Crocidura(Mammalia:Eulipotyphla:Soricidae) from Mount Huang, China显示文摘In this study, a new species of white-toothed shrew, Crocidura huangshanensis Yang, BW Zhang & Li, sp. nov. was described based on five individuals collected from the Mt. Huang of China. Its morphological data and mt DNA sequences(Cyt b) were analyzed. Morphologically, C. huangshanensis Yang, BW Zhang & Li, sp. nov. is different from its congeners(C. anhuiensis and C. attenuata) by the body and skull smaller in size and the premolar and molar smoother, which are also different from other Southeast Asian Crocidura. The phylogenetic analysis shows that all individuals of C. huangshanensis Yang, BW Zhang & Li, sp. nov. merged into a single clade. In addition, the genetic distance between C. huangshanensis Yang, BW Zhang & Li, sp. nov. and other species of Crocidura is ranged from 9.8% to 15.3%, indicating a species-level divergence. The new species is currently distributed in the Wild Monkey Valley, located in Mt. Huang, China. | Liu Yang Heng Zhang Chenling Zhang Jun Wu Zhaocheng Wang Chunlin Li Baowei Zhang | 2020 | Zoological Systematics2020,45,1: | 2 |
| 17 | An environmental database and temporal and spatial distribution of Chinese paleoanthropological sites显示文摘A comprehensive database of paleoenvironmental settings for paleoanthropological sites provides a useful tool to explore the link between human evolution and paleoenvironmental changes. A preliminary GIS-based environmental database for paleoanthropological sites in China (EDPC) was constructed based on data collected from published literature. The database currently contains 1114 paleoanthropological sites. It will be available for online access following the establishment of relevant rules, and after improvement and further development through regular and sustained updates by internal and external users. Preliminary analyses using the GIS system yielded new evidence regarding human-environmental relationships. | WU ChunLin ZHANG Yan LI Qin GUO ZhengTang GAO Xing | 2011 | Chinese Science Bulletin2011,56,31: | 2 |
| 18 | Sequence Diversity and Enzyme Activity of Ferric-Chelate Reductase LeFRO1 in Tomato显示文摘Ferric-chelate reductase which functions in the reduction of ferric to ferrous iron on root surface is a critical protein for iron homeostasis in strategy I plants.LeFRO1 is a major ferric-chelate reductase involved in iron uptake in tomato.To identify the natural variations of LeFRO1 and to assess their effect on the ferric-chelate reductase activity,we cloned the coding sequences of LeFRO1 from 16 tomato varieties collected from different regions,and detected three types of LeFRO1(LeFR01^(MM),LeFRO1^(Ailsa) and LeFRO1^(Monita)) with five amino acid variations at the positions 21,24,112,195 and 582.Enzyme activity assay revealed that the three types of LeFRO1 possessed different ferric-chelate reductase activity(LeFRO1^(Ailsa)>LeFRO1^(MM)>LeFRO1^(Monita)).The 112th amino acid residue Ala of LeFRO1 is critical for maintaining the high activity of ferric-chelate reductase,because modification of this amino acid resulted in a significant reduction of enzyme activity.Further,we showed that the combination of the amino acid residue Ile at the site 24 with Lys at the site 582 played a positive role in the enzyme activity of LeFRO1.In conclusion,the findings are helpful to understand the natural adaptation mechanisms of plants to iron-limiting stress,and may provide new knowledge to select and manipulate LeFRO1 for improving the iron deficiency tolerance in tomato. | Danyu Kong Chunlin Chen Huilan Wu Ye Li Junming Li Hong-Qing Ling | 2013 | Journal of Genetics and Genomics2013,40,11: | 2 |
| 19 | A general truncated regularization framework for contrast-preserving variational signal and image restoration: Motivation and implementation显示文摘Variational methods have become an important kind of methods in signal and image restoration—a typical inverse problem. One important minimization model consists of the squared ?_2 data fidelity(corresponding to Gaussian noise) and a regularization term constructed by a potential function composed of first order difference operators. It is well known that total variation(TV) regularization, although achieved great successes,suffers from a contrast reduction effect. Using a typical signal, we show that, actually all convex regularizers and most nonconvex regularizers have this effect. With this motivation, we present a general truncated regularization framework. The potential function is a truncation of existing nonsmooth potential functions and thus flat on(τ, +∞) for some positive τ. Some analysis in 1 D theoretically demonstrate the good contrast-preserving ability of the framework. We also give optimization algorithms with convergence verification in 2 D, where global minimizers of each subproblem(either convex or nonconvex) are calculated. Experiments numerically show the advantages of the framework. | Chunlin Wu Zhifang Liu Shuang Wen | 2018 | Science China Mathematics2018,61,9: | 2 |
| 20 | Flabellariopteris, a new aquatic fern leaf from the Late Triassic of western Liaoning, China显示文摘An aquatic fern leaf,Flabellariopteris mii Sun gen.et sp.nov.from the Late Triassic of Western Liaoning,China,is described and proposed as the type species of the new morphortaxon of the Marsileaceae.The fossil leaves are preserved as impression.No fertile and rhizomatic materials are found.The leaves attached at a common point on the top of the petiole are composed of two leaflets joined basally in an opposite arrangement.The petiole is slender.The leaflet is fan-shaped or semi-circular,and commonly divided into four wedge-shaped lobes.Terminal margin of lobes is usually incised,incisions shallow or deep,with bluntly rounded or notched apex.The veins are conspicuously dichotomous,but anastomoses and marginal vein are absent.The unique morphological features,including twoparted thin leaflets,size,shape,veins and slender petiole,indicate that the present specimen represents an aquatic fern,which is the oldest fossil record and the first megafossil evidence assignable to Marsileaceae from the Triassic floras. | Chunlin Sun Tao Li Yuling Na Wenhao Wu Yunfeng Li Lixia Wang Lijun Zhang | 2014 | Chinese Science Bulletin2014,59,20: | 2 |