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| 1 | 5-Hydroxymethylcytosine signatures in circulating cell-free DNA as diagnostic biomarkers for human cancers显示文摘象 5-methylcytosine (5mC ) 和 5-hydroxymethylcytosine (5hmC ) 那样的 DNA 修正是知道在哺乳动物影响全球基因表示的 epigenetic 标记。在人的染色体,与基因表示的靠近的关联和高化学的稳定性给他们的流行,这些 DNA epigenetic 标记能为癌症用作理想的 biomarkers 诊断。利用一种高度敏感、选择的化学标记技术,我们这里报导在传播没有房间的 DNA ( cfDNA )并且在从最近与 colorectal 诊断的 260 个病人的一个队收集的配对的肿瘤和邻近的纸巾的 genomic DNA ( gDNA )的 5hmC 的染色体宽的介绍,胃,胰腺,从 90 个健康个人的肝或甲状腺癌症和正常纸巾。5hmC 主要在与开的染色质和容许的 histone 修正重合的 transcriptionally 活跃的区域被散布。柔韧的联系癌症的 5hmC 签名在 cfDNA 被识别为特定的癌症类型是特征的。传播 cfDNA 的 5hmC 底 biomarkers colorectal 和胃的癌症是高度预兆的并且比常规 biomarkers 优异并且比得上从织物活体检视的 5hmC biomarkers。因此,这新策略能从血样品的分析为癌症的诊断和预后导致有效、最低限度地侵略的方法的发展。 | Wenshuai Li Xu Zhang Xingyu Lu Lei You Yanqun Song Zhongguang Luo Jun Zhang Ji Nie Wanwei Zheng Diannan Xu Yaping Wang Yuanqiang Dong Shulin Yu Jun Hong Jianping Shi Hankun Hao Fen Luo Luchun Hua Peng Wang Xiaoping Qian Fang Yuan Lianhuan Wei Ming Cui Taiping Zhang Quan Liao Menghua Dai Ziwen Liu Ge Chen Katherine Meckel Sarbani Adhikari Guifang Jia Marc B Bissonnette Xinxiang Zhang Yupei Zhao Wei Zhang Chuan He Jie Liu | 2017 | Cell Research2017,27,10: | 30 |
| 2 | Investigation of Surface Integrity on TC17 Titanium Alloy Treated by Square-spot Laser Shock Peening显示文摘Laser shock peening(LSP) is an innovative surface treatment method,which has been shown to greatly improve the fatigue life of many metallic components.This work investigates surface integrity of TC17 titanium alloy treated by LSP with innovative square laser spot.Nd:glass laser with duration of 30 ns and spot size of 4 mm×4 mm is applied.The surface morphology and surface residual stress of the TC17 titanium alloy,treated with varying peening parameters such as laser power density and overlapping ratio,have been studied in detail.The results show that laser pulse energy greatly influences surface morphology and surface residual stress around single-spot treated areas,and compressive residual stresses are saturated as laser pulse energy is over 55 J.There are significantly different surface morphologies and residual stress distributions at the overlapped areas with different overlapping ratios.A relative smooth surface is produced with uniform compressive residual stress distribution at an overlapping ratio of 8 %.The experiment of residual stress relaxation is implemented by measuring residual stress at the center of four overlapped spots and by four point bending fatigue test at the frequency of 105 Hz.The compressive residual stresses induced by LSP are found to relax quite slowly under cyclic fatigue loading. | CAO Ziwen XU Haiying ZOU Shikun CHE Zhigang | 2012 | Chinese Journal of Aeronautics2012,25,4: | 27 |
| 3 | Development and application of an efficient gas extraction model for low-rank high-gas coal beds显示文摘 | Baiquan Lin | 2015 | International Journal of Coal Science & Technology2015,2,1: | 27 |
| 4 | Maize Genic Male-Sterility Genes and Their Applications in Hybrid Breeding: Progress and Perspectives显示文摘As one of the most important crops, maize not only has been a source of the food, feed, and industrial feedstock for biofuel and bioproducts, but also became a model plant system for addressing fundamental questions in genetics. Male sterility is a very useful trait for hybrid vigor utilization and hybrid seed production. The identification and characterization of genic male-sterility (GMS) genes in maize and other plants have deepened our understanding of the molecular mechanisms controlling anther and pollen development, and enabled the development and efficient use of many biotechnology-based male-sterility (BMS) systems for crop hybrid breeding. In this review, we summarize main advances on the identification and characterization of GMS genes in maize, and con struct a putative regulatory network controlling maize anther and pollen development by comparative genomic analysis of GMS genes in maize, Arabidopsis, and rice. Furthermore, we discuss and appraise the features of more than a dozen BMS systems for propagating male-sterile lines and producing hybrid seeds in maize and other plants. Finally, we provide our perspectives on the studies of GMS genes and the development of novel BMS systems in maize and other plants. The continuous exploration of GMS genes and BMS systems will enhance our understanding of molecular regulatory networks controlling male fertility and greatly facilitate hybrid vigor utilization in breeding and field production of maize and other crops. | Xiangyuan Wan Suowei Wu Ziwen Li Zhenying Dong Xueli An Biao Ma Youhui Tian Jinping Li | 2019 | Molecular Plant2019,12,3: | 24 |
| 5 | Autologous transplantation of bone marrow mesenchymal stem cells on diabetic patients with lower limb ischemia显示文摘学习骨头髓的自体同源的移植的功效和安全的目的有更低的手足局部缺血的糖尿病的病人上的间充质的干细胞。有更低的手足局部缺血的五十种类型 2 糖尿病的病人被注册并且使随机化到也的方法移植了组或控制组。病人在两个都,组接受了一样的常规治疗。同时,从每个移植病人的 20 ml 骨头髓被收集,并且间充质的干细胞被密度坡度 centrifugation 分开并且在有自体同源的浆液的媒介有教养。在在 vitro 的三星期的支持者文化以后, 7.32 ????????????????? 金 ???????????? ㈠ ?????? ┷? | Lu Debin Jiang Youzhao Liang Ziwen Li Xiaoyan Zhang Zhonghui Chen Bing | 2008 | Journal of Medical Colleges of PLA(China)2008,23,2: | 16 |
| 6 | ZmMs30 Encoding a Novel GDSL Lipase Is Essential for Male Fertility and Valuable for Hybrid Breeding in Maize显示文摘Genic male sterility (GMS) is very useful for hybrid vigor utilization and hybrid seed production. Although a large number of GMS genes have been identified in plants, little is known about the roles of GDSL lipase members in anther and pollen development. Here, we report a maize GMS gene, ZmMs30, which encodes a novel type of GDSL lipase with diverged catalytic residues. Enzyme kinetics and activity assays show that ZmMs30 has lipase activity and prefers to substrates with a short carbon chain. ZmMs30 is specifically expressed in maize anthers during stages 7-9. Loss of ZmMs30 function resulted in defective anther cuticle, irregular foot layer of pollen exine, and complete male sterility. Cytological and lipidomics analyses demonstrate that ZmMs30 is crucial for the aliphatic metabolic pathway required for pollen exine formation and anther cuticle development. Furthermore, we found that male sterility caused by loss of ZmMs30 function was stable in various inbred lines with different genetic background, and that it didn't show any negative effect on maize heterosis and production, suggesting that ZmMs30 is valuable for crossbreeding and hybrid seed production. We then developed a new multi-control sterility system using ZmMs30 and its mutant line, and demonstrated it is feasible for generating desirable GMS lines and valu. able for hybrid maize seed production. Taken together, our study sheds new light on the mechanisms of anther and pollen development, and provides a valuable male-sterility system for hybrid breeding maize. | Xueli An Zhenying Dong Youhui Tian Ke Xie Suowei Wu Taotao Zhu Danfeng Zhang Van Zhou Canfang Niu Biao Ma Quancan Hou Jianxi Bao Simiao Zhang Ziwen Li Yanbo Wang Tingwei Yan Xiaojing Sun Yuwen Zhang Jinping Li Xiangyuan Wan | 2019 | Molecular Plant2019,12,3: | 15 |
| 7 | Lipid Metabolism: Critical Roles in Male Fertility and Other Aspects of Reproductive Development in Plants显示文摘Fatty acids and their derivatives are essential building blocks for anther cuticle and pollen wall formation.Disruption of lipid metabolism during anther and pollen development often leads to genic male sterility(GMS).To date,many lipid metabolism-related GMS genes that are involved in the formation of anther cuticle,pollen wall,and subcellular organelle membranes in anther wall layers have been identified and characterized.In this review,we summarize recent progress on characterizing lipid metabolism-related genes and their roles in male fertility and other aspects of reproductive development in plants.On the basis of cloned GMS genes controlling biosynthesis and transport of anther cutin,wax,sporopollenin,and tryphine\r\Arabidopsis,rice,and maize as well as other plant species,updated lipid metabolic networks underlying anther cuticle development and pollen wall formation were proposed.Through bioinformatics analysis of anther RNA-sequencing datasets from three maize inbred lines(Oh43,W23,and B73),a total of 125 novel lipid metabolism-related genes putatively involved in male fertility in maize were deduced.More,we discuss the pathways regulating lipid metabolism-related GMS genes at the transcriptional and post-transcriptional levels.Finally,we highlight recent findings on lipid metabolism-related genes and their roles in other aspects of plant reproductive development.A comprehensive understanding of lipid metabolism,genes involved,and their roles in plant reproductive development will facilitate the application of lipid metabolism-related genes in gene editing,haploid and callus induction,molecular breeding and hybrid seed production in crops. | Xiangyuan Wan Suowei Wu Ziwen Li Xueli An Youhui Tian | 2020 | Molecular Plant2020,13,7: | 15 |
| 8 | Speciation with gene flow via cycles of isolation and migration:insights from multiple mangrove taxa显示文摘Allopatric speciation requiring an unbroken period of geographical isolation has been the standard model of neo-Darwinism. While doubts have been repeatedly raised, strict allopatry without any gene flow remains a plausible mechanism in most cases. To rigorously reject strict allopatry, genomic sequences superimposed on the geological records of a well-delineated geographical barrier are necessary. The Strait of Malacca,narrowly connecting the Pacific and Indian Ocean coasts, serves at different times either as a geographical barrier or a conduit of gene flow for coastal/marine species. We surveyed 1700 plants from 29 populations of 5 common mangrove species by large-scale DNA sequencing and added several whole-genome assemblies. Speciation between the two oceans is driven by cycles of isolation and gene flow due to the fluctuations in sea level leading to the opening/closing of the Strait to ocean currents. Because the time required for speciation in mangroves is longer than the isolation phases, speciation in these mangroves has proceeded through many cycles of mixing-isolation-mixing, or MIM, cycles. The MIM mechanism, by relaxing the condition of no gene flow, can promote speciation in many more geographical features than strict allopatry can. Finally, the MIM mechanism of speciation is also efficient, potentially yielding mn(m > 1) species after n cycles. | Ziwen He Xinnian Li Ming Yang Xinfeng Wang Cairong Zhong Norman C.Duke Chung-I Wu Suhua Shi | 2019 | National Science Review2019,6,2: | 14 |
| 9 | A mussel-inspired supramolecular hydrogel with robust tissue anchor for rapid hemostasis of arterial and visceral bleedings显示文摘In recent years,the developed hemostatic technologies are still difficult to be applied to the hemostasis of massive arterial and visceral hemorrhage,owing to their weak hemostatic function,inferior wet tissue adhesion,and low mechanical properties.Herein,a mussel-inspired supramolecular interaction-cross-linked hydrogel with robust mechanical property(308.47±29.20 kPa)and excellent hemostatic efficiency(96.5%±2.1%)was constructed as a hemostatic sealant.Typically,we combined chitosan(CS)with silk fibroin(SF)by cross-linking them through tannic acid(TA)to maintain the structural stability of the hydrogel,especially for wet tissue adhesion ability(shear adhesive strength=29.66±0.36 kPa).Compared with other materials reported previously,the obtained CS/TA/SF hydrogel yielded a lower amount of blood loss and shorter time to hemostasis in various arterial and visceral bleeding models,which could be ascribed to the synergistic effect of wound closure under wet state as well as intrinsic hemostatic activity of CS.As a superior hemostatic sealant,the unique hydrogel proposed in this work can be exploited to offer significant advantages in the acute wound and massive hemorrhage with the restrictive access of therapeutic moieties. | Ziwen Qiao Xueli Lv Shaohua He Shumeng Bai Xiaochen Liu Linxi Hou Jingjing He Dongmei Tong Renjie Ruan Jin Zhang Jianxun Ding Huanghao Yang | 2021 | Bioactive Materials2021,6,9: | 14 |
| 10 | Normal Structure and Function of Endothecium Chloroplasts Maintained by ZmMs33-Mediated Lipid Biosynthesis in Tapetal Cells Are Critical for Anther Development in Maize显示文摘Genic male sterility(GMS)is critical for heterosis utilization and hybrid seed production.Although GMS mutants and genes have been studied extensively in plants,it has remained unclear whether chloroplast-associated photosynthetic and metabolic activities are involved in the regulation of anther development.In this study,we characterized the function of ZmMs33/ZmGPAT6,which encodes a member of the glycerol-3-phosphate acyltransferase(GPAT)family that catalyzes the first step of the glycerolipid synthetic pathway.We found that normal structure and function of endothecium(En)chloroplasts maintained by ZmMs33-mediated lipid biosynthesis in tapetal cells are crucial for maize anther development.ZmMs33 is expressed mainly in the tapetum at early anther developmental stages and critical for cell proliferation and expansion at late stages.Chloroplasts in En cells of wild-type anthers function as starch storage sites before stage 10 but as photosynthetic factories since stage 10 to enable starch metabolism and carbohydrate supply.Loss of ZmMs33 function inhibits the biosynthesis of glycolipids and phospholipids,which are major components of En chloroplast membranes,and disrupts the development and function of En chloroplasts,resulting in the formation of abnormal En chloroplasts containing numerous starch granules.Further analyses reveal that starch synthesis during the day and starch degradation at night are greatly suppressed in the mutant anthers,leading to carbon starvation and low energy status,as evidenced by low trehalose-6-phosphate content and a reduced ATP/AMP ratio.The energy sensor and inducer of autophagy,SnRK1,was activated to induce early and excessive autophagy,premature PCD,and metabolic reprogramming in tapetal cells,finally arresting the elongation and development of mutant anthers.Taken together,our results not only show that ZmMs33 is required for normal structure and function of En chloroplasts but also reveal that starch metabolism and photosynthetic activities of En chloroplasts at different developmental stages are essential for normal anther development.These findings provide novel insights for understanding how lipid biosynthesis in the tapetum,the structure and function of En chloroplasts,and energy and substance metabolism are coordinated to maintain maize anther development. | Taotao Zhu Ziwen Li Xueli An Yan Long Xiaofeng Xue Ke Xie Biao Ma Danfeng Zhang Yijian Guan Canfang Niu Zhenying Dong Quancan Hou Lina Zhao Suowei Wu Jinping Li Weiwei Jin Xiangyuan Wan | 2020 | Molecular Plant2020,13,11: | 9 |
| 11 | Stochastic Dynamic Economic Dispatch of Wind-integrated Electricity and Natural Gas Systems Considering Security Risk Constraints显示文摘As the proportion of wind power generation increases in power systems,it is necessary to develop new ways for wind power accommodation and improve the existing power dispatch model.The power-to-gas technology,which offers a new approach to accommodate surplus wind power,is an excellent way to solve the former.Hence,this paper proposes to involve power-to-gas technology in the integrated electricity and natural gas systems(IEGSs).To solve the latter,on one hand,a new indicator,the scale factor of wind power integration,is introduced into the wind power stochastic model to better describe the uncertainty of grid-connected wind power;on the other hand,for quantizing and minimizing the impact of the uncertainties of wind power and system loads on system security,security risk constraints are established for the IEGS by the conditional value-at-risk method.By considering these two aspects,an MILP formulation of a security-risk based stochastic dynamic economic dispatch model for an IEGS is established,and GUROBI obtained from GAMS is used for the solution.Case studies are conducted on an IEGS consisting of a modified IEEE 39-bus system and the Belgium 20-node natural gas system to examine the effectiveness of the proposed dispatch model. | Zexing Chen Gelan Zhu Yongjun Zhang Tianyao Ji Ziwen Liu Xiaoming Lin Zexiang Cai | 2019 | CSEE Journal of Power and Energy Systems2019,5,3: | 8 |
| 12 | Unsteady aerodynamic characteristics of a horizontal wind turbine under yaw and dynamic yawing显示文摘Horizontal axis wind turbine(HAWT)often works under yaw due to the stochastic variation of wind direction.Yaw also can be used as one of control methods for load reduction and wake redirection of HAWT.Thus,the aerodynamic performance under yaw is very important to the design of HAWT.For further insight into the highly unsteady characteristics aerodynamics of HAWT under yaw,this paper investigates the unsteady variations of the aerodynamic performance of a small wind turbine under static yawed and yawing process with sliding grid method,as well as the there-dimensional effect on the unsteady characteristics,using unsteady Reynolds-averaged Navier-Stokes(URANS)simulations.The simulation results are validated with experimental data and blade element momentum(BEM)results.The comparisons show that the CFD results have better agreement with the experimental data than both BEM results.The wind turbine power decreases according to a cosine law with the increase of yaw angle.The torque under yaw shows lower frequency fluctuations than the non-yawed condition due to velocity component of rotation and the influence of spinner.Dynamic yawing causes larger fluctuate than static yaw,and the reason is analyzed.The aerodynamic fluctuation becomes more prominent in the retreating side than that in the advancing side for dynamic yawing case.Variations of effective angle of attack and aerodynamic forces along the blade span are analyzed.The biggest loading position moves from middle span to outer span with the increase of yaw angle.Three-dimensional stall effect presents load fluctuations at the inner board of blade,and becomes stronger with the increase of yaw angle. | Zhaoliang Ye Xiaodong Wang Ziwen Chen Luyao Wang | 2020 | Acta Mechanica Sinica2020,36,2: | 8 |
| 13 | The origin, diversification and adaptation of a major mangrove clade (Rhizophoreae) revealed by whole-genome sequencing显示文摘Mangroves invade some very marginal habitats for woody plants—at the interface between land and sea.Since mangroves anchor tropical coastal communities globally, their origin, diversification and adaptation are of scientific significance, particularly at a time of global climate change. In this study, a combination of single-molecule long reads and the more conventional short reads are generated from Rhizophora apiculata for the de novo assembly of its genome to a near chromosome level. The longest scaffold, N50 and N90 for the R. apiculata genome, are 13.3 Mb, 5.4 Mb and 1.0 Mb, respectively. Short reads for the genomes and transcriptomes of eight related species are also generated. We find that the ancestor of Rhizophoreae experienced a whole-genome duplication ~70 Myrs ago, which is followed rather quickly by colonization and species diversification. Mangroves exhibit pan-exome modifications of amino acid(AA) usage as well as unusual AA substitutions among closely related species. The usage and substitution of AAs, unique among plants surveyed, is correlated with the rapid evolution of proteins in mangroves. A small subset of these substitutions is associated with mangroves' highly specialized traits(vivipary and red bark) thought to be adaptive in the intertidal habitats. Despite the many adaptive features, mangroves are among the least genetically diverse plants, likely the result of continual habitat turnovers caused by repeated rises and falls of sea level in the geologically recent past. Mangrove genomes thus inform about their past evolutionary success as well as portend a possibly difficult future. | Shaohua Xu Ziwen He Zhang Zhang Zixiao Guo Wuxia Guo Haomin Lyu Jianfang Li Ming Yang Zhenglin Du Yelin Huang Renchao Zhou Cairong Zhong David E. Boufford Manuel Lerdau Chung-I Wu Norman C. Duke Suhua Shi | 2017 | National Science Review2017,4,5: | 7 |
| 14 | β-MnO_(2) with proton conversion mechanism in rechargeable zinc ion battery显示文摘Rechargeable aqueous zinc ion battery(RAZIB)is a promising energy storage system due to its high safety,and high capacity.Among them,manganese oxides with low cost and low toxicity have drawn much attention.However,the under-debate proton reaction mechanism and unsatisfactory electrochemical performance limit their applications.Nanorod b-MnO_(2) synthesized by hydrothermal method is used to investigate the reaction mechanism.As cathode materials for RAZIB,the Zn//b-MnO_(2) delivers 355 mA h g^(-1)(based on cathode mass)at0.1 A g^(-1),and retain 110 mA h g^(-1) after 1000 cycles at 0.2 A g^(-1).Different from conventional zinc ion insertion/extraction mechanism,the proton conversion and Mn ion dissolution/deposition mechanism of b-MnO_(2) is proposed by analyzing the evolution of phase,structure,morphology,and element of b-MnO_(2) electrode,the pH change of electrolyte and the determination of intermediate phase MnO OH.Zinc ion,as a kind of Lewis acid,also provides protons through the formation of ZHS in the proton reaction process.This study of reaction mechanism provides a new perspective for the development of Zn//MnO_(2) battery chemistry. | Wenbao Liu Xiaoyu Zhang Yongfeng Huang Baozheng Jiang Ziwen Chang Chengjun Xu Feiyu Kang | 2021 | Journal of Energy Chemistry2021,30,5: | 6 |
| 15 | Fenton-like degradation of Methylene Blue using paper mill sludge-derived magnetically separable heterogeneous catalyst:Characterization and mechanism显示文摘For the paper industry, the disposal and management of the yielded sludge are a considerable challenge. In our work, the paper mill sludge-derived magnetically separable heterogeneous catalyst(PMS-Fe-380) was prepared easily through a facile synthesis method. The morphology and structure of PMS-Fe-380 were fully characterized by means of X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and Brunauer–Emmet–Teller analysis. The catalytic activity of PMS-Fe-380 was evaluated by degradation of Methylene Blue(MB). The reusability and stability of PMS-Fe-380 were evaluated in five repeated runs, which suggested that PMS-Fe-380 manifested excellent stability of catalytic activity. Moreover,leaching tests indicated that the leached iron is negligible(<0.5 mg/L). This study provides an alternative environmentally friendly reuse method for paper mill sludge and a novel catalyst PMS-Fe-380 that can be considered as a promising heterogeneous Fenton-like catalyst. | Guoqiang Zhou Ziwen Chen Fei Fang Yuefeng He Haili Sun Huixiang Shi | 2015 | Journal of Environmental Sciences2015,27,9: | 6 |
| 16 | Relaxation study of cement based grouting material using nuclear magnetic resonance显示文摘Aiming at actual condition of poor effect of hole sealing for the reason of poor cement paste fluidity in the process of coal mine gas drainage,by adding a water reducing agent,cement paste for hole sealing was produced.The changes of initial distribution,weighted average values and total relaxation signal intensity of transverse relaxation time(T 2) of water in pure cement paste and water reducing agent added cement paste were studied with low field proton nuclear magnetic resonance(NMR).The results show that there are four peaks in T2 distribution curves of cement paste:the first peak is related to the bound water in flocculation,the second and the third peaks are related to the water in flocculation,water reducing agent makes it extending towards the long relaxation time,increasing its liquidity,and the fourth peak is related to the free water.By using weighted average values of T2 and total relaxation signal intensity,hydration process of cement pastes could be roughly divided into four stages:the initial period,reaction period,accelerated period and steady period.By analyzing the periods,it makes sure that the grouting process should be completed in the reaction period in the site,and the drainage process should be started in the steady period.The results have great guiding significance to the hole sealing and methane drainage. | Li Xianzhong Lin Baiquan Zhai Cheng Ni Guanhua Li Ziwen | 2012 | International Journal of Mining Science and Technology2012,22,6: | 6 |
| 17 | Quantifying urbanization levels on the Tibetan Plateau with high-resolution nighttime light data显示文摘The Tibetan Plateau(TP)is undergoing rapid urbanization.To improve urban sustainability and construct eco-logical security barriers,it is essential to quantify the spatial patterns of urbanization level on the TP,but the existing studies on the topic have been limited by the lack of socioeconomic data.This study aims to quantify the urbanization level on the TP in 2018 with Luojia1-01(LJ1-01)high-resolution nighttime light(NTL)data.Specifically,the compounded night light index is used to quantify spatial patterns of urbanization level at mul-tiple scales.The results showed that the TP had a low overall urbanization level with a large internal difference.The urbanization level in the northeast,southeast and south of the TP was relatively high,forming three hotspots centered in Xining City,Lhasa City and Shangri-La City,while the urbanization level in the central and western regions was relatively low.The analysis of influencing factors,based on the random forest model,showed that transportation and topography were the main factors affecting the TP’s spatial patterns of urbanization level.The comparison analysis with socioeconomic statistics and traditional NTL data showed that LJ1-01 NTL data can be used to more effectively quantify the urbanization level since it is more advantageous for reflecting the spatial extent of urban land and describing the spatial structure of socioeconomic activities within urban areas.These advantages are attributed to the high spatial resolution of the data,appropriate imaging time and unaf-fected by saturation phenomena.Thus,the proposed LJ1-01 NTL-based urbanization level measurement method has the potential for wide applications around the world,especially in less-developed regions lacking statistical data.Using this method,we refined the measurement of the TP’s urbanization level in 2018 for multiple scales including the region,basin,prefecture and county levels,which provides basic information for the further urban sustainability research on the TP. | Yihang Wang Zhifeng Liu Chunyang He Pei Xia Ziwen Liu Haimeng Liu | 2020 | Geography and Sustainability2020,1,3: | 5 |
| 18 | Crop positioning for robotic intra-row weeding based on machine vision显示文摘A machine-vision-based method of locating crops is described in this research.This method was used to provide real-time positional information of crop plants for a mechanical intra-row weeding robot.Within the normalized red,green,and blue chromatic coordinates(rgb),a modified excess green feature(g-r>T&g-b>T)was used to segment plant material from back ground in color images.The threshold T was automatically selected by the maximum variance(OTSU)algorithm to cope with variable natural light.Taking into account the geometry of the camera arrangement and the crop row spacing,the target regions covering the crop rows were defined based on a pinhole camera model.According to the statistical variation in the pixel histogram in each target region,locations of the crop plants were initially estimated.To obtain the accurate locations of crops,median filtering was conducted locally in the bounding boxes of the crops close to the bottom of the images.For the lateral guidance of the robot,a novel method of calculating lateral offset was proposed based on a simplified match between a template and the detected crops.Field experiments were conducted under three different illumination conditions.The results showed that the accurate identification rates on lettuce,cauliflower and maize were all above 95%.The positional error as within±15 mm,and the average processing time for a 640×480 image was 31 ms.The method was adequate to meet the technical requirement of the weeding robot,and laid a foundation for robotic weeding in commercial production system. | Li Nan Zhang Chunlong Chen Ziwen Ma Zenghong Sun Zhe Yuan Ting Li Wei Zhang Junxiong | 2015 | International Journal of Agricultural and Biological Engineering2015,8,6: | 4 |
| 19 | Effect of potential HONO sources on peroxyacetyl nitrate(PAN)formation in eastern China in winter显示文摘As an important secondary photochemical pollutant,peroxyacetyl nitrate(PAN)has been studied over decades,yet its simulations usually underestimate the corresponding observations,especially in polluted areas.Recent observations in north China found unusually high concentrations of PAN during wintertime heavy haze events,but the current model still cannot reproduce the observations,and researchers speculated that nitrous acid(HONO)played a key role in PAN formation.For the first time we systematically assessed the impact of potential HONO sources on PAN formation mechanisms in eastern China using the Weather Research and Forecasting/Chemistry(WRF-Chem)model in February of 2017.The results showed that the potential HONO sources significantly improved the PAN simulations,remarkably accelerated the RO x(sum of hydroxyl,hydroperoxyl,and organic peroxy radicals)cycles,and resulted in 80%–150%enhancements of PAN near the ground in the coastal areas of eastern China and 10%–50%enhancements in the areas around 35–40°N within 3 km during a heavy haze period.The direct precursors of PAN were aldehyde and methylglyoxal,and the primary precursors of PAN were alkenes with C>3,xylenes,propene and toluene.The above results suggest that the potential HONO sources should be considered in regional and global chemical transport models when conducting PAN studies. | Jingwei Zhang Yitian Guo Yu Qu Yong Chen Ruipeng Yu Chaoyang Xue Rui Yang Qiang Zhang Xingang Liu Yujing Mu Jing Wang Can Ye Haihan Zhao Qiangqiang Sun Ziwen Wang Junling An | 2020 | Journal of Environmental Sciences2020,32,8: | 3 |
| 20 | Convergent adaptation of the genomes of woody plants at the land-sea interface显示文摘Sequencing multiple species that share the same ecological niche may be a new frontier for genomic studies.While such studies should shed light on molecular convergence,genomic-level analyses have been unsuccessful,due mainly to the absence of empirical controls.Woody plant species that colonized the global tropical coasts,collectively referred to as mangroves,are ideal for convergence studies.Here,we sequenced the genomes/transcriptomes of 16 species belonging in three major mangrove clades.To detect convergence in a large phylogeny,a CCS+model is implemented,extending the more limited CCS method(convergence at conservative sites).Using the empirical control for reference,the CCS+model reduces the noises drastically,thus permitting the identification of 73 convergent genes with Ptrue(probability of true convergence)>0.9.Products of the convergent genes tend to be on the plasma membrane associated with salinity tolerance.Importantly,convergence is more often manifested at a higher level than at amino-acid(AA)sites.Relative to>50 plant species,mangroves strongly prefer 4 AAs and avoid 5 others across the genome.AA substitutions between mangrove species strongly reflect these tendencies.In conclusion,the selection of taxa,the number of species and,in particular,the empirical control are all crucial for detecting genome-wide convergence.We believe this large study of mangroves is the first successful attempt at detecting genome-wide site convergence. | Ziwen He Shaohua Xu Zhang Zhang Wuxia Guo Haomin Lyu Cairong Zhong David EBoufford Norman CDuke The International Mangrove Consortium Suhua Shi | 2020 | National Science Review2020,7,6: | 3 |