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Quantifying the carbon source of pedogenic calcite veins in weathered limestone: implications for the terrestrial carbon cycle

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Acta Geochimica 2019年第4期38卷 481-496页

作者： Lin Zou Lin Dong Meng Ning Kangjun Huang Yongbo Peng Shujian Qin Honglin Yuan Bing Shen Key Laboratory of Orogenic Belts and Crustal Evolution MOE and School of Earth and Space SciencePeking UniversityBeijingPeople's Republic of China Shaanxi Key Laboratory of Early Life and Environments Department of GeologyNorthwest UniversityXi'anPeople's Republic of China Department of Geology and Geophysics Louisiana State UniversityBaton RougeLA 70803USA

The continent is the second largest carbon sink on Earth’s surface.With the diversification of vascular land plants in the late Paleozoic,terrestrial organic carbon burial is represented by massive coal formation,while the development of soil profiles would account for both organic and inorganic carbon burial.As compared with soil organic carbon,inorganic carbon burial,collectively known as the soil carbonate,would have a greater impact on the long-term carbon cycle.Soil carbonate would have multiple carbon sources,including dissolution of host calcareous rocks,dissolved inorganic carbon from freshwater,and oxidation of organic matter,but the host calcareous rock dissolution would not cause atmospheric CO2drawdown.Thus,to evaluate the potential effect of soil carbonate formation on the atmospheric p CO2level,different carbon sources of soil carbonate should be quantitatively differentiated.In this study,we analyzed the carbon and magnesium isotopes of pedogenic calcite veins developed in a heavily weathered outcrop,consisting of limestone of the early Paleogene Guanzhuang Group in North China.Based on the C and Mg isotope data,we developed a numerical model to quantify the carbon source of calcite veins.The modeling results indicate that4–37 wt%of carbon in these calcite veins was derived from atmospheric CO2.The low contribution from atmospheric CO2might be attributed to the host limestone that might have diluted the atmospheric CO2sink.Nevertheless,taking this value into consideration,it is estimated that soil carbonate formation would lower 1 ppm atmospheric CO2within 2000 years,i.e.,soil carbonate alone would sequester all atmospheric CO2within 1 million years.Finally,our study suggests the C–Mg isotope system might be a better tool in quantifying the carbon source of soil carbonate.

关键词： Mg isotope Calcite veins Pedogenic carbonate Silicate weathering Carbonate weathering

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Application of Calcite veins to Study of Newly-activated Faulting

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Science China Chemistry 1994年第5期37卷 613-624页

作者：刘行松史兰斌唐汉军林传勇何永年 Institute of Geology State Seismological Bureau Beijing 100029 PRC

The study of period and chronology of fault activity in major worksites in an area with exposed basement rocks is quite difficult. The authors have applied the combinative techniques of field investigation, microscopic observation and isotopic dating to studying the calcite veins filled in the fault zones in several major engineering regions and got successful results. The following conclusions are reached: (i) The last period of strong activity of fault F8 in the Tianshengqiao Hydropower Station, Nanpan River is 200 ka B. P. , and there has been, no obvious activity since 150 ka. (ii) The last period of strong activity for 5 faults in Shixiali Reservoir, Yangyuan County, Hebei Province is 200-300 ka B. P. , and there has been no obvious activity since 200 ka. The research results provide a sound basis of engineering geology for project designers.

关键词： new activity of fault calcite veins period of faulting stress field dating of faulting.

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Sand veins and MISS from the Mesoproterozoic black shale (ca. 1.7 Ga) in North China:Implication for methane degassing from microbial mats

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Science China Earth Sciences 2008年第11期51卷 1525-1536页

作者： SHI XiaoYing JIANG GanQing ZHANG ChuanHeng GAO LinZhi LIU Juan School of Earth Science and Resources China University of GeosciciencesBeijing 100083China State Key Laboratory of Geological Process and Mineral Resources Beijing 100083China Department of Geoscience University of NevadaLas VegasNV 89154-4010USA Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

The Mesoproterozoic Chuanlinggou Formation (ca. 1.7 Ga) consists mainly of dark-gray to black shales that are widespread in the North China Platform. Abundant centimeter-scale sand veins are present within the shale layers of this unit, particularly in the middle part. Sand veins display ptygmatic shapes, perpendicular or with a high angle to bedding planes. They penetrate the black shale layers but are often terminated by thin, lenticular sandstone beds, forming small-scale ‘tepee-like’ structures. On bedding planes, sand veins are expressed as small ridges with 1–3 mm positive relief. Lack of polygonal shapes and their occurrence in thinly laminated, relatively deep-water shales preclude an origin from sand-filled desiccation cracks. Instead, their close association with microbially induced sedimentary structures (MISS) such as micro-wrinkles and gas blisters, putative bacterial fossils (possibly coccoidal cyanobacteria) and framboidal pyrites, suggests that they were formed by degassing of methane from microbial mat decay. Methane gas disrupted overlying sedimentary layers, creating fractures open to seawater. Fine-grained quartz sands, which were transported into the depositional environment by strong winds, filled the fractures. Sand-filled fractures were shortened and folded during burial compaction, forming ptygmatic shapes. The presence of dispersed dolomite and siderite in these sand veins suggests authigenic carbonate precipitation from anaerobic oxidation of methane (AOM). Sand veins are intensely distributed within the Chuanlinggou Formation and are spatially widespread in the North China Platform. If their methane origin is confirmed, they may have important implications for the Mesoproterozoic paleoclimate. With anoxic oceans and low seawater sulfate concentration during the Mesoproterozoic, methane release from microbial mat decay and/or microbial methanogenesis during shallow burial may have been proportionally higher than that of the modern marine environments, with resultant increase in the rela

关键词： sand veins methane degassing microbial mats Chuanlinggou Formation Mesoproterozoic North China Platform

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Application of the Trivex system in the treatment of primary severe superficial varicose veins of the lower extremity

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Journal of Interventional Medicine 2019年第4期2卷 146-149页

作者： Wenshui Yu Jing Liu Hongwei Yang Zuhui Wang Yongdi Xia Peijuan Liu Guoxian Zhu Department of Vascular Surgery The First Affiliated Hospital of ShenZhen UniversityShenZhen No.2 HospitalShenZhen518036China Department of Interventional Radiography The First Affiliated Hospital of ShenZhen UniversityShenZhen No.2 HospitalShenZhen518036China

Purpose:The aim of this study was to evaluate the clinical effects of the Trivex system in the treatment of primary severe superficial varicose veins of the lower extremity and compare Trivex to the point-form-stripping combined with foam sclerotherapy(FS).Methods:A total of 64 patients(35 females,29 males;mean age,57?11 years[range,29–79 years])with primary severe superficial varicose veins of the lower extremity involving 64 legs were included between October 2015 and July 2019.The maximum diameter of the vein branches was>20 mm,which appeared to be cystic dilatation and forms large-scale in the crus or the thigh.All patients underwent high ligation and endovenous laser ablation or stripping of the trunk under general anesthesia.The surgical time,pain/phlebitis,number of incisions,amount of bleeding,recurrence of varicose vein,incidence of surgical site infections(SSIs),satisfaction score,and improvement in clinical symptoms were evaluated respectively with the patients in two groups:Group A,with patients who underwent treatment with the Trivex system,and Group B,patients who underwent treatment by point-form-stripping combined with FS.Results:All procedures were performed successfully.The average operative time in Group A was 56?11 min,whereas that of Group B was 90?33 min,which was a significant difference(p0.05).Conclusions:This study shows that patients benefited from both treatment options.However,primary severe superficial varicose veins of the lower extremity treated with the Trivex system suffered

关键词： Varicose veins Trivex system Point-form-stripping Foam sclerotherapy

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Twist deformation and buckling behavior of veins

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医用生物力学 2013年第S1期28卷 25-28页

作者： Justin Garcia Haichao Han The University of Texas at San Antonio Department of Mechanical Engineering/Biomedical Engineering Program

Introduction Twisted arteries and veins disrupt normal blood flow and elevate the risk for clinical complications such as thrombosis,heart attack,stroke,and organ dysfunction.veins should remain mechanically stable for normal function.However,compared to arteries,veins are more vulnerable to collapse because they are thin-walled and under lower lumen pressure.Twisted veins have been shown to occur with head turning or after inadvertent twist during various vascular surgeries.In vivo and cadaver studies have demonstrated that turning the head to one side can result in torsion and compression of the internal jugular vein and can compromise cranial drain-

关键词： veins buckling jugular arteries compromise disrupt torsion walled vulnerable torque

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Understanding Contaminant veins in Squeeze Casting and Semi-solid Metalworking Processes

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特种铸造及有色合金 2003年第Z1期23卷 230-234,238页

作者： Edward J. Vinarcik, P.E. Engineer Voctorie Co.8218 Medicine Bow Run Fort WayreIdiana 46825 U.S A

When commercializing the semi-solid metalworking processes, component producers looked to conventional die-casting to identify potential defects and control component quality. Several defects were expected including cold shuts, cold flows, flash, drags, warping, and gas entrapment, just to name a few. Efforts were taken to avoid these defects. A new defect type, contaminant veins, has surfaced unique to semi-solid metalworking. Although, semi-solid metalworking has proven to be successful, component producers have been reluctant to report defects for fear of giving this emerging processes a bad reputation. Nonetheless, this defect must be understood to avoid future problems.

关键词： Contaminant veins Squeeze Casting Semi-solid Casting

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Treatment of leg veins 2nd ed

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丛书名： Procedures in cosmetic dermatology

2011年

作者： edited by Murad Alam Sirunya Silapunt DVD editors Michael R. Migden Tri H. Nguyen.

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OBV(obscure vein),a C_(2)H_(2)zinc finger transcription factor,positively regulates chloroplast development and bundle sheath extension formation in tomato(Solanum lycopersicum)leaf veins

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Horticulture Research 2021年第1期8卷 3228-3241页

作者： Jinghua Lu Chunyang Pan Xin Li Zejun Huang Jinshuai Shu Xiaoxuan Wang Xiaoxiao Lu Feng Pan Junling Hu Hui Zhang Wenyue Su Min Zhang Yongchen Du Lei Liu Yanmei Guo Junming Li Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of Ministry of Agriculture Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing 100081China

Leaf veins play an important role in plant growth and development,and the bundle sheath(BS)is believed to greatly improve the photosynthetic efficiency of C_(4) plants.The OBV mutation in tomato(Solanum lycopersicum)results in dark veins and has been used widely in processing tomato varieties.However,physiological performance has difficulty explaining fitness in production.In this study,we confirmed that this mutation was caused by both the increased chlorophyll content and the absence of bundle sheath extension(BSE)in the veins.Using genome-wide association analysis and map-based cloning,we revealed that OBV encoded a C_(2)H_(2) L domain class transcription factor.It was localized in the nucleus and presented cell type-specific gene expression in the leaf veins.Furthermore,we verified the gene function by generating CRISPR/Cas9 knockout and overexpression mutants of the tomato gene.RNA sequencing analysis revealed that OBV was involved in regulating chloroplast development and photosynthesis,which greatly supported the change in chlorophyll content by mutation.Taken together,these findings demonstrated that OBV affected the growth and development of tomato by regulating chloroplast development in leaf veins.This study also provides a solid foundation to further decipher the mechanism of BSEs and to understand the evolution of photosynthesis in land plants.

关键词： extension (2) veins

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基于veins的交通路径优化算法研究

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信息技术 2022年第5期46卷 118-122,127页

作者：刘琨北京师范大学珠海分校广东珠海519087

智能交通系统是未来智慧城市中不可缺少的一部分,而交通路径优化是智能交通重要的组成部分。文中主要研究了在veins平台中交通路径优化算法。通过VANET(车载自组网)每台车辆都在同一个局域网互连互通,当前车遇到拥堵时通过拥塞躲避机制... 详细信息

智能交通系统是未来智慧城市中不可缺少的一部分,而交通路径优化是智能交通重要的组成部分。文中主要研究了在veins平台中交通路径优化算法。通过VANET(车载自组网)每台车辆都在同一个局域网互连互通,当前车遇到拥堵时通过拥塞躲避机制不断通知后方车辆,后方车辆通过设计的路径规划算法进行路径变更,直至拥堵结束。通过分析车辆通过的情况和交通数据,不断优化算法,最终达到减缓拥堵和提高交通效率的目的。

关键词： veins 路径规划拥塞躲避优化算法交通优化

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Shengmai Suppressed Vascular Tension in Umbilical Arteries and veins of Human and Sheep

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Pharmacology & Pharmacy 2015年第6期6卷 281-291页

作者： Xiaohui Yin Xiuxia Gu Yun He Di Zhu Jie Chen Jue Wu Xueqin Feng Jinhao Li Caiping Mao Zhice Xu Institute for Fetology & Reproductive Medicine Center First Hospital of Soochow University Suzhou China Center for Prenatal Biology Loma Linda University Loma Linda CA USA

Objective—The umbilical cord is a critical pathway between mothers and fetuses, and regulations of umbilical vessel tension are important for fetal growth. Shengmai is an herbal medicine being used in treatments of cardiovascular diseases. However, effects of Shengmai on human blood vessels and related pharmacological mechanisms are unclear. Methods—This study investigated the effects of related mechanisms of Shengmai and its key compounds on human and sheep umbilical arteries and veins using organ bath systems. Key Findings—Shengmai significantly suppressed phenylephrine-stimulated vasoconstriction in umbilical arteries and veins. NG-Nitro-L-arginine Methyl Estercould not change the Shengmai-suppressed vasoconstriction in human and sheep umbilical vessels. Among four key compounds of Shengmai, Ginsenoside Re, Ginsenoside Rb1, Ginsenoside Rg1, and Schisandrin, only Ginsenoside Re showed the significant effect similar to Shengmai’s in the umbilical vessels. In Ca2+-free solution, Ginsenoside Re did not affect vasoconstriction. In addition, caffeine- or phenylephrine-stimulated vasoconstriction were not changed by Ginsenoside Re. Either charybdotoxin or glibenclamide could inhibit Ginsenoside Re-caused inhibition of the stimulated vasoconstriction in both human and sheep umbilical vessels, where 4-aminopyridine did not show the similar inhibitory effect. Conclusion—The results provide new information on Shengmai’s effects and underlying mechanisms in umbilical vessels. Importantly, the information gained offers interesting potential for developing new drugs acting on umbilical cords for fetal medicine.

关键词： Shengmai Umbilical Arteries and veins Ginsenoside Re α-Adrenergic Receptor Vascular Tension

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