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Microbial mediated arsenic biotransformation in wetlands

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Frontiers of Environmental Science & Engineering 2017年第1期11卷 5-15页

作者： si-Yu Zhang Paul n. Williams Jinming Luo Yong-Guan Zhu State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China State Key Joint Laboratory of Environment simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China institute for Global Food Security School of Biological Sciences Queen's University Belfast Belfast BT9 7BN UK Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Key Laboratory of Urban Environment and Health Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021 China

Arsenic （As） is a pervasive environmental toxin and carcinogenic metalloid. it ranks at the top of the US priority List of Hazardous Substances and causes worldwide human health problems. Wetlands, including natural and artificial ecosystems （i.e. paddy soils） are highly susceptible to As enrichment; acting not only as repositories for water but a host of other elemental/chemical moieties. While macroscale processes （physical and geological） supply As to wetlands, it is the micro-scale biogeochemistry that regulates the fluxes of As and other trace elements from the semi-terrestrial to neighboring plant/ aquatic/atmospheric compartments. Among these fine-scale events, microbial mediated As biotransformations contribute most to the element＇s changing forms, acting as the ＇switch＇ in defining a wetland as either a source or sink of As. Much of our understanding of these important microbial catalyzed reactions follows relatively recent scientific discoveries. Here we document some of these key advances, with focuses on the implications that wetlands and their microbial mediated transformation pathways have on the global As cycle, the chemistries of microbial mediated As oxidation, reduction and methylation, and future research priorities areas.

关键词： Arsenic Wetland Microbes Switch

Anthropogenic Pseudokarstic Depressions on Mount Bocskor(Bakony Region, Hungary)

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Journal of Earth Science 2023年第1期34卷 214-231页

作者： Márton Veress Zoltán Unger Szilárd Vetési-Foith Department of Geography Savaria University centreEötvös Lóránd UniversitySzombathely9700Hungary institute of Geography University of PécsPécs7600Hungary

Surface forms above the mine(ármin mine) of Mount Bocskor(Southern Bakony, Hungary) were examined. We made contour maps, plan maps, morphological maps and atectonic grike(cave) maps of some of the forms and their surroundings. We examined the distribution of the depth, length, elongation ratio in case of some depressions, the relation between the depth and the diameter of some depressions, the relationship between depression group directions and mine cut directions, the standard deviation of the direction differences of depression groups and of their depressions. The forms of the mountain related to surface mining can be separated to open and closed. The former are trenches and stairs, the latter are circular, elongated, and complex depressions. The formation of these forms can be related to the balancing movements of the vault over the mountain’s mine. At thin vault, stairs develop by collapses, while at the atectonic fissures of thicker vault, trenches and depressions are formed at the surface. in areas bordered by sinking(subsidence through) and downwardly cohesive faults, depression groups of diverse features are arranged in the marginal bands. Elongated depressions are formed at atectonic blocks bounded by dispersing faults in non-banded distribution. Where there is a superficial deposit, atectonic fissures can also be inherited directly by collapse to the surface and form depressions. They can also form indirectly over atectonic fissures by compaction, subsequent collapse and/or suffosion of the superficial deposit. The results of the study make it possible to analyse the material loss due to mining on the vault if the atectonic structures of the vault are partly or completely covered by superficial deposit.

关键词： mining pseudokarstic depression atectonic fissure atectonic block collapse suffosion

EXPECTED nUMBER OF iTERATiOnS OF inTERiOR-POinT ALGORiTHMS FOR LinEAR PROGRAMMinG

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Journal of Computational Mathematics 2005年第1期23卷 93-100页

作者： si-mingHuang instituteofPolicyandManagement ChineseAcademyofScienceBeijing100080China

We study the behavior of some polynomial interior-point algorithms for solving random linear programming (LP) problems. We show that the expected and anticipated number of iterations of theseTodd's probabilisticalgori... 详细信息

关键词： linear programming Lnterior point algorithms probabilistic LP models expected number of iterations

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通过炎性因子曲线探讨血液透析的临床预后

罕少疾病杂志 2025年第1期32卷 156-158页

作者：徐思涵南阳医学高等专科学校第一附属医院检验科河南南阳473000

目的通过炎性因子[白细胞介素-6(iL-6)、C反应蛋白(CRP)、降钙素原(Pct)]曲线探讨血液透析的临床预后。方法采取回顾性研究,选择2023年1月至2023年12月医院收治120例完成1年随访的MHD患者作为研究对象。根据患者预后情况,将随访1年内... 详细信息

目的通过炎性因子[白细胞介素-6(iL-6)、C反应蛋白(CRP)、降钙素原(Pct)]曲线探讨血液透析的临床预后。方法采取回顾性研究,选择2023年1月至2023年12月医院收治120例完成1年随访的MHD患者作为研究对象。根据患者预后情况,将随访1年内病死患者纳入预后不良组(n=31),将存活患者纳入预后良好组(n=89)。统计并比较两组基线资料、炎症因子(iL-6、CRP、Pct)水平;采用Cox回归分析检验影响MHD患者预后不良的的影响因素;采用受试者工作特征曲线(ROC)曲线预测血清iL-6、CRP及Pct水平对MHD患者预后不良的预测价值;采用R4.1.3统计学软件,绘制血清iL-6、CRP及Pct水平预测MHD患者预后不良的决策曲线。结果预后不良组透析龄长于预后良好组,营养不良占比高于预后良好组,血清iL-6、CRP及Pct水平高于预后良好组(PiL-6、CRP、Pct、透析龄、营养不良是影响MHD患者预后不良的独立危险因素(HR>1,PiL-6、CRP、Pct水平及联合检查预测MHD患者预后不良的AUC均>0.70,具有一定的预测价值,且三者联合预测价值最高;绘制决策曲线,结果显示,在阈值0.000~0.446、0.658~1.000范围内,血清iL-6、CRP、Pct水平联合预测MHD患者预后不良净收益率优于单独的净收益率。结论血清iL-6、CRP及Pct水平是MHD患者预后不良的独立危险因素,联合检测预测效能最高,可用于预测MHD患者预后。

关键词：维持性血液透析预后白细胞介素-6 C反应蛋白降钙素原

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Path Factors and neighborhoods of independent Sets in Graphs

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Acta Mathematicae Applicatae sinica 2023年第2期39卷 232-238页

作者： si-zhong ZHOU School of Science Jiangsu University of Science and TechnologyZhenjiang 212100China

A path-factor is a spanning subgraph F of G such that every component of F is a path with at least two *** k≥2 be an integer.A P_(≥k)-factor of G means a path factor in which each component is a path with at least k vertices.A graph G is a P_(≥k)-factor covered graph if for any e∈E(G),G has a P_(≥k)-factor including ***βbe a real number with 1/3≤β≤1 and k be a positive *** verify that(ⅰ)a k-connected graph G of order n with n≥5k+2 has a P_(≥3)-factor if|nG(i)|>β(n-3k-1)+k for every independent set i of G with|i|=「β(2k+1)」;(ⅱ)a(k+1)-connected graph G of order n with n≥5k+2 is a P_(≥3)-factor covered graph if|nG(i)|>β(n-3k-1)+k+1 for every independent set i of G with|i|=「β(2k+1)」.

关键词： graph independent set neighborhood P≥3-factor P≥3-factor covered graph

Binding numbers for Fractional iD-k-factor-critical Graphs

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Acta Mathematica sinica,English Series 2014年第1期30卷 181-186页

作者： si Zhong ZHOU School of Mathematics and Physics Jiangsu University of Science and Technology

LetG be a graph,and k≥2 be a positive integer.A graph G is fractional independentset-deletable k-factor-critical（in short,fractional iD-k-factor-critical）,if G i has a fractional k-factor for every independent set i of *** binding number bind（G）of a graph G is defined as bind（G）=min｜nG（X）｜｜X｜：=X V（G）,nG（X）=V（G）.in this paper,it is proved that a graph G is fractional iD-k-factor-critical if n≥6k 9 and bind（G）〉（3k 1）（n 1）kn 2k＋2.

关键词： Graph binding number independent set fractionalk-factor fractional iD-k-factor-criti-cal

Degeneracy and Finiteness Theorems for Meromorphic Mappings in Several Complex Variables

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Chinese Annals of Mathematics,Series B 2019年第2期40卷 251-272页

作者： si Duc QUAnG Department of Mathematics Hanoi National University of Education Thang Long institute of Mathematics and Applied Sciences

The author proves that there are at most two meromorphic mappings of C^m into P^n(C)(n ≥ 2) sharing 2 n+ 2 hyperplanes in general position regardless of multiplicity,where all zeros with multiplicities more than certain values do not need to be counted. He also shows that if three meromorphic mappings f^1, f^2, f^3 of Cminto P^n(C)(n ≥ 5) share2 n+1 hyperplanes in general position with truncated multiplicity, then the map f^1×f^2×f^3 is linearly degenerate.

关键词： Second main theorem Uniqueness problem Meromorphic mapping Multiplicity

A new inclination-based method to evaluate the global geomagnetic configuration and axial dipole moment

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Earth and Planetary Physics 2022年第4期6卷 359-365页

作者： KaiHua Xu Fei He Yong Wei Ross n.Mitchell si Chen YuQi Wang ZhaoJin Rong Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China School of Earth and Environment University of LeedsLeedsLS29JTUK

The strength and configuration of the geomagnetic field control the average shape of the *** pure dipole assumption and the virtual dipole moment(VDM),determined by individual records,have been widely adopted to evaluate the strength of the geomagnetic field in geological ***,such an assumption might not be valid during geomagnetic transitions,such as reversals and *** traditional spherical harmonic modeling of the geomagnetic field could be difficult to implement because accurate global records are ***,we report that an empirical relationship exists between the ratio of the VDM to the true axial dipole moment(VDM/ADM)and the ratio of the power of the axial dipole to that of the non-axial dipole(AD/nAD)based on a new method utilizing globally distributed inclination *** root mean square global deviation of inclination(RMSΔi)to the standard inclination distribution of the AD was fitted to the AD/nAD with a cubic polynomial by utilizing a large number of geodynamo *** with geomagnetic field models showed that the AD/nAD derived from the RMSΔi agreed well with that calculated by using the Gauss coefficients,and the estimated ADM was consistent with the true ***,the application of volcanic records during the Laschamp excursion showed the VDM might overestimate the ADM by a factor of *** new method will be useful in future studies that characterize the configuration of the geomagnetic field and the strength of the axial dipole.

关键词： axial dipole magnetic inclination virtual dipole moment

Degree Conditions for k-Hamiltonian[a,b]-factors

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Acta Mathematicae Applicatae sinica 2021年第2期37卷 232-239页

作者： Jie WU si-zhong ZHOU School of Economic and management Jiangsu University of Science and TechnologyZhenjiang 212100China School of Science Jiangsu University of Science and TechnologyZhenjiang 212100China

Let a,b,k be nonnegative integers with 2≤ais called a k-Hamiltonian graph if G-U contains a Hamiltonian cycle for any subset U?V(G)with|U|=***[a,b]-factor F of G is called a Hamiltonian[a,b]-factor if F contains a Hamiltonian *** G-U admits a Hamiltonian[a,b]-factor for any subset U?V(G)with|U|=k,then we say that G has a k-Hamiltonian[a,b]-*** that G is a k-Hamiltonian graph of order n with n≥((a+b-4)(2 a+b+k-6))/(b-2)+k andδ(G)≥a+*** this paper,it is proved that G admits a k-Hamiltonian[a,b]-factor if max{dG(x),dG(y)}≥((a-2)n+(b-2)k)/(a+b-4)+2 for each pair of nonadjacent vertices x and y in G.

关键词： degree condition k-Hamiltonian graph k-Hamiltonian[a b]-factor