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Zinc phosphate dissolution by bacteria isolated from an oligotrophic karst cave in central China

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Frontiers of Earth Science 2013年第3期7卷 375-383页

作者： Hongmei WANG Qiang dong jianping ZHOU Xing XIANG State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences Wuhan 430074 China

Biogeochemical processes are fundamental to sustain the ecosystem in subsurface caves, but to date they are still far from well understood. To investigate micro-bially mediated phosphorus and zinc cycles, we isolated three bacterial strains from the dripping water in Heshang cave, central China, identified as Exiguobacterium aurantiacum E11, Pseudomonas fluorescens P35, and Pseu- domonas poae P41, respectively. Microbial capabilities in the dissolution of phosphorus-containing minerals were tested with zinc phosphate （Zn3（PO4）2） in batch culture at 30~C. A spectrophotometer, atomic absorption spectrum, and scanning electronic microscopy were used to measure the microbial growth, soluble Zn（II） concentration, and to observe the morphology of Zn3（PO4）2 before and after microbial dissolution. P. fluorescens and P. poae, the well- known phosphorus solubilizing bacteria （PSB）, are observed to solubilize Zn3（PO4）2 with an efficiency of 16.7% and 17.6%, respectively. To our knowledge, E. aurantiacum is firstly reported in this study to dissolve phosphorous-containing minerals with a higher efficiency of 39.7%, expanding our understanding about the ubiquitous occurrence of PSB in natural environments. Aqueous Zn（II） concentration positively correlates with H＋ activity, confirming the presence of acidification mechanisms widely exploited by PSB. Few itching pits were observed on the surface of Zn3（PO4）2 after microbial dissolution, inferring that microbial dissolution is not always associated with the direct contact with minerals. Even though the soluble Zn（II） concentration reached up to 370 mg/L in the system inoculated with E. aurantiacum Ell, inhibition of microbial growth was not detected by spectrophotometer. Our laboratory data revealed the importance of microbially-mediated P and Zn cycles in the subsurface ecosystem.

关键词： karst cave phosphate solubilizing bacteria (PSB) zinc toxicity biogeochemical process subsurface biosphere

Towards rational design in electrochemical denitrification by analyzing pH dependence

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National Science Review 2024年第6期11卷 223-232页

作者： Huan Li dong Luan Jun Long Xiaoyan Fu jianping Xiao State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

A small fraction of NOx（<1%） always exists in CO2feedstock（e.g. exhausted gas）, which can significantly reduce the efficiency of CO2electroreduction by ～30%. Hence, electrochemical denitrification is the precondition of CO2electroreduction. The pH effect is a key factor, and can be used to tune the selectivity between N2and N2O production in electrochemical denitrification. However, there has been much controversy for many years about the origin of pH dependence in electrocatalysis. To this end, we present a new scheme to accurately model the pH dependence of the electrochemical mechanism. An extremely small pH variation from pH 12.7 to pH 14 can be accurately reproduced for N2O production. More importantly,the obviously different pH dependence of N2production, compared to N2O, can be attributed to a cascade path. In other words, the N2was produced from the secondary conversion of the as-produced N2O molecule（the major product）, instead of the original reactant NO. This is further supported by more than 35 experiments over varying catalysts（Fe, Ni, Pd, Cu, Co, Pt and Ag）, partial pressures（20%, 50% and100%） and potentials（from -0.2 to 0.2 V vs. reversible hydrogen electrode）. All in all, the insights herein overturn long-lasting views in the field of NO electroreduction and suggest that rational design should steer away from catalyst engineering toward reactor optimization.

关键词： electrocatalysis denitrification pH-dependence nitric oxide reduction reaction mechanism

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典型遥感降水产品的水文模拟性能评估

遥感学报 2024年第2期28卷 398-413页

作者：李艳忠星寅聪庄稼成杨泽龙赵紫春李超凡王启素谢雨初王洁董剑萍林彬徐兴祝南京信息工程大学水文与水资源工程学院南京210044 南京信息工程大学水利部水文气象灾害机理与预警重点实验室南京210044 中国科学院地理科学与资源研究所北京100101 南京信息工程大学地理科学学院南京210044 宁夏吴忠市盐池县水务局吴忠751500 山东省第七地质矿产勘查院临沂276000 山东省临沂市自然资源和规划局临沂276037

遥感降水具备大尺度、近实时、高精度等优点,现已被广泛应用于流域水资源评估和生态环境保护的研究。但遥感降水产品众多,性能差异较大,不同产品在特定流域的适用性需要进行综合评估。本研究以渭河流域的4个子流域为研究区,以国家气象局... 详细信息

遥感降水具备大尺度、近实时、高精度等优点,现已被广泛应用于流域水资源评估和生态环境保护的研究。但遥感降水产品众多,性能差异较大,不同产品在特定流域的适用性需要进行综合评估。本研究以渭河流域的4个子流域为研究区,以国家气象局(CMA)逐日降水格点数据集为标准,借助ABCD水文模型,评估了5种典型的遥感降水产品(CHIRPS v2.0,CMORPH v1.0,PERSIANN-CDR,TRMM,MSWEP v2.0)对降水等级和水文过程模拟的性能。(1)在捕捉降水的时空变化格局方面,TRMM产品表现出较好的性能;(2)在基本统计指标和分类统计指标方面,多源集成产品MSWEP明显优于其他4种产品;但各遥感产品对中雨和大雨,尤其是大雨的预测效果欠佳;(3)在径流模拟方面,以TRMM降水作为输入时,ABCD模型模拟径流的效果明显优于其他遥感产品,其NSE在渭河上游、泾河上游、马莲河和北洛河分别达到了0.66、0.46、0.56和0.55。TRMM产品在捕捉降水空间格局和径流模拟方面优越,而MSWEP的统计性能较为优越。本文的研究结果,可为半干旱半湿润区域水文和气象等应用研究,在遥感降水数据源的选择方面提供科学参考依据,还可为黄河流域生态保护和高质量发展提供数据支撑。

关键词：遥感降水渭河流域 ABCD模型性能评估 MSWEP

Detection of SARS-CoV-2 Antibodies in Oral Fluid Using a Magnetic Particle-Based Chemiluminescence Immunoassay-Beijing Municipality,China,2021

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China CDC weekly 2022年第40期4卷 890-894页

作者： Naiying Mao Mei dong Zhen Zhu Qi Huang Xiali Yu Hui Xie jianping dong Jingyi Sun Fang Huang Wenbo Xu NHC Key Laboratory of Medical Virology and Viral Diseases WHO WPRO Regional Reference Laboratory of Measles and RubellaMeasles Laboratory in National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Institute for Immunization and Prevention Beijing Center for Disease Control and PreventionBeijing Academy for Preventive MedicineBeijing Institute of Tuberculosis Control Research and PreventionBeijingChina Department of Infectious Diseases Beijing Haidian HospitalBeijing Haidian Section of Peking University Third HospitalBeijingChina

Introduction:Oral fluids(OFs)have been broadly used as non-invasive samples for evaluating protective IgG antibodies from natural infection or vaccination,especially in pediatric ***:Paired OF and serum were collected from both individuals who received a booster dose of the inactive coronavirus disease 2019(COVID-19)vaccine as well as those who did not have a history of COVID-19 vaccination and infection(as the control group).The total human IgG antibody(HIgG)content was evaluated as a marker of OF sampling *** in-house adapted magnetic particle-based chemiluminescence immunoassay was used for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)IgG antibody detection in the *** SARS-CoV-2 IgG antibody in the serum samples was detected using a commercial ***:In total,579 paired OF and serum samples were *** additional 172 OF samples were collected from preschool *** results indicated that the HIgG concentration in qualified OF samples should be higher than 0.3μg/*** to the serum assay,the in-house OF immunoassay for detecting IgG antibodies against SARS-CoV-2 had 95.06%accuracy,95.03%sensitivity,and 100%***:Overall,the in-house immunoassay for detecting SARS-CoV-2 IgG antibodies in OF showed high potential for application towards serological surveillance and immunization effect assessment after large-scale,inactive COVID-19 vaccination in China.

关键词： vaccination protective specificity

Assessing Likelihood of Having False Positives Caused by Population Stratification

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Open Journal of Genetics 2019年第1期9卷 15-29页

作者： Renfang Jiang jianping dong Department of Mathematical Sciences Michigan Technological University Houghton USA

Population stratification is always a concern in association analysis. There is a debate on the extent of the problem in less extreme situations (Thomas and Witte [1], Wacholder et al. [2]). Wacholder et al. [3] and Ardlie et al. [4] showed that hidden population structure is not a serious threat to case-control designs. We propose a method of assessing the seriousness of the population stratification before designing association studies. If population stratification is not a serious problem, one may consider using case-control study instead of family-based design to get more power. In a case-control design, we compare chi-square statistics from a structured population (a union of two subpopulations) and a homogeneous population with the same prevalence and allele frequencies. We provide an explicit formula to calculate the chi-square statistics from 17 parameters, such as proportions of subpopulation, allele frequencies in subpopulations, etc. We choose these factors because they have potential to cause false associations. Each parameter takes a random value in a chosen range. We then calculate the likelihood of getting opposite conclusions in the structured and the homogeneous populations. This is the likelihood of having false positives caused by population stratification. The advantage of this method is to provide a cost effective way to choose between using case-control data and using family data before actually collecting those data. We conclude that sample sizes have a significant effect on the likelihood of false positive caused by population stratification. The larger the sample size is, the more likely to have false positive if the population structure is ignored. If the sample size will be smaller than 200 by budget constraints, then case-control study may be a better choice because of its power.

关键词： Population Stratification Case-Control Studies Linkage Disequilibrium Genome-Wide Association Studies

An Adaptive Weighted Sum Test for Family-Based Multi-Marker Association Studies

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Open Journal of Genetics 2016年第4期6卷 61-73页

作者： Renfang Jiang jianping dong Yilin Dai Department of Mathematical Sciences Michigan Technological University Houghton USA

Backgrounds: Although many disease-associated common variants have been discovered through genome-wide association studies, much of the genetic effects of complex diseases have not been explained. Population-based association studies are vulnerable to population stratification. A possible solution is to use family-based tests. However, if tests only estimate the genetic effect from the within-family variation to avoid population stratification, they may ignore the useful genetic information from between-family variation and lose power. Methods: We have developed an adaptive weighted sum test for family-based association studies. The new test uses data driven weights to combine two test statistics, and the weights measure the strength of population stratification. When population stratification is strong, the proposed test will automatically put more weight on one statistic derived from within-family variation to maintain robustness against spurious positives. On the other hand, when the effect of population stratification is relatively weak, the proposed test will automatically put more weight on the other statistic derived from both within-family and between-family variation to make use of both sources of genetic variation;and at the same time, the degrees of freedom of the test will be reduced and power of the test will be increased. Results: In our study, the proposed method achieves a higher power in most scenarios of linkage disequilibrium structure as well as Hap Map data from different genes under different population structures while still keeping its robustness against population stratification.

关键词： Family Data Genetic Association Study Population Stratification

ON AVOIDING ASSOCIATION PARADOXES INCONTINGENCY TABLES

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Systems Science and Mathematical Sciences 1998年第3期11卷 272-279页

作者： dong jianping(Department of Mathematical Sciences, Michigan Technological University,Houghton, MI 49931, U.S.A.) Michigan Technological University 美国

This article is concerned with paradoxes in 2×2×n contingency tables, suchas Simpson’s paradox, in which the association in the 2 × 2 marginal table is quite different from the associations in the 2 × 2 partial tables. We prove that if the relative number of observations in each row of each partial table or in each column of each partial table is constant, then Simpson’s paradox cannot occur. We also prove that under a certain condition, the paradox cannot occur if the odds ratios in the partial tables are uniformly greater than a lower bound (e.g. ＞ 1.125) or uniformly less than some upper ***, we show that Simpson’s paradox and an amalgamation paradox cannot occur if certain ratios of cell counts are constant in the partial tables.

关键词： Categorical data Simpson’s paradox odds ratio relative risk collapsibility

Acidic electroreduction CO_(2)to formic acid via interfacial modification of Bi nanoparticles at industrial-level current

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Nano Research 2024年第7期17卷 5817-5825页

作者： Tian dong Hongdong Li Zhenhui Wang Yanling Geng Rui Chang Xiaofeng Tian jianping Lai Shouhua Feng Lei Wang Key Laboratory of Eco-Chemical Engineering International Science and Technology Cooperation Base of Eco-Chemical Engineering and Green ManufacturingCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Shandong Engineering Research Center for Marine Environment Corrosion and Safety Protection College of Environment and Safety EngineeringQingdao University of Science and TechnologyQingdao 266042China

Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)in acidic media is a promising approach to overcome the unavoidable formation of carbonates in alkaline or neutral ***,the proton-rich environment near the catalyst surface favors hydrogen evolution reactions(HER),leading to lower energy efficiency of the desired products,especially in industrial-level current ***,quaternary ammonium cationic surfactant(cetyltrimethylammonium bromide(CTAB))was introduced into acidic electrolyte to modulate the interfacial microenvironment,which greatly enhanced CO_(2)electroreduction to formic acid(HCOOH)at the Bi/C nanoparticles *** a Bi/C nanoparticles electrode with CTAB added,constant production of formic acid was enabled with a cathodic energy efficiency of>40%and maximum FE_(HCOOH)(FE=Faradaic efficiency)of 86.2%at−400 mA·cm^(−2)over 24 *** with in-situ attenuated total reflection Fourier transform infrared spectroscopy,the concentration of*OCHO intermediates significantly increased after CTAB modification,confirming that the hydrophobic interface microenvironment formed by dynamic adsorption of positively charged long alkyl chains on Bi/C nanoparticle electrodes inhibited HER and improved the selectivity of CO_(2)RR to HCOOH.

关键词： acidic media CO_(2)electrolysis electrolyte additive hydrophobic interfacial microenvironment industrial-level current

Evaluation of the efficacy and safety of hydroxychloroquine in comparison with chloroquine in moderate and severe patients with COVID-19

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Science China(Life Sciences) 2021年第4期64卷 660-663页

作者： Qiuyu Li Cheng Cui Fei Xu jianping Zhao Nan Li Haichao Li Tianbing Wang Hua Zhang Na Liu Yudong Wei Xiaoye Niu Yan Xu jianping dong Xueting Yao Xiaohong Wang Yahong Chen Haiyan Li Chunli Song Jie Qiao dongyang Liu Ning Shen Department of Respiratory and Critical Care Medicine Peking University Third HospitalBeijing 100191China Drug Clinical Trial Center Peking University Third HospitalBeijing 100191China Deparment of Respiratory and Critical Care Medicine the First Afiliated Hospital of Nanchang UniversirNanchang 300060 China Department of Respiratory and Critical Care Medicine Tongi HospitalTongii Medical CollegeHuazhong Universiy of Science and TechnologyWuhan 430030China Research Center of Clinical Epidemiology Peking University Third HospitalBejing 100191China Department of Respiratory and Critical Care Medicine Peking University First HospitalBeijing 100034China Trauma Center Peking University People's HospitalBeijing 100044China Beijing Haidian Hospital Haidian Section of Peking University Third HospitalBeijing 100080Chima Deparment of Cardiology Peking University Third Hospital Beijing 100191China Instiute of Medical Innovation Peking University Third HospitalBejing 100191China

Dear Editor,Since December 2019,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has been rapidly spreading *** and chloroquine are candidates for the treatment of coronavirus disease 2019(COVID-19)owing to ... 详细信息

关键词： acute respiratory patients