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Perfluorooctanoic acid(PFOA) and perfluorooctanesulfonic acid(PFOS) concentrations in the South Korean agricultural environment: A national survey

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Journal of Integrative Agriculture 2017年第8期16卷 1841-1851页

作者： Geun-Hyoung Choi Deuk-Young Lee dong-Kyu jeong Saranya Kuppusamy Yong Bok Lee Byung-jun Park Jin-Hyo Kim Chemical Safety Division National Institute of Agricultural ScienceRural Development Administration Division of Applied Life Science(BK21 Plus) Institute of Agriculture and Life Science(IALS)Gyeongsang National University

Research on the occurrence of perfluorochemicals （PFCs） such as perfluorooctanesulfonic acid （PFOS） and perfluorooctanoic acid （PFOA） in the agricultural environment is lacking, in spite of their potential risk via food chain transfer from aquatic and soil-plant systems to animals and/or humans. In the present study, for the first time, soil and water samples collected from 243 different agricultural sites adjacent to waste water treatment plants （WWTPs） belonging to 81 cities and 5 provinces with different levels of industrialization in South Korea were monitored for concentrations of PFOS and PFOA by use of solid phase extraction and liquid chromatography-tandem mass spectroscopy （LC-MS/MS）. Significant mean concentrations of PFOA （0.001-0.007 tJg L-1 water and 〈0.05-1.573 tJg kg-1 soil） and PFOS （0.001-0.22 tJg L-1 water and 〈0.05-0.741 pg kg-1 soil） were found in all samples. Concentrations of PFCs in soils were high, highlighting that soil is an important sink for PFCs in the agricultural environment. Samples from near WWTPs in Gyeongsang Province contained the highest concentrations of PFOS and PFOA, reflecting the concentration of heavy industry in the province. The concentrations of PFCs in agricultural water （most samples 〈0.05 pg L-~） and soils （most samples 〈1 IJg kg-~） from South Korea were less than acceptable guideline values, indicating that South Korea is not a hotspot of PFOS and PFOA contamination and that there is negligible risk to human and ecological health from these chemicals. However, further studies investigating the seasonal variation in PFOA, PFOS and other perfluorochemical concentrations in the agricultural environment are needed.

关键词： PFOS PFOA agricultural environment residual concentration South Korea

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Local Well-posedness for Linearized Degenerate MHD Boundary Layer Equations in Analytic Setting

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Acta Mathematica Sinica,English Series 2019年第8期35卷 1402-1418页

作者： Ya jun LI Wen dong WANG School of Mathematical Sciences Dalian University of Technology

In this note we derive MHD boundary layer equations according to viscosity and resistivity coefficients. Especially, when these viscosity and resistivity coefficients are of different orders, it leads to degenerate MH... 详细信息

关键词： MHD equations degenerate boundary layer equations local well-posedness analytic spaces

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Upgrading and upstaging of low-risk prostate cancer among Korean patients： a multicenter study

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Asian Journal of Andrology 2015年第5期17卷 811-814,I0009页

作者： Insang Hwang donghoon Lim Young Beom jeong Seung Chol Park jun Hwa Noh dong Deuk Kwon Taek Won Kang Department of Urology Chonnam National University Medical School Gwangju Korea Department of Urology Chosun University Medical School Gwangju Korea Department of Urology Chonbuk National University Medical School Jeonju Korea Department of Urology Wonkwang University School of Medicine Iksan Korea Department of Urology Kwangju Christian Hospital Gwangju Korea

Only 54% of prostate cancer cases in Korea are localized compared with 82% of cases in the US. Furthermore, half of Korean patients are upgraded after radical prostatectomy （41.6%-50.6%）. We investigated the risk factors for upgrading and/or upstaging of low-risk prostate cancer after radical prostatectomy. We retrospectively reviewed the medical records of 1159 patients who underwent radical prostatectomy at five hospitals in Honam Province. Preoperative data on standard clinicopathological parameters were collected. The radical prostatectomy specimens were graded and staged and we defined a ＂worsening prognosis＂ as a Gleason score ≥ 7 or upstaging to ≥ pT3. Multivariate logistic regression models were used to assess factors associated with postoperative pathological upstaging. Among the 1159 patients, 324 were classified into the clinically low-risk group, and 154 （47.5%） patients were either upgraded or upstaged. The multivariable analysis revealed that the preoperative serum prostate-specific antigen level （odds ratio [OR], 1.131; 95% confidence interval [CI], 1.007-1.271; P = 0.037）, percent positive biopsy core （OR： 1.018; 95% CI： 1.002-1.035; P = 0.032）, and small prostate volume （≤30 ml）（OR： 2.280; 95% CI： 1.351-3.848; P = 0.002） were predictive of a worsening prognosis. Overall, 47.5% of patients with low-risk disease were upstaged postoperatively. The current risk stratification criteria may be too relaxed for our study cohort.

关键词： prostate cancer prostatectomy risk factors

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Just for Chinese people s stood up——*** Gu,father of“sugar pills”

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Protein & Cell 2020年第4期11卷 231-234页

作者： jun Wu Dexiang dong Ying Li Institute of Medical Biology Chinese Academy of Medical SciencesKunming 650118China

Professor Fangzhou Gu(顾方舟)was bom in Shanghai in june *** is a medical scientist,expert virologist,member of the Third World Academy of Sciences,the former president and first-level professor of Peking Union Medical College of Chinese Academy of Medical *** September 17,2019,Professor Fangzhou Gu was awarded national medals and honorary titles together with 42 people and he was conferred the “People's Scientist” national honorary title(Fig.1).

关键词： Just sugar College

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A Construction of Maximal Linearly Independent Array

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Acta Mathematica Sinica,English Series 2010年第7期26卷 1331-1344页

作者： jun Wu dong Xue Li WANG College of Mathematics and Econometrics Hu'nan University Changsha 410082 P. R. China College of Mathematics and Information Science Guangzhou University Guangzhou 510006 P. R. China School of Mathematical Sciences South China Normal University Guangzhou 510631 P. R. China

Let M be a subset of r-dimensional vector space Vτ （F2） over a finite field F2, consisting of n nonzero vectors, such that every t vectors of M are linearly independent over F2. Then M is called （n, t）-linearly independent array of length n over Vτ（F2）. The （n, t）-linearly independent array M that has the maximal number of elements is called the maximal （r, t）-linearly independent array, and the maximal number is denoted by M（r, t）. It is an interesting combinatorial structure, which has many applications in cryptography and coding theory. It can be used to construct orthogonal arrays, strong partial balanced designs. It can also be used to design good linear codes, In this paper, we construct a class of maximal （r, t）-linearly independent arrays of length r ＋ 2, and provide some enumerator theorems.

关键词： maximal linearly independent array orthogonal array hamming weight

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Theoretical Investigation on Hyperfine Structures of Perfluoropolyether Radicals

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Chemical Research in Chinese Universities 2011年第1期27卷 117-122页

作者： dong Su-li LIU Ya-jun Key Laboratory of Theoretical and Computational Photochemistry Ministry of Education College of Chemistry Beijing Normal University Beijing 100875 P. R. China

The geometries of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2 radicals were investigated by density functional theory（DFT） method. The calculated results indicate that all the three radicals have pyramidal shapes at their centers, and the aC is one top of the pyramids. Based on the DFT optimized geometries, the hyperfine coupling constants（hfec＇s） of the 19F atoms of the three radicals were calculated by B3LYP, MP2（full） and QCISD（full） methods. The calculated values agree with the experimental values, especially for the a values of Fa, the a values are 125.6× 10 -4, 104.2× 10 - 4, and 83.2×10 -4 T of CF3OCF2, CF3OCFCF3 and CF3OCF2CF2, respectively. These results better explain the experimental observation.

关键词： Perfluoropolyether radical Hyperfine coupling constant Density functional theory

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Asymptotic behavior for sums of non-identically distributed random variables

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Applied Mathematics(A Journal of Chinese Universities) 2019年第1期34卷 45-54页

作者： YU Chang-jun CHENG dong-ya School of Sciences Nantong University School of Mathematical Sciences Soochow University The Statistics and Operations Research Department the University of North Carolina at Chapel Hill

For any given positive integer m, let X_i, 1 ≤ i ≤ m be m independent random variables with distributions F_i, 1 ≤ i ≤ m. When all the summands are nonnegative and at least one of them is heavy-tailed, we prove that the lower limit of the ratio ■equals 1 as x →∞. When the summands are real-valued, we also obtain some asymptotic results for the tail probability of the sums. Besides, a local version as well as a density version of the above results is also presented.

关键词： lower limits upper limits heavy-tailed distributions local distributions densities

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AN ANALYTICAL SOLUTION FOR THREE-DIMENSIONAL DIFFRACTION OF PLANE P-WAVES BY A HEMISPHERICAL ALLUVIAL VALLEY WITH SATURATED SOIL DEPOSITS

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Acta Mechanica Solida Sinica 2006年第2期19卷 141-151页

作者： Zhao Chenggang dong jun Gao Fuping School of Civil Engineering and Architecture Beijing Jiaotong University Beijing 100044 China Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

An analytical solution for the three-dimensional scattering and diffraction of plane P-waves by a hemispherical alluvial valley with saturated soil deposits is developed by employing Fourier-Bessel series expansion technique. Unlike previous studies, in which the saturated soil deposits were simulated with the single-phase elastic theory, in this paper, they are simulated with Biot＇s dynamic theory for saturated porous media, and the half space is assumed as a single-phase elastic medium. The effects of the dimensionless frequency, the incidence angle of P-wave and the porosity of soil deposits on the surface displacement magnifications of the hemispherical alluvial valley are investigated. Numerical results show that the existence of a saturated hemispherical alluvial valley has much influence on the surface displacement magnifications. It is more reasonable to simulate soil deposits with Biot＇s dynamic theory when evaluating the displacement responses of a hemispherical alluvial valley with an incidence of P-waves.

关键词： Biot's dynamic theory three-dimensional scattering hemispherical alluvial valley,analytical solution

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Invariant Hyperbolic Tori for Gevrey-smooth Hamiltonian Systems Under Rfissmann's Non-degeneracy Condition

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Acta Mathematica Sinica,English Series 2008年第10期24卷 1625-1636页

作者： dong Feng ZHANG jun Xiang XU Department of Mathematics Southeast University Nanjing 210096 P. R. China

In this paper, we prove the persistence of hyperbolic lower dimensional invariant tori for Gevrey-smooth perturbations of partially integrable Hamiltonian systems under Riissmann＇s nondegeneracy condition by an improved KAM iteration, and the persisting invariant tori are Gevrey smooth, with the same Gevrey index as the Hamiltonian.

关键词： hyperbolic invariant tori KAM iteration Gevrey-smooth non-degeneracy condition

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Neighbor Sum Distinguishing Total Colorings of Graphs with Bounded Maximum Average Degree

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Acta Mathematica Sinica,English Series 2014年第4期30卷 703-709页

作者： Ai jun dong Guang Hui WANG School of Science Shandong Jiao Tong University School of Mathematics Shandong University

A proper [h]-total coloring c of a graph G is a proper total coloring c of G using colors of the set [h] ={1, 2,..., h}. Let w（u） denote the sum of the color on a vertex u and colors on all the edges incident to u. For each edge uv ∈ E（G）, if w（u） ≠ w（v）, then we say the coloring c distinguishes adjacent vertices by sum and call it a neighbor sum distinguishing [h]-total coloring of G. By tndi∑ （G）, we denote the smallest value h in such a coloring of G. In this paper, we obtain that G is a graph with at least two vertices, if mad（G）〈 3, then tndi∑ （G） ≤k ＋ 2 where k = max{△（G）, 5}. It partially confirms the conjecture proposed by Pilgniak and Wolniak.

关键词： Total coloring neighbor sum distinguishing total colorings average degree

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