Occurrence and spatial distribution of antibiotic resistance genes in the Bohai Sea and Yellow Sea areas, China

Rapid development of Bohai and Yellow Sea Economic Rim has led to the concern of emerging contamination of marine environments. This study investigated the spatial distribution of antibiotic resistance genes (ARGs) in Bohai and Yellow Sea areas. A large scale sampling from Bohai Sea, Yellow Sea and the major cities along the coastline from the mouth of Yalu River to the Yangtze River was performed. The spatial distribution of target ARGs based on the absolute abundances was in the trend of river water coastal water > the Bohai Sea > the Yellow Sea, inshore > offshore and inner bay > bay mouth. The total absolute abundances of selected ARGs in the coastal waters (1.23 x 10(4)-3.94 x 10(5) copies/mL) were about 1-4 orders of magnitude higher than those in the sea (21.1-8.00 x 10(3) copies/mL). The abundances of ARGs fluctuated greatly in the Yellow Sea and the coastal areas. Sulfonamide resistance genes hold the highest abundances in the Bohai and Yellow Sea (up to 2.13 x 10(3) copies/mL of still and 6.23 x 10(3) copies/mL of sul2), followed by tetracycline and quinolone resistance genes, while qnrA hold the highest abundances in coastal areas (up to 3.66 x 10(5) copies/mL). The distribution coefficients of target genes between sediments and corresponding water samples were more than 1.0 in the majority of different aquatic systems. According to the principle component analysis and redundancy analysis, water samples collected from the sea clustered together while those from the coastal zone and rivers were separated. Ammonium and nitrate played important roles in the distribution and variation of ARGs. Co-occurrence network analysis revealed that the potential multi-antibiotics resistant bacteria were detected with higher abundances in the Yellow Sea than in the Bohai Sea. These observations provided a comprehensive new insight into the pollution status of ARGs in the Bohai and Yellow Sea areas. (C) 2019 Elsevier Ltd. All rights reserved

Phycoremediation of coastal waters contaminated with bisphenol A by green tidal algae Ulva prolifera

The phycoremediation of coastal water contaminated with bisphenol A (BPA) by Ulva prolifera (U. prolifera) during green tide blooming was investigated. The results demonstrated that BPA could be removed rapidly in the presence of U. prolifera. >94.3% of BPA was removed by live U. prolifera while 94%) was achieved at the environmental relevant concentrations of BPA. The field investigation indicated that the BPA concentration in the coastal water in the green tide blooming area was much lower than that in the adjacent coastal water without green tide. The contribution of the green-tidal algae in the removal of BPA in the coastal waters was remarkable due to the high BPA removal efficiency, and high biomass & huge covered area of the U. prolifera during the outbreak of green tide. These findings demonstrate a new important phycoremediation process for coastal water containing typical endocrine-disrupting chemicals (EDCs) during the green tide blooming. (C) 2019 Elsevier B.V. All rights reserved

Proliferation of antibiotic resistance genes in coastal recirculating mariculture system

The abuse of antibiotics has caused the propagation of antibiotic resistance genes (ARGs) in aquaculture systems. Although the recirculating systems have been considered as a promising approach for preventing the coastal water pollution of antibiotics and ARG, rare information is available on the distribution and proliferation of ARGs in the recirculating mariculture system. This study firstly investigated the proliferation of ARGs in coastal recirculating mariculture systems. Ten subtypes of ARGs including tet (tetB, tetG, tetX), sul (sul1, sul2), qnr (qnrA, qnrB, qnrS), and erm (ermF, ermT) were detected. The absolute abundances of the ARGs detected in the mariculture farm were more than 1 x 10(4) copies/mL. The sulfonamide resistance genes (sul1 and sul2) were the most abundant ARGs with the abundance of 3.5 x 10(7) -6.5 x 10(10) copies/mL. No obvious correlation existed between the antibiotics and ARGs. Some bacteria were positively correlated with two or more ARGs to indicate the occurrence of multidrug resistance. The fluidized-bed biofilter for wastewater treatment in the recirculating system was the main breeding ground for ARGs while the UV sterilization process could reduce the ARGs. The highest flux of ARGs (6.5 x 10(21) copies/d) indicated that the discharge of feces and residual baits was the main gateway for ARGs in the recirculating mariculture system to enter the environments. (C) 2019 Elsevier Ltd. All rights reserved

Adsorptive removal of polycyclic aromatic hydrocarbons by detritus of green tide algae deposited in coastal sediment

Rare information is available on the adsorptive removal of polycyclic aromatic hydrocarbons (PAHs) in the presence of algal detritus deposited in the coastal sediment during the outbreak of the green tide. The adsorptive removal of typical PAHs by Ulva prolifera (U. prolifera) detritus was firstly investigated since the algal detritus was of great importance for the biogeochemical cycle of coastal contaminants. The results showed that equilibrium adsorptive capacities of naphthalene, phenanthrene and benzo[a] pyrene on the U. prolifera detritus were 1.27, 1.97, and 2.49 mg kg−1, respectively, at the initial concentration of 10 μg L−1. The in situ monitoring using laser confocal scanning microscopy confirmed the adsorptive removal of PAHs by U. prolifera detritus. The adsorption of these PAHs was highly pH-dependent. The increase in salinity led to the increase in naphthalene removal rate, while the salinity showed scarce influence on the removal of phenanthrene and benzo[a] pyrene. There was a good linear relationship (R2 ≥ 0.9892) between the removal efficiency of PAHs and the initial concentration of PAHs. Slow desorption kinetics and low desorption rate ( © 2019 Elsevier B.V

Influence of coastal groundwater salinization on the distribution and risks of heavy metals

Coastal groundwater quality significantly affects the regional sustainable development, due to the water resource shortage in coastal zone. Current studies on coastal groundwater have mainly focused on saline water intrusion and over-extraction. Information on the heavy metal pollution of coastal groundwater with salinization trend is limited. This study investigated heavy metals in groundwater from a typical coastal region with intensive anthropogenic activities and saline water intrusion. The southwestern coastal plains of the study area showed significant groundwater salinization trend. Heavy metals in the coastal groundwater mainly originated from anthropogenic activities and groundwater salinization according to principal component analysis. Relative high concentrations of As, Co, Cr, Cu, Fe, Mn, and Ni occurred in the southwestern coast of the study area with high TDS level, indicating that the concentrations of these heavy metals in shallow aquifer of the study area might be influenced by the groundwater salinization. Average concentrations of heavy metals in groundwater of the study area ranged from 0.03 (Cd) to 686.92 (Fe) mu g/L. Fe was the dominant heavy metal in groundwater with the maximal concentration of 2333.76 mu g/L and exceeding-standard rate reaching 98.23%. Approximately 13.27% of sampling sites showed moderate or higher heavy metal pollution of groundwater based on heavy metal pollution index. Heavy metals in groundwater exerted low ecological risks. Elements Fe, Ni, and As were the main contributors for ecological risks. Cancer risks of heavy metals for both adults and children were high at all sampling sites. Non-cancer risks for adults and children were unacceptable at 4.42% and 17.70% of sampling sites, respectively. The salinization of the coastal groundwater could also lead to the increase in the ecological and health risks of heavy metals in coastal groundwater. These findings provide initial and important information on heavy metals pollution in coastal aquifer with saline water intrusion. (C) 2018 Elsevier B.V. All rights reserved

不可压缩向列型液晶系统Cauchy问题整体强解的存在性和大时间性质

本文研究非齐次不可压缩向列型液晶系统在三维全空间上的Cauchy问题.对任意的β∈(1/2,1],当初值的范数■充分小时,本文证明整体强解的存在性及大时间衰减估计,其中初始密度可含真空或具有紧支集.国家自然科学基金(批准号:11601218,11771382和11671333)资助项

便携式拉曼光谱仪快速检测唾液中盐酸吡格列酮的含量

人体唾液与血液中的相应成分有着密切关系。利用唾液代替血液进行检测,可极大地缩短分析时间、减少检测限制、降低安全隐患等,因此在临床医学、毒品管控等方面均有重要意义。发展了便携式拉曼光谱仪利用表面增强拉曼光谱技术快速定量检测唾液中盐酸吡格列酮（口服降血糖药物）含量的方法。借助纳米金溶胶的表面增强拉曼散射效应,在激发光源波长为785 nm时,可以得到低浓度盐酸吡格列酮的高质量拉曼光谱图。同时,不同浓度盐酸吡格列酮表面增强拉曼光谱分析结果表明,该方法还可直接用于唾液中盐酸吡格列酮的定量检测。盐酸吡格列酮含量与其特征峰强度线性相关,相关系数为0. 992 3,且最低检测浓度达10μg·L-1。国家自然科学基金项目(21522508);;深圳市科技计划基础研究(自由探索)项目(JCYJ20170306140934218)资

一种混沌网络简单电路实现

本文利用简单的非线性电子元件设计成混沌电路，该电路具有设计简单，易于集成等特点。利用多控制参数使得该混沌电路具有丰富的混沌动力学行为，本文利用Lyapunov指数，从理论上分析控制参数对电路输出的影响。根据理论分析结果，调节电路的参数，可以成功地看到不动点、倍周期、混沌现象。这一简单电路可望在混沌神经网络，混沌通讯领域获得应用

厦门综改区社会管理创新的实践及其特色

创新社会管理是厦门全面实施综合配套改革试验的重要内容。本文探索厦门实施综合配套改革试验区在基层社区治理、基层公共服务、社会志愿参与、社会组织管理、涉台事务治理等五大领域的创新实践,总结其创新经验及特色。作者认为厦门综合配套改革试验区已经初步探索出一条以民生优先、协同治理、制度创新、技术支撑为特征的社会管理创新之路,逐步形成政府与其它社会主体协同创新的社会管理新模式。厦门大学985工程公共管理重点学科建设项目; 福建省2012年度社科规划重点项目“推进厦门综合配套改革试验区社会管理体制创新研究”(项目编号:2012A015

Thirty Years of Regulatory Detailed Planning: Gains and Losses, and Prospects

吕传廷(中国城市规划学会理事,中国城市规划学会控规学术委员会主任委员,广州市城市规划编制研究中心主任,教授级高级工程师,本论坛主持人):非常高兴诸位嘉宾、代表参加由广州城市规划编制研究中心、深圳规划国土发展研究中心、重庆规划研究中心三家单位联合举办的"控制