混合菌群FF降解染料效果及生物毒性变化

利用混合菌群FF降解偶氮染料活性黑5和蒽醌染料活性蓝19,通过检测一些常规指标,如脱色率、DOC(溶解性有机碳)去除率、UV254、比紫外吸收值SUVA(UV254/DOC)等来表征降解效果,进一步通过固相萃取方法进行前处理,采用SOS/umu(又称umu试验)和双杂交酵母法分别检测染料降解过程中遗传毒性和抗雌激素活性。结果表明,采用混合菌群FF,活性黑5和活性蓝19(150 mg/L)在35℃和p H=8.0条件下静置培养48 h后脱色率分别为82.5%和89.2%;DOC去除率低,分别为19.5%和13.0%;降解后UV254和SUVA均增加。遗传毒性检测表明,活性黑5本身无遗传毒性,降解过程中也无遗传毒性;活性蓝19本身无遗传毒性,降解24 h、48 h后在高浓缩倍数下出现遗传毒性。随着降解的进行,活性黑5和活性蓝19的抗雌激素活性均显著增加。     

A systems-theoretic approach for two-stage emergency risk analysis

Coronavirus disease (COVID-19) is an infectious disease that has dramatically spread worldwide. Regarding the safety issues of industries, there is a requirement of dealing with the emergency risk in the period of urgent situations. In this work, we proposed a systems-theoretic approach of the two-stage emergency risk analysis (ERA) based on the systems theory, that is the System-Theoretic Accident Model and Processes (STAMP). The two-stage ERA includes the normal to emergency risk analysis (N2E-RA) and emergency to normal risk analysis (E2N-RA). Besides N2E-RA, we advocate that E2N-RA is also an important and indispensable part of ERA. We elaborated the characteristics of N2E-RA and E2N-RA, separately. Eventually, based on our analysis, we provided recommendations for decision makers in preventing and controlling industrial accidents in the period of COVID-19.     

Coltan from Central Africa,international trade and implications for any certification

The exploitation of coltan in Central Africa can be considered a case of conflict minerals due to its nature. Many international organizations and bodies, national governments and private sector organizations seek to address this conflict, in particular via transparency, certification and accountability along the material supply chain. This paper analyses the international trade dimension of coltan and gives evidence on the dimension of illicit trade of coltan. The authors start from the hypothesis that illicit trade of coltan sooner or later will enter the market and will be reflected in the statistics. The paper is structured in the following manner: first, a short section gives a profile of coltan production and markets; second, an overview of the mining situation in the Democratic Republic of Congo (DRC) and related actors. The third section addresses mechanisms, actors and measurement issues involved in the international trade of coltan. The final part draws lessons for certification and conflict analysis and offers some guidance for future research.     

疫情背景下的福建省高速公路机动车污染物排放清单

机动车排放污染物已经成为大气污染的重要来源.基于福建省高速公路交通流量数据,采用自下而上的计算方法建立了2020年1—7月福建省高速公路机动车高分辨率污染物排放清单.结果表明,受疫情影响,福建省高速公路月均车流量和污染物排放量呈先下降后上升的变化趋势,4月污染物排放量达到最低,5月污染物排放量又迅速恢复到疫情前的排放水平,其中,疫情中期污染物CO、HC、NO_x、PM_2.5和PM₁₀排放较疫情后期分别减少了90.68%、89.06%、92.58%、89.58%和89.63%.在整个研究期内,不同城市高速公路机动车污染物排放的分担率有所不同,泉州、福州和漳州的高速公路机动车排放分担率较高;从车型来看,小型客车和轻型货车是CO和HC的主要贡献车型,NO_x和PM主要来自重型货车和轻型货车;从燃料类型来看,汽油车是CO和HC的主要贡献源,柴油车则对NO_x和PM贡献突出;从排放标准来看,国三和国四车对各项污染物的贡献率最大.各项污染物空间分布一致,排放高值区位于东部沿海地区路段,西部内陆的...     

Heavy haze pollution during the COVID-19 lockdown in the Beijing-Tianjin-Hebei region, China

To investigate the characteristics of particulate matter with an aerodynamic diameter less than 2.5 μm (PM_2.5) and its chemical compositions in the Beijing-Tianjin-Hebei (BTH) region of China during the novel coronavirus disease (COVID-19) lockdown, the ground-based data of PM_2.5, trace gases, water-soluble inorganic ions, and organic and elemental carbon were analyzed in three typical cities (Beijing, Tianjin, and Baoding) in the BTH region of China from 5-15 February 2020. The PM_2.5 source apportionment was established by combining the weather research and forecasting model and comprehensive air quality model with extensions (WRF-CAMx). The results showed that the maximum daily PM_2.5 concentration reached the heavy pollution level (>150 μg/m³) in the above three cities. The sum concentration of SO₄²⁻, NO₃⁻ and NH₄⁺ played a dominant position in PM_2.5 chemical compositions of Beijing, Tianjin, and Baoding; secondary transformation of gaseous pollutants contributed significantly to PM_2.5 generation, and the secondary transformation was enhanced as the increased PM_2.5 concentrations. The results of WRF-CAMx showed obviously inter-transport of PM_2.5 in the BTH region; the contribution of transportation source decreased significantly than previous reports in Beijing, Tianjin, and Baoding during the COVID-19 lockdown; but the contribution of industrial and residential emission sources increased significantly with the increase of PM_2.5 concentration, and industry emission sources contributed the most to PM_2.5 concentrations. Therefore, control policies should be devoted to reducing industrial emissions and regional joint control strategies to mitigate haze pollution.     

Sonographic findings in Beckwith–Wiedemann syndrome related to H19 hypermethylation

Beckwith–Wiedemann syndrome (BWS) is an overgrowth syndrome associated with congenital malformations and tumour predisposition. BWS results from variable mutations or epigenetic modifications of imprinted genes in the 11p15 chromosomal region. We present a fetus with mild general overgrowth and bilateral enlarged echogenic kidneys with loss of the corticomedullary differentiation in which prenatal diagnosis of BWS was suspected. The rest of the fetal anatomy and the amniotic fluid volume appeared normal. After termination of the pregnancy, molecular analysis confirmed the diagnosis of BWS by showing an isolated hypermethylation of the H19 gene. Copyright © 2004 John Wiley & Sons, Ltd.     

河南省春节和疫情影响情景下PM2.5组分特征

2020年1月我国爆发了新型冠状病毒疫情,期间我国各地区大气污染源排放特征发生了显著改变.为研究该情景下PM_2.5组分特征,本研究于2020年1月1日~2月13日利用在线观测仪器对郑州、安阳和新乡市进行连续观测.根据春节假期和疫情爆发,将研究时期分为春节前（1月1~23日）、春节疫情期（1月24~31日）和节后疫情期（2月1~13日）.受疫情和有利的气象条件影响,节后疫情期间郑州、安阳和新乡市除O₃外其它污染物浓度较春节前均明显下降,其中NO₂和PM_2.5的降幅分别为65%、52%、72%和51%、55%、54%,但是污染物浓度仍较高,表明未来河南省冬季大气污染的较大幅度改善面临巨大挑战.从颗粒物组分来看,二次无机盐和有机物是观测期间PM_2.5的主要组分.春节疫情期3个城市受烟花爆竹的影响较小,并且硝酸根和扬尘的贡献相比春节前轻微下降.节后疫情期间郑州、安阳和新乡市PM_2.5中硝酸根浓度和占比显著下降,占比降幅为10.6%、4.1%和4%;硫酸根和有机物的占比上升,其中二次有机碳的贡献增大.以郑州市为例分析硝酸盐生成,相比春节前,节后疫情期间不同污染时段硝酸根的占比均下降,但硝酸根仍是污染时段PM_2.5中占比最高的组分.日变化特征表明节后疫情期间大气中O₃浓度和湿度的增高可能促进了NO₂的转化,因此下一步应采取PM_2.5和O₃的协同管控,重视NO₂和VOCs的协同减排.     

影响病毒在物体表面和空气中生存的因素分析

新型冠状病毒肺炎（COVID-19）疫情严重危害人类生命安全和影响国家经济发展.截至目前,关于环境条件（湿度与温度）、空气污染及人为活动对2019-nCoV传播的文献鲜见报道.由于新型冠状病毒（2019-nCoV）采样困难,难以开展直接试验研究,因此通过对国内外其他类似病毒文献调研,探究影响病毒传播和生存的影响因素,以期为疫情防控和控制2019-nCoV传播提供指导.结果表明:①冠状病毒在低温低湿的环境中能够保持较长的存活时间与传播力,尤其在干燥物体表面停留时间更长,如冠状病毒能在温度为22~25℃、相对湿度（RH）为40%~45%的光滑物体表面存活5 d以上;②同时,冠状病毒气溶胶在低温低湿的条件下也具有高存活率,提示在密闭环境中2019-nCoV气溶胶可能在温度为20~25℃、相对湿度为30%~50%的条件下具有较高的存活率;③颗粒物浓度越高,2019-nCoV传播的风险可能随之增加;④感染者的行为活动也对2019-nCoV的传播起着不可忽视的作用,应避免在人群中打喷嚏、咳嗽,并且用手、手肘或其他物品加以防护,降低病毒传播的可能性.综上,提出几点疫情防控的相关建议,如改善室内微环境和开展2019-nCoV的检测、灭活、影响因素、传播规律等相关研究工作.      

Variability of PM2.5 and O3 concentrations and their driving forces over Chinese megacities during 2018-2020

Recently,air pollution especially?ne particulate matters (PM_2.5) and ozone (O₃) has become a severe issue in China.In this study,we?rst characterized the temporal trends of PM_2.5and O₃for Beijing,Guangzhou,Shanghai,and Wuhan respectively during 2018-2020.The annual mean PM_2.5has decreased by 7.82%-33.92%,while O₃concentration showed insigni?cant variations by-6.77%-4.65%during 2018-2020.The generalized additive models (GAMs) were ...     

壬基酚对斑马鱼精巢组织及性激素合成酶基因表达的影响

壬基酚（NP）是广泛存在于水体中的环境内分泌干扰物,会影响鱼类的生殖和发育.为了解NP影响鱼类精巢发育的分子机制,将成年雄性斑马鱼（Danio rerio）暴露于不同浓度（0、125、250、500μg·L-1）NP下21d,用常规组织学方法研究试验鱼精巢组织结构的变化,并用荧光定量PCR（QRT-PCR）方法检测试验...