Does anthracene affect microbial activities and organic matter decomposition? A comparative study in Pinus halepensis litters from Mediterranean coastal and inland areas

The widespread concern about pollution caused by Polycyclic Aromatic Hydrocarbons (PAHs) raises the question of how they affect soil microbial communities which are potentially involved in the transformation of these pollutants. Using microcosms, we describe the effect of anthracene, a model PAH, on microbial communities inhabiting a Pinus halepensis litter from both coastal (COS) and inland (INL) Mediterranean sites. The microcosms were incubated over 3 months (25 °C, 60% WHC) and the effects of anthracene on microbial activities of both litters were monitored. Different enzyme activities (laccase, cellulase, β-glucosidase and acid phosphatase) and microbial respiration were measured and variations in litter chemical composition over incubation were determined using ¹³C Nuclear Magnetic Resonance (NMR) from both sites. Our results show that lignocellulolytic enzymes increased markedly after a 3-month incubation in COS microcosms, especially in the presence of anthracene, whereas INL microcosms were not similarly affected. These results show that anthracene not only has no toxic effect on the microbial activities tested but actually enhances the lignocellulolytic activities of the fungal communities from coastal litters, demonstrating the detoxification potential and resistance of stressed Mediterranean coastal ecosystems.     

An uncertainty based multi-criteria ranking system for open pit mining cut-off grade strategy selection

Cut-off grade strategy (COGS) is a concept that directly influences the financial, technical, economical, and environmental issues in relation to the exploitation of a mineral resource. Despite the simple definition of cut-off grade, the COGS problem is one of the complex and complicated problems in the mine planning process. From the optimization point of view, the COGS with an objective of maximizing the present value of future cash flows is a non-linear and a non-convex problem that even in its deterministic form can be solved using approximate optimization methods. This optimization problem will also be more complex and complicated under uncertainty conditions. This paper proposes an uncertainty based multi-criteria ranking system to investigate the problem of COGS selection considering metal price and geological uncertainties. The proposed system aims at selection of the best COGS among technically feasible alternative COGSs under uncertainty circumstances. Our developed system is based on integrating metal price and geological uncertainties as well as operating flexibility to close the mine early. We incorporate this operating flexibility into the proposed system using a Monte Carlo based real options (RO) valuation model. For this purpose, in addition to the expected value, other risk criteria are considered to rank the alternatives. These risk criteria include abilities of strategies in producing extra profits, minimizing losses, and achieving the predefined goals of the production. In this study, the technically possible COGSs are generated using the Lane comprehensive algorithm. To demonstrate the effectiveness of the proposed system, we utilize data of an Iranian gold mine. Results show that the proposed system outperforms conventional methods in the sense that it shows significantly lower average mis-ranking than the other methods and also selects a strategy with a higher value. The sensitivity analysis of the proposed system relative to the gold price shows that the system is highly dependent on the parameters of the stochastic process used to model the evolution of the metal price. Therefore, special consideration should be given in estimating stochastic process parameters.     

Long-term impacts of exposure to high temperatures on human capital and economic productivity

Weather anomalies have a range of adverse contemporaneous impacts on health and socio-economic outcomes. This paper tests if temperature anomalies around the time of birth can have long-term impacts on individuals' economic productivity. Using unique data sets on historical weather and earnings, place and date of birth of all 1.5 million formal employees in Ecuador, we find that individuals who have experienced in-utero temperatures that are 1 °C above average are less educated and earn about 0.7% less as adults. Results are robust to alternative specifications and falsification tests and suggest that warming may have already caused adverse long-term economic impacts.     

Al(Ⅲ) speciation distribution and transformation in high concentration PACl solutions

Effects of Al（Ⅲ） concentration and pH on the speciation of Al（Ⅲ） in polyaluminum chloride （PACl） solutions especially on the Al13 fraction were investigated. A series of PACl samples were prepared over the range of Al（Ⅲ） concentration from 0.01 to 2.0 mol/L with the B （OH/Al ratio） value from 1.0 to 2.5 by forced hydrolysis of AICl3. The samples were characterized by ferron assay, pH and 27^Al NMR. It was shown that the Al（Ⅲ） concentration had a dramatic effect on the hydrolysis processes and the species distribution of PACl was in relate to the decrease of pH. The fraction of Al species, Alb （or Al13） decreased and Al0 increased with increase of total Al（Ⅲ） concentration. Under the condition of Al（Ⅲ） 2.0 reel/L, B = 2.5, the pH value was 2.73 and no Al13 could be detected. During diluting and aging, the species distribution evoIved. The Al13 could then be detected again and the amounts increased with time. If the diluted samples were concentrated by freeze dry at -35℃ or heating at 80℃, the pH value and Al13 content would decrease with the increased concentration. It demonstrated that the key factor for formation of Al13 in concentrated PACl was pH value.     

Gas stable isotopic ratio mass spectrometry for measuring δ^13C and δ^18O in background atmospheric CO2

将商用MAT253稳定同位素比质谱仪、Airtrap高效预浓缩气体捕集阱与自加工16口自动进样器集成,建立了高精度气体稳定同位素比质谱分析系统,用于程序化自动分析本底大气CO2的δ^13C和δ^18O．气样分析时用工作标气定量并穿插目标气测定,还定期用实验室上一级标气对工作标气和参比气进行标校,以保证分析结果的可靠和可比．结果表明,利用不同稳定同位素比范围的标气重复进样测试,发现该系统对δ^13C和δ^18O的分析精度分别优于0．03‰和0．06‰,能基本满足本底大气CO2的碳氧稳定同位素比分析需求和WMO／GAW质量目标．     

喀斯特小流域内不同背景区植物解剖结构与植物叶片δ13C的关系研究

本文应用光学显微镜和电子扫描显微镜的方法测量了生长在贵州省清镇市王家寨小流域内不同背景区(喀斯特与非喀斯特)11种植物的叶片解剖结构,比较了不同背景区整体植物以及各样地之间相同植物的叶片解剖结构与其δ13C值的相关关系。研究结果表明,研究区内所有植物从非退化到退化过程中的叶片解剖结构与δ13C值呈现显著的正相关关系,喀斯特背景区的竹叶椒和小叶鼠李,非喀斯特背景区的粉枝莓、油茶和构树的叶片解剖结构与δ13C值也呈现显著的正相关关系,喀斯特背景区与非喀斯特背景区植物具有比较一致的变化趋势,而生长在两背景区的同种植物叶片解剖结构和δ13C值均无显著性差异。这说明了在本研究小流域内,由于光、热、水、气等外部影响因素的一致性,不同背景区从非退化样地到退化样地的发展过程中,植物叶片的解剖形态特征为了适应环境的改变而产生了相同的响应趋势,这些响应变化均与植物叶片的δ13C值具有正相关关系,尤其是石漠化样地上的植物叶片解剖形态特征以及其δ13C值对生境条件的响应是最迅速和最敏感的。     

Prenatal diagnosis of complete trisomy 19q

This communication presents the first case of complete trisomy 19q, prenatally detected by ultrasound investigation. Real-time high-resolution ultrasound examination was performed at 19 weeks of gestation. After termination of the pregnancy, autopsy investigation was done. GTG-banding, fluorescence in situ hybridization m-(FISH) analysis, and FISH analysis with a 19q subtelomeric specific probe were used for identification of the fetal karyotype. Sonographic examination revealed an enlarged cisterna magna, cerebellar hypoplasia and aplasia of the inferior part of the vermis, combined and bilateral kidney malformations, significant nuchal fold, absence of fetal nasal bones, and intracardial calcifications. Autopsy confirmed ultrasound findings, but also revealed situs viscerum inversus of the lungs. Fetal karyotype was defined as: 46,XY,der(21)t(19;21)(q11;p13)mat. Our ultrasound and autopsy findings will certainly contribute to better knowledge of phenotype characterization of this rare chromosomal disorder. Copyright © 2007 John Wiley & Sons, Ltd.     

Prenatally detected trisomy 4 and 6 mosaicism—cytogenetic results and clinical phenotype

We report on a live-born male with 46,XY/47,XY+4/47,XY,+6 mosaicism. Trisomy 4 mosaicism was detected by karyotyping chorionic villus samples (CVS) and was confirmed by the analysis of 16 metaphases obtained from cultured amniotic fluid cells. Eight metaphases were normal (46,XY), two had trisomy 4 (47,XY,+4), and two had trisomy 6 (47,XY,+6). Two postnatal chromosomal analyses of blood lymphocytes at birth and at the age of one week were normal. Chromosomal analysis of cultured skin fibroblasts from the right inguinal region at the age of 12 months revealed trisomy 4 (47,XY,+4) in 49 metaphases, trisomy 6 (47,XY,+6) in 2 metaphases, and a normal karyotype (46,XY) in 49 cells of the 100 analyzed metaphases, respectively. The main clinical findings consist of prenatal growth retardation, hypoplasia of the right side of the face, a dysplastic and posteriorly rotated right ear, a high vaulted palate, retrognathia, aplasia of the right thumb, hypoplasia of the fingernails, a deep sacral dimple, and patchy skin hypopigmentation of the right leg. When last seen at the age of 14 months, his development was nearly normal. Five patients with trisomy 4 mosaicism have been reported previously, but none with an additional trisomy 6 mosaicism. Copyright © 2003 John Wiley & Sons, Ltd.     

~（13）C同位素稀释法测定国产多氯联苯的2，3，7，8－TCDD毒性当量

应用质量控制方法测定了２种国产商品多氯联苯（ＰＣＢｓ）中１７个２，３，７，８位有氯取代的二　同族体，获得准确的定量结果，加入￣（１３）Ｃ标记物的ＰＣＢｓ样品用多级酸碱硅胶柱和氧化铝柱提取分离，用毛细管色谱／高分辨质谱定量，２种样品中都含有较多的２，３，７，８－ＴＣＤＦ和２，３，７，８－Ｐ＿５ＣＤＦ。１￣＃ＰＣＢ的２，３，７，８－ＴＣＤＤ毒性当量值为２１７ｎｇ／ｇ，２￣＃ＰＣＢ为４１７ｎｇ／ｇ，毒性主要来自ＰＣＤＦｓ，并与国外同类商品ＰＣＢｓ作了比较。     

西藏自治区“十二五”和“十三五”环境空气质量变化特征

"十二五"以来中国先后颁布了一系列大气污染防治政策并实施相应的大气污染治理措施以提高环境空气质量。为研究西藏自治区"十二五"(2011-2015年)和"十三五"(2016 -2020年)时期环境空气质量变化状况,评估大气污染防治措施实施效果,笔者对2011-2020年西藏自治区7个城市(地区)主要大气污染物浓度和优良天数比例变化进行分析。结果表明:随着一系列大气污染防治措施的实施,西藏自治区环境空气质量显著提升,与"十二五"时期相比,"十三五"时期西藏自治区年平均优良天数比例由97.5%±2.0%提升至99.3%±0.4%,SO₂、 NO₂、 PM₁₀、 PM_2.5浓度年均值和CO 浓度第95百分位数均呈下降趋势,其中CO、PM₁₀和PM_2.5浓度下降幅度较大,O₃日最大8h滑动平均值第90百分位数略有上升。西藏自治区环境空气质量与人口、经济发展程度呈负相关关系。受污染源排放、气象条件和区域传输等因素影响,西藏自治区O₃浓度春、夏季较高,而其余污染物浓度冬季较高。