Biomarkers in croakers Micropogonias furnieri (Teleostei: Sciaenidae) from polluted and non-polluted areas from the Patos Lagoon estuary (Southern Brazil): evidences of genotoxic and immunological effects

Biomarkers of exposure and effect of pollutants were analyzed in croakers Micropogonias furnieri (Teleostei: Sciaenidae) captured in winter and summer in a polluted and in a non-polluted site at the Patos Lagoon estuary (Southern Brazil). Catalase and glutathione S-transferase activities (exposure biomarkers) and lipid peroxidation (effect biomarker) were analyzed in liver samples. Other two effect biomarkers were also studied: blood cells DNA damage (through comet assay and micronucleus test) and respiratory burst measurements. In a broad view, results point to an important seasonal variation of the biochemical biomarkers analyzed. However, data obtained clearly indicate that croakers collected in winter at the polluted site were subjected to a level of clastogenic agents sufficient to generate irreversible genetic damages (mutations) and impair the fish immune system.     

Variations of the Surface Wettability Index over the Tibetan Plateau During 1971-2005

Based on 1971-2005 monthly mean maximum/minimum temperature,wind speed,relative humidity,sunshine duration,and precipitation data at 25 stations over the Tibetan Plateau,a study of the largest potential evapotranspiration(LPE)is performed by using the Penman-Monteith model.The surface wettability index(SWI)is calculated and examined,together with its space distribution,interannual and seasonal variations,as well as associated causes.The results suggest that the annual area rainfall exhibits a pronounced increasing trend at 15.0 mm per decade; the annual LPE shows a different-degree decrease at-4.6-71.6 mm/10 yr.In the southwestern Ngari prefecture and Nyalam county,the annual SWI displays insignificant decline trends compared to increasing trends in other areas of Tibet(0.02-0.09 per decade).For Tibet,on average,the SWI experiences a noticeable rise at 0.04/10 yr,particularly in 1981-2005.On a seasonal basis,the SWI shows increasing trends,especially in summer.In the 1970s-1980s,the interannual variation is characterized mainly by lower temperature and lower humidity.From the 1990s,air temperature keeps on rising,leading to an appreciable increase in SWI,displayed as a type of warm and humid climate.The salient increases(decrease)of precipitation and relative humidity(mean temperature daily range)are the principal causes of the greatly enhanced SWI in the region.The pronounced decrease in mean wind and sunshine duration also plays an active role.     

青藏铁路建设冻土工程问题的深入研究和实践

青藏铁路开工建设以来的冻土工程问题研究, 在综合以往冻土学研究成果基础上, 针对冻土区大规模工程实践对冻土和冻土环境的影响特点, 冻土和冻土工程之间相互作用本质, 用系统工程论的观点, 以工程变形为冻土工程问题研究的综合目标, 抓住冻土工程问题的热学机理本质, 用工程热力结构作为解决问题的主要手段, 取得很好的实践效果. 同时把我国冻土工程问题研究和冻土工程建设提高到一个新的水平, 为建设世界一流的高原铁路奠定了坚实的技术基础.     

珠峰地区积雪变化与气候变化的关系

根据三次Landsat遥感数据,应用GIS空间分析方法,分析了1975-2000年珠峰地区定日县常年积雪变化特征,并探讨其与气候变化之间的关系。结果表明,1975-2000年间定日县内常年积雪总计减少了7.49％,减少面积为105.35 km2,主要发生在珠峰及其周围高大山体常年积雪覆盖的边缘地区,其中,海拔5 000～6 000 m之间减少最多,占减少总面积的70％左右。气温和降水量变化是导致常年积雪变化的主要因素,特别是在全球变暖的大背景下,珠峰地区的气温上升趋势是其主要驱动因子。气温升高导致珠峰及周围高大山脉边缘的冰川和常年积雪不断消融,加上1980年代的降水量相对较少,使得1975-1992年常年积雪面积不断减少;但1990年代后期降水量增加显著,研究区东南部海拔相对较低的区域有较多的积雪累积,1993-2000年常年积雪面积略有增加。     

POINTE AUTOMATIQUE*

The automatic picking of seismic sections replaces the slow and painstaking task of manual reflection plotting with rapid and economical processing by computer. Essentially, reflection picking is a decision-making problem which also can be considered as a sort of filtering. Mathematically this means multiplying the seismic data matrix by a more or less complex decision operator. For the sake of economy, we give an initial solution for simple cases which only require easily automatized decision-making criteria. We describe another more elaborate method for use in examining seismic phenomena which are more difficult to spot. The process used is based on the recognition of shapes and consists first of all of determining a series of characteristics capable of identifying each reflection on each trace and then of comparing these different characteristics from trace to trace so as to be able to judge the continuity or discontinuity of the reflections. Automatic picking thus leads to a schematic time-section in which only the horizons found by calculation are retained. An automatic migration program then transforms this time-section into a depth-section.     

Deposits and physical properties of pyroclastic density currents during complex Subplinian eruptions: the AD 472 (Pollena) eruption of Somma-Vesuvius, Italy

Small-scale pyroclastic density currents (PDCs) associated with the AD 472 (Pollena) eruption of Somma-Vesuvius, Italy, were generated by both magmatic and phreatomagmatic explosive fragmentation. The resulting deposits were emplaced under flow boundary conditions dominated by varying combinations of grain interaction, fluid escape and traction processes. Stratigraphic and lithofacies analysis of these PDCs offers a new perspective on the en masse versus progressive aggradation debate for PDC deposition. In particular, the analyses indicate that PDCs were density stratified with a basal underflow dominated by grain interactions. The underflows comprised trains of self-organized granular pulses of variable thickness and magnitude, depending on the overall particle concentration and fluid turbulence. A change in gradient between the upper and lower slopes of the volcano promoted deposition and the different pulses aggraded sequentially (stepwise). In this model each pulse stops en masse and the whole deposit aggrades progressively. Particle concentration, density, mean velocity, and flow height were assessed for the studied PDCs using differaent methods for massive and stratified deposits. The calculated mobility of the flows was 0·2 to 0·3, in the expected range for small-scale PDCs.     

Rapport (1966–1976) sun les Eléments en Traces Dans Trois Roches Standards Géochimiques Du CRPG . Basalte BR et Granites, GA et GH

Cinquième de la serie des rapports d'étude coopérative sur les standards géochimiques du CRPG, ce rapport est consacré exclusivement aux éeléments en traces dans trois éahantillons en circulation depuis 1963: les Granites GA et GH et le Basalte BR. La pré-sentation de plus de 2000 données analytiques réporties sur 50 éléments est accompagnée d'une évaluation statistique et critique, échantillon par éahmtillon et élément par élément. La discussion est menée dans le sens d'un dialogue direct avec I'utilisateur en nuançant et en hiérarchieant les valeurs que nous veoamnandons ou proposons. Quant à I'analyste practician, il trouvera une table des valeurs "utilisables" pour une trentaine d'éléments dans les trois échantillons de référence (Table 4). Rappelons que ces échantillons sont déjà bien caractérises en ce qui concerne leurs constituants majeurs et mineurs, grâce aux quatre rapports d'étude coopérative dont le dernier est paru en 1370.     

1960-2012年河西内陆河上游山区降水量变化及其区域性差异分析

基于我国河西内陆河流域有关水文、气象台站的观测数据,对1960年代以来河西走廊的石羊河、黑河、疏勒河三大内陆河水系上游山区降水变化特征、趋势及区域时空变化差异进行了分析.结果表明：受全球变暖的影响,石羊河、黑河、疏勒河流域上游的降水量年代际、年际及季节性的变化总体上呈增加的态势,但不同区域降水增幅存在着一定的差异.其中,1960年代,位于祁连山东部的石羊河水系上游山区、中部的黑河水系上游山区及西部的疏勒河水系上游山区普遍少雨;1970年代,石羊河山区降水偏多并持续至今,黑河、疏勒河水系上游山区则降水偏少;1980年代,三大水系上游山区均多雨;1990年代的黑河、疏勒河山区和2000年代的三大水系上游山区均多雨;2010年以来,黑河山区降水偏少,石羊河与疏勒河山区降水均偏多.相对而言,位于祁连山西部山区的疏勒河水系上游年降水量与夏季降水量的增长较为显著.     

Toxicity assessment of New Zealand and Pacific dinoflagellates Ostreopsis and Gambierdiscus (Dinophyceae) extracts using bioassays

The dinoflagellate genus Ostreopsis produces palytoxin-like compounds (PLTXs) and the genus Gambierdiscus produces ciguatoxins (CTXs) and maitotoxin (MTX). Human illness has been recorded following the consumption of CTX-contaminated finfish. Their effects on the flora and fauna in the environment are largely unexplored. Toxin profiles of extracts of Ostreopsis and Gambierdiscus isolates from the Pacific region were characterised using liquid chromatography tandem mass spectrometry. Sea urchin (Evechinus chloriticus) fertilisation was unaffected by any algal extracts, but extracts containing maitotoxin-3 (MTX-3, but not MTX or CTXs), or with high concentrations of PLTXs, were toxic to urchin larval development. Gambierdiscus extracts containing CTXs elicited toxic responses in zebrafish (Danio rerio) embryo toxicity assays; extracts containing only MTX-3 elicited a limited response. Ostreopsis extracts containing PLTXs caused no response. The results demonstrate potential impacts of toxic dinoflagellates on larval organisms and the potential of embryonic assays as toxicity screening tools.