PBDEs in the blubber of marine mammals from coastal areas of São Paulo, Brazil, southwestern Atlantic     

Yogui GT  Santos MC  Bertozzi CP  Sericano JL  Montone RC 《Marine pollution bulletin》2011,62(12):2666-2670

Limited information is available in the literature on the levels of brominated flame retardants in the southern hemisphere. This study presents concentrations of polybrominated diphenyl ethers (PBDEs) in the blubber of small cetaceans from the coast of São Paulo (Brazil), southwestern Atlantic. PBDE levels were highest in Stenellafrontalis (770 ng g⁻¹ lipid) followed by Stenobredanensis (475 ng g⁻¹ lipid), Sotaliaguianensis (65.6 ng g⁻¹ lipid), Tursiopstruncatus (64.2 ng g⁻¹ lipid) and Pontoporiablainvillei (60.3 ng g⁻¹ lipid). In general, continental shelf individuals exhibited higher contamination than inshore animals. This might be related to larger prey items consumed by continental shelf dolphins. The pattern of contamination indicates that Penta-BDE commercial mixtures are a major source of PBDEs to top predators in the southwestern Atlantic. Congeners found in Octa-BDE formulations were not detected in the investigated animals.  相似文献   

Behavioral effects of titanium dioxide nanoparticles on larval zebrafish (Danio rerio)     

Chen TH  Lin CY  Tseng MC 《Marine pollution bulletin》2011,63(5-12):303-308

In this study, zebrafish embryos were exposed to titanium dioxide nanoparticles (TiO2 NPs at 0.1, 0.5, 1, 5, 10 mg/L or control) from fertilization to free swimming stage. Hatchability, survival, and malformation rate were not affected by TiO2 NPs at these exposure levels. However, larval swimming parameters, including average and maximum velocity and activity level were significantly affected by TiO2 NPs. Co-exposure to either the glutathione precursor, N-acetylcysteine (NAC), or the glutathione synthesis inhibitor, buthionine sulfoximine (BSO), did not significantly alter the behavioral effects resulting from TiO2 NPs, suggesting that other factor(s) besides oxidative stress may contribute to the behavioral toxicity of TiO2 NPs. Our study also demonstrated that the behavioral endpoints were more sensitive than the others (e.g., hatchability and survival) to detect toxicity of TiO2 NPs on developing fish.  相似文献   

仙游井水位在2017年7月打井干扰前后频带响应的特性变化          下载免费PDF全文

樊俊屹  刘春国  陶志刚 《地震工程学报》2021,43(5):1123-1128,1141

利用小波变换、相关分析、调和分析方法,分析仙游井水位在2017年7月打井抽水干扰前后各频带的变化特征。结果显示：打井抽水干扰严重时,水位的全频率影响显著;趋于稳定后中频带基本恢复,但低频带仍然存在多个强信号,M₂潮汐应变响应能力略有下降,表明仙游井水位中频带在受干扰后是应力变化的有效监测波段。文章研究方法和结果可为水位资料干扰分析与异常提取提供参考。  相似文献   

Intra- and inter-specific variability in total and methylmercury bioaccumulation by eight marine fish species from the Azores   总被引：1，自引：1，他引：0  

Magalhães MC  Costa V  Menezes GM  Pinho MR  Santos RS  Monteiro LR 《Marine pollution bulletin》2007,54(10):1654-1662

We relate fish biological and ecological characteristics to total and organic mercury concentrations to determine whether accumulation is influenced by trophic level, Hg concentration in the diet, and vertical distribution. Levels of total mercury and methylmercury were determined in the muscle tissue of eight species of fish: Pagellus acarne, Trachurus picturatus, Phycis phycis, P. blennoides, Polyprion americanus, Conger conger, Lepidopus caudatus and Mora moro, caught in the Azores. All such fishes are commercially valuable and were selected to include species from a wide range of vertical distributions from epipelagic (<200 m) to mesopelagic (>300 m) environments. Methylmercury was the major form accumulated in all species, comprising an average of 88.1% of total mercury. Concentrations of mercury (total and methylmercury) increased with age, length and weight. Based on data from other studies, mercury concentrations in fish diet were estimated. Mercury levels in food ranged from 0.08 to 0.32 ppm, dry weight. Hg concentrations in the food and in muscle tissue from different species were positively correlated. Total Hg levels in the muscles were approximately nine times those estimated in food. Total mercury concentrations in muscle were positively correlated with both trophic level and median depth. Such enhanced mercury bioaccumulation in relation to depth appears to be determined primarily by concentrations in food and ultimately by water chemistry, which controls mercury speciation and uptake at the base of the food chain.  相似文献   

神户地震的地下水化学前兆变化     

Tsuno.  U 刘春国 《地震地质译丛》1996,18(2):41-43

  相似文献   

三维后方交会     

Brea.  MC 王欣 《黑龙江测绘》1996,19(1):43-47

传统的二维后方交会有３个已知点，在未知点上观测两上水平角以求得未知点坐标，或有两上已知点，在未知点上观测一个水平角和一个方位角也可求得未知坐标。本文所要叙述的是在未知点观测一个水平角和两个垂直角，就要计算出它的三维坐标。  相似文献   

从泥岩中分离出重矿物的方法     

迪安.  MC  石宏仁 《国土资源信息化》1996,(5):31-33

  相似文献   

Assessment of toxicological status of a SW Mediterranean segment population of striped dolphin (Stenella coeruleoalba) using skin biopsy     

Fossi MC  Marsili L  Lauriano G  Fortuna C  Canese S  Ancora S  Leonzio C  Romeo T  Merino R  Abad E  Jiménez B 《Marine environmental research》2004,58(2-5):269-274

Various studies have revealed high concentrations of contaminants such as organochlorines (OCs) and heavy metals in Mediterranean cetaceans. A geographical trend of contamination (PCBs and DDTs) has been found for striped dolphin (Stenella coeruleoalba). In this study we used a non-lethal approach (skin biopsy) to investigate bioaccumulation of OCs, including polychlorobiphenyls (PCBs), DDTs, polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), trace elements (Hg, Cd, Pb) and CYP1A activity (BPMO) in nine striped dolphins sampled in the Aeolian area (Sicily - Italy) in summer 2002. The arithmetic mean value of BPMO activity in this group was 43.46 AUF/g tissue/h. This value is approximately 3 times and 5 times lower, respectively, than the value found in the Ionian and in the Ligurian groups. Skin biopsies of striped dolphins emerged as a suitable material for assessing the toxicological status of the various Mediterranean groups.  相似文献   

含氟初始风化水化学组成的模型研究   总被引：2，自引：0，他引：2  

刘春国  段长春 《长春地质学院学报》1995,25(4):423-427

在我国“三北”地区，浅层地下水中高氟苏打水分布广泛。本文利用和简化了Ｈｅｌｇｅｓｏｎ风化模型，以吉林省乾安地区为例，对含氟初始风化水化学组成作了研究和计算；探讨了二氧化碳滴定作用对风化过程的影响，从而定量确定了高氟水的成因模型。  相似文献   

P波路径从西伯利亚向挪威衰减     

Walck  MC 《地震译文集》1991,(1):36-37,66

  相似文献