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1.
《Marine pollution bulletin》2012,64(5-12):297-302
Heavy oil (HO) on the sea surface penetrates into fish eggs and prevents the normal morphogenesis. To identify the toxicological effects of HO in the context of the egg types, we performed exposure experiments using floating eggs and sinking eggs. In the course of development, HO-exposed embryos of floating eggs showed abnormal morphology, whereas early larva of the sinking eggs had almost normal morphology. However, the developing peripheral nervous system of sinking eggs showed abnormal projections. These findings suggest that HO exposed fishes have problems in the developing neurons, although they have no morphological malformations. Through these observations, we conclude that HO is strongly toxic to floating eggs in the morphogenesis, and also affect the neuron development in both floating and sinking eggs. 相似文献
2.
《Marine pollution bulletin》2009,58(6-12):524-528
It is well known that heavy oil (HO) on the sea surface causes serious problems in the aquatic environment. In particular, some species of teleosts which develop on the sea surface are thought to be affected by the HO which flows out from tankers or coastal industry. However, the toxicological effects of HO are not fully understood. We performed exposure experiments using the Pleuronectiformean fish, spotted halibut (Verasper variegatus), which is an important fishery resource in Japan. In course of the development, HO-exposed embryos showed remarkable delay in developmental processes including somite formation. We further observed abnormal development of the head morphology. Notably, treated embryos had relatively small eyes and craniofacial structures. These findings strongly suggest that HO seriously affects the cell proliferation and differentiation of the embryo. In addition, HO-exposed embryos showed abnormal neuronal development. We also performed the exposure in the larval stage. Treatment of post-hatching larvae with HO resulted in significantly greater mortality compared with controls. Through these observations, we finally conclude that HO is strongly toxic to halibut in their early life stages. 相似文献
3.
Yasunori Murakami Shin-Ichi Kitamura Kei Nakayama Satoru Matsuoka Hideo Sakaguchi 《Marine pollution bulletin》2008,57(6-12):524
It is well known that heavy oil (HO) on the sea surface causes serious problems in the aquatic environment. In particular, some species of teleosts which develop on the sea surface are thought to be affected by the HO which flows out from tankers or coastal industry. However, the toxicological effects of HO are not fully understood. We performed exposure experiments using the Pleuronectiformean fish, spotted halibut (Verasper variegatus), which is an important fishery resource in Japan. In course of the development, HO-exposed embryos showed remarkable delay in developmental processes including somite formation. We further observed abnormal development of the head morphology. Notably, treated embryos had relatively small eyes and craniofacial structures. These findings strongly suggest that HO seriously affects the cell proliferation and differentiation of the embryo. In addition, HO-exposed embryos showed abnormal neuronal development. We also performed the exposure in the larval stage. Treatment of post-hatching larvae with HO resulted in significantly greater mortality compared with controls. Through these observations, we finally conclude that HO is strongly toxic to halibut in their early life stages. 相似文献
4.
Murakami Y Kitamura S Nakayama K Matsuoka S Sakaguchi H 《Marine pollution bulletin》2008,57(6-12):524-528
It is well known that heavy oil (HO) on the sea surface causes serious problems in the aquatic environment. In particular, some species of teleosts which develop on the sea surface are thought to be affected by the HO which flows out from tankers or coastal industry. However, the toxicological effects of HO are not fully understood. We performed exposure experiments using the Pleuronectiformean fish, spotted halibut (Verasper variegatus), which is an important fishery resource in Japan. In course of the development, HO-exposed embryos showed remarkable delay in developmental processes including somite formation. We further observed abnormal development of the head morphology. Notably, treated embryos had relatively small eyes and craniofacial structures. These findings strongly suggest that HO seriously affects the cell proliferation and differentiation of the embryo. In addition, HO-exposed embryos showed abnormal neuronal development. We also performed the exposure in the larval stage. Treatment of post-hatching larvae with HO resulted in significantly greater mortality compared with controls. Through these observations, we finally conclude that HO is strongly toxic to halibut in their early life stages. 相似文献
5.
Kawaguchi M Song JY Irie K Murakami Y Nakayama K Kitamura S 《Marine pollution bulletin》2011,63(5-12):356-361
It has been well known that oil spills cause serious problems in the aquatic organisms. In particular, some species of teleosts, which develop on the sea surface thought to be affected by heavy oil (HO). During the embryogenesis, the nervous system is constructed. Therefore, it is important to study the toxicological effects of HO on the developing neurons. We exposed HO to eggs of Japanese flounder (Paralichthys olivaceus) and investigated the neural disorder. In larvae exposed by HO at the concentration of 8.75 mg/L, the facial and lateral line nerves partially entered into the incorrect region and the bundle was defasciculated. Furthermore, in the HO-exposed larvae, Sema3A, a kind of axon guidance molecule, was broadly expressed in second pharyngeal arch, a target region of facial nerve. Taken together, we suggested the possibility that the abnormal expression of Sema3A affected by HO exposure causes disruption of facial nerve scaffolding. 相似文献
6.
《Marine pollution bulletin》2012,64(5-12):356-361
It has been well known that oil spills cause serious problems in the aquatic organisms. In particular, some species of teleosts, which develop on the sea surface thought to be affected by heavy oil (HO). During the embryogenesis, the nervous system is constructed. Therefore, it is important to study the toxicological effects of HO on the developing neurons. We exposed HO to eggs of Japanese flounder (Paralichthys olivaceus) and investigated the neural disorder. In larvae exposed by HO at the concentration of 8.75 mg/L, the facial and lateral line nerves partially entered into the incorrect region and the bundle was defasciculated. Furthermore, in the HO-exposed larvae, Sema3A, a kind of axon guidance molecule, was broadly expressed in second pharyngeal arch, a target region of facial nerve. Taken together, we suggested the possibility that the abnormal expression of Sema3A affected by HO exposure causes disruption of facial nerve scaffolding. 相似文献
7.
Yuki Sugahara Masahumi Kawaguchi Tatsuya Itoyama Daisuke Kurokawa Yasuhiko Tosa Shin-Ichi Kitamura Itsuki C. Handoh Kei Nakayama Yasunori Murakami 《Marine pollution bulletin》2014
Spills of heavy oil (HO) have an adverse effect on marine life. We have demonstrated previously that exposure to HO by fertilized eggs of the pufferfish (Takifugu rubripes) induces neural disruption and behavioral abnormality in early-hatched larvae. Here, two kinds of polycyclic aromatic hydrocarbons, pyrene and phenanthrene, were selected to examine their toxic effects on larval behavior of another pufferfish species (T. niphobles). Larvae exposed to pyrene or phenanthrene exhibited no abnormalities in morphology. However, those exposed to pyrene but not phenanthrene swam in an uncoordinated manner, although their swimming distance and speed were normal. The optic tectum, a part of the midbrain, of pyrene-exposed larvae did not grow to full size. Thus, these findings are indicated that pyrene might be a contributor to the behavioral and neuro-developmental toxicity, although there is no indication that it is the only compound participating in the toxicity of the heavy oil mixture. 相似文献
8.
Six plastic/rubber materials commonly encountered in marine debris and beach litter were studied under Biscayne Bay (Florida, USA) exposure conditions to determine the effect of fouling on buoyancy. Studies under restricted floating, and restricted submerged exposure conditions suggest that most plastic samples undergo fouling to an extent to cause the sample to be negatively buoyant in sea water. Rapid defouling of the submerged fouled samples was observed. The findings suggest that free-floating plastics at sea may, under certain conditions, undergo fouling-induced sinking followed by resurfacing as floating debris. 相似文献
9.
Denovan Chauveau Anne-Morwenn Pastier Gino de Gelder Laurent Husson Christine Authemayou Kevin Pedoja Sri Yudawati Cahyarini 《地球表面变化过程与地形》2024,49(2):549-566
The morphology of coastal sequences provides fundamental observations to unravel past sea level (SL) variations. For that purpose, converting morphometric observations into a SL datum requires understanding their morphogenesis. The long-lasting sequence of coral reef terraces (CRTs) at Cape Laundi (Sumba Island, Indonesia) could serve as a benchmark. Yet, it epitomizes a pitfall that challenges the ultimate goal: the overall chronology of its development remains poorly constrained. The polycyclic nature of the terraces, involving marine erosion and reoccupation of old coral colonies by more recent ones hinders any clear assignment of Marine Isotope Stages (MIS) to specific terraces, in particular the reference datum corresponding to the last Interglacial maximum (i.e., MIS 5e). Thus, to overcome these obstacles, we numerically model the genesis of the sequence, testing a range of eustatic SL (ESL) reconstructions and uplift rates, as well as exploring the parameter space to address reef growth, erosion and sedimentation. A total of 625 model runs allowed us to improve the morpho-chronological constraints of the coastal sequence and, more particularly, to explain the morphogenesis of the several CRTs associated with MIS 5e. Our results suggest that the lowermost main terrace was first constructed during the marine transgression of MIS 5e and was later reshaped during the marine regression of MIS 5e, as well as during the MIS 5c and MIS 5a highstands. Finally, we discuss the general morphology of the sequence and the implications it may have on SL reconstructions. At Cape Laundi, as elsewhere, we emphasize the necessity of addressing the development of CRT sequences with a dynamic approach, that is, considering that a CRT is a landform built continuously throughout the history of SL oscillations, and not simply during a singular SL maximum. 相似文献
10.
Ercilla G Córdoba D Gallart J Gràcia E Muñoz JA Somoza L Vázquez JT Vilas F;Prestige Group 《Marine pollution bulletin》2006,53(5-7):208-219
The tanker Prestige sank off NW Iberia on the 19th November 2002. The stern and bow of the Prestige wreck are located on the southwestern edge of the Galicia Bank, at 3565 m and 3830 m water depths, respectively. This bank is a structural high controlled by major faults with predominant N-S, NNE-SSW, and NNW-SEE trends. It is characterized by moderate to low seismic activity. The faults have controlled the local depositional architecture, deforming, fracturing, relocating and distributing sediments since the Valangian (early Cretaceous). The Prestige sinking area corresponds to an asymmetric half-graben structure with a N-S trend, which conditions the present-day morphology. The faulted flank outcrops and its activity and erosion have favoured the occurrence of mass-movements (slumps, slump debris, mass-flows and turbidity currents), building valleys and depositional lobes. Nearsurface sediments comprise mostly terrigenous and biogenous turbiditic muds and sands with a minor presence of hemipelagic muds, except on the fault scarp where pelagites predominate. Potential geological hazards resulting from tectonic and sedimentary processes affect almost the entire Prestige sinking area. 相似文献
11.
T.I. Balkas I. Salihoǧlu A.F. Gaines M. Sunay J. Matthews 《Marine pollution bulletin》1982,13(6):202-205
Tar balls, according to their densities, the prevailing temperature and their degree of weathering, are observed as floating, sinking, or are washed onto the beaches in the marine environment. To characterize the differences between floating and sunken tar balls, samples were analysed by IR, H-nmr, GC and GC/MS techniques. Hexane, benzene and methanol solubilities as well as densities were measured. The degree of weathering of the tar balls was investigated in terms of the losses of hydrocarbons. The ratio of paraffinic/aromatic hydrocarbon concentrations was calculated by IR and H-nmr whereas pristane/phytane ratios were estimated from GC measurements. The comparison of some high molecular weight, but minor, components between the major was obtained from GC/MS measurements. 相似文献
12.
Ken Hatayama 《Journal of Seismology》2008,12(2):255-263
The 2003 Tokachi-oki earthquake (M
w 8.0) in northern Japan generated large-amplitude long-period (4–8 s) ground motions in the Yufutsu sedimentary basin, causing
severe damage to seven large oil storage tanks with floating roof structures because of severe sloshing of oil. The 30,000–40,000-m3 tanks having suffered the severe damage such as fires and sinking of floating roofs experienced the sloshing with large amplitudes
exceeding 3 m in which the fundamental mode was predominant. The second mode of sloshing was also excited in the 110,000-m3 tanks in which their floating roofs sank into oil, indicating that the higher modes of sloshing as well as the fundamental
mode should be considered in damage prediction. The strong ground motion recordings demonstrated the earthquake dependency
of predominant periods and the substantial spatial variation of the long-period shaking observed within the Yufutsu basin,
meaning the necessity of source- and site-specific prediction of long-period strong ground motions. The two-dimensional numerical
modeling suggested the importance of detailed structures of soft near-surface sediments as well as deep basin structure for
accurate prediction of long-period strong ground motions in deep sedimentary basins. 相似文献
13.
The eggs of Cyprinus carpio were irradiated by 5 different strengths: 0.0258, 0.129, 0.258, 0.516 and 1.29 C/kg (100, 500, 1000, 2000 and 5000 R) of γ-rays in the batches of 50 fertilized eggs. The activities of eggs and hatched fries were noted after irradiation doses. The hatching percentages of the eggs were reported for each group. The percentage of hatched eggs of Cyprinus carpio after radiation doses of 0.0258, 0.129, 0.258, 0.516 and 1.29 C/kg (100, 500, 1000, 2000 and 5000 R) was 30%, 24%, 28%, 30%, and 34%, respectively. The 50% mortality period of fries for the above strengths of the γ-rays was 8 days, 7 days, 6 days. 4 days and 4 days, respectively. The survival period of the fries was 11 days, 9 days, 8 days, 7 days and 6 days, respectively. All fries hatched from the eggs irradiated by γ-rays showed early hatching, a higher percentage of mortality, a retarded and abnormal development of the body. A statistical analysis of the results by the correlation coefficient also proved that the hatching percentages of the fries and the survival period of fries are directly proportional to the strength of the γ-rays and inversely proportional to the strength of γ-rays, respectively. 相似文献
14.
Stress sensitivity of stylolite morphology 总被引：1，自引：0，他引：1
Marcus Ebner Daniel Koehn Renaud Toussaint François Renard Jean Schmittbuhl 《Earth and Planetary Science Letters》2009,277(3-4):394-398
Stylolites are rough surfaces that form by localized stress-induced dissolution. Using a set of limestone rock samples collected at different depths from a vertical section in Cirque de Navacelles (France), we study the influence of the lithostatic stress on the stylolites morphology on the basis of a recent morphogenesis model. We measured the roughness of a series of bedding-parallel stylolites and show that their morphology exhibits a scaling invariance with two self-affine scaling regimes separated by a crossover-length (L) at the millimeter scale consistent with previous studies. The importance of the present contribution is to estimate the stylolite formation stress σ from the sample position in the stratigraphic series and compare it to the crossover-length L using the expected relationship: L ～ σ ?2. We obtained a successful prediction of the crossover behavior and reasonable absolute stress magnitude estimates using relevant parameters: depth of stylolite formation between 300 to 600 m with corresponding normal stress in the range of 10–18 MPa. Accordingly, the stylolite morphology contains a signature of the stress field during formation and we thus suggest that stylolites could be used as paleo-stress gauges of deformation processes in the upper crust. 相似文献
15.
Heavy oil exposure induces high moralities in virus carrier Japanese flounder Paralichthys olivaceus
The relationship between chemical exposure and disease outbreak in fish has not been fully defined due to the limitations of experimental systems (model fish and pathogens). Therefore, we constructed a system using the Japanese flounder, Paralichthys olivaceus, and viral haemorrhagic septicemia virus (VHSV), and evaluated it by heavy oil (HO) exposure. The fish were exposed to HO at 0.3, 0.03, 0.003, and 0 g/L following VHSV infection at doses of 10(2.5) or 10(3.5) tissue culture infectious dose (TCID)50/fish. As a result, groups given the dual stressors showed more than 90% mortality. Although VHSV infection at 10(2.5) and 10(3.5) TCID50/fish without HO exposure also induced high mortality, at 68.8% and 81.3%, respectively, HO exposure induced faster and higher mortality in the virus carrier fish, indicating that chemical stressors raise the risk of disease outbreak in fish. The experimental system established in this study could be useful for chemical risk assessment. 相似文献
16.
永登5.8级地震极震区黄土微结构孔隙性的定量研究 总被引：1，自引：0，他引：1
通过电镜扫描手段和计算机图像处理,对1995年永登5．8级地震极震区遭受地震影响和未遭受地震影响的黄土微结构变化的各项指标进行了对比试验和分析,并将分析结果绘成受震与未受震两种孔隙分布曲线。从这些曲线可以看出,不同地点的黄土孔隙分布特征不同;同一深度不同地点的孔隙分布亦有明显差异。对未受震(粒状架空孔隙结构)与受震(粒状镶嵌孔隙结构)黄土的微观结构进行了定量处理,其分析结果较好地解释了土体的工程性质。同时介绍了黄土微结构研究的方法和要求,通过对黄土微观结构的定量处理,揭示了黄土震陷性与黄土孔隙含量所占比例大小的内在关系,达到了确定黄土场地震陷量的目的,验证了利用微结构研究黄土结构变化的可行性。 相似文献
17.
Effects of cadmium on the fertilizing capability of spermatozoa, dynamics of the first cleavage and pluteus formation in the sea urchin, Anthocidaris crassispina, were investigated. Exposure to cadmium concentrations of 0.32, 0.56, 1.0, 1.8, 3.2, 5.6 and 10.0 mg l−1 for 30 min caused a significant adverse effect on the fertilizing capability of spermatozoa (EC50=1.7 mg l−1). For the first cleavage kinetics assay, eggs were pre-exposed to 0, 0.18, 0.32, 0.56, 1.0, 1.8, 3.2 and 5.6 mg l−1 of cadmium for 30 min. Fresh sperms of fixed concentrations were then added to the eggs and the percentage of divided zygotes estimated. Concentration-dependent toxic effects on the dynamics of the first cleavage in A. crassispina were observed between 0.18 and 5.6 mg l−1 cadmium. Calculation of EC50 values by probit analysis at different stages of the first cleavage revealed that EC50 values increased gradually from 0.37 mg l−1 at the beginning to 2.24 mg l−1 at the end of the cleavage process. Different larval classes (normal, abnormal and retarded plutei, preplutei, dead embryos/larvae) of A. crassispina obtained from eggs pre-treated with cadmium for 30 min and then exposed to cadmium throughout embryogenesis were also examined. The percentage of abnormal plutei was significantly higher than that of the control at 0.56 mg l−1 cadmium and higher. The 48 h EC50 calculated for the number of normal plutei was 1.5 mg l−1. A χ2-test revealed significant changes in the distribution of proportions of different larval classes only at cadmium concentrations 1.8 mg l−1. At 5.6 mg l−1 of cadmium, small malformed plutei, and oval embryos with rudimentary skeleton, poorly differentiated intestines and no mouth (pre-pluteus stage) were observed. The relative sensitivity of various end points to cadmium is also compared and discussed. 相似文献
18.
19.
Dreamlet偏移成像目的是探索一类能够对地震波场和单程波传播算子同时分解和压缩的理论和方法,也即实现在压缩域的传播与成像、地震数据在时间和空间的非平稳性质,决定了要实现地震数据的有效稀疏表示,分解方法必须在时间和空间上同时具有局域化性质.Dreamlet由时间和空间局部分解原子的张量积构成,可以看作一种脉冲-小波束形式的波场分解原子.时空局域化的dreamlet单程波传播算子在对波场沿深度方向延拓时,地震数据在时间轴上总是向同一方向流动.随着深度的增加,部分用于成像浅层结构的数据归位至其空间位置后被dreamlet算子丢弃,波场的有效记录时间变短,每一步用于波场延拓的计算量也相应下降.为了充分发挥这一优势,本文介绍dreamlet传播算子与观测系统沉降法偏移相结合的理论与方法.观测系统沉降法偏移每一步都将记录到的所有数据向下延拓,沉降后的波场等效于把源和检波器都放置在目标深度所能接收的反射数据.Dreamlet观测系统沉降过程只保留用于成像观测系统下部地质结构的有效数据,自动丢弃已经用于成像观测系统上部而对下部成像没有贡献的信号.本文通过二维SEG/EAGE叠后和Marmousi叠前数据算例展示了dreamlet传播算子应用于观测系统沉降法偏移的这一特点.数值算例结果显示,在不影响成像质量的前提下,该偏移方法能够有效减少传播数据量,为发展一种快速高效的偏移方法提供了新的思路. 相似文献
20.
本文将地震释放能量作为地震活动场的基本要素, 采用自然正交函数展开方法, 系统研究2014年景谷6.6级地震震中区域地震活动能量场的时空特征。 结果表明, 景谷6.6级地震前能量场的前4个主要特征值对应的典型能量场时间因子都出现明显上升变或下降异常, 空间等值线形成局部能量高值异常危险区, 可能是景谷 6.6级地震空间异常的中短期特征。 我们还进一步研究了景谷6.6级地震前后空间异常随时间的演变, 给出了异常发展变化模式, 最后应用研究地震资料的累积次数从物理角度解释异常形成的机制。 相似文献