Effects of heavy oil in the developing spotted halibut, Verasper variegatus

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.     

Effects of heavy oil in the developing spotted halibut, Verasper variegatus

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.     

A flare model deduced from Hinotori and millimeterwave interferometer observations

The -ray and white-light flare of 13 May, 1981 is used for a study of spatial distributions of energetic electrons and high-temperature plasma.     

乌鲁木齐天文站在月球探测同波束干涉测量中的作用

首先简要介绍同波束干涉测量技术,随后叙述中国科学院国家天文台乌鲁木齐天文站在2008年成功完成了约200 h日本月球卫星SELENE同波束较差甚长基线干涉测量,并阐述乌站在此次VLBI中的作用。给出利用SELENE的观测数据,分析、解算出乌站25 m天线与日本VERA网相关台站基线Rstar、Vstar的S1、S2、S3、X频段的较差相关相位、较差相关相位残差,以及对各频段的较差相关相位、较差相关相位残差比对,最后获得较差相位时延。结果显示,同波束甚长基线干涉测量比传统VLBI观测得到的群时延精度提高了1～2个量级。     

The spatial and temporal distributions of spheroidal carbonaceous particles from sediment core samples from industrial cities in Japan and China

Spheroidal carbonaceous particles (SCPs) are produced by the high-temperature combustion of fossil fuels and emitted in to the atmosphere. The distribution and concentration of SCPs in sediments have been used as a proxy for the distribution of pollutants emitted to the atmosphere. However, the effect on the distribution of SCPs due to industrial activity at nearby industrial cities is yet to be quantified. To clarify the origin of SCPs of ~20 μm in size that are preserved in sediments, we evaluated the abundance, surface morphology, and chemical composition of SCPs in sediment core samples recovered from industrial cities in Japan (Tokyo, Osaka, and Nagasaki) and China (Beijing), with the cities being located at least ~500 km away from each other. Vertical profiles of SCP concentration in sediment cores from the Japanese cities and Beijing are different, reflecting the contrasting industrial histories of the two countries. The SCPs from different cities show contrasting morphological and chemical characteristics, suggesting that ~20 μm SCPs in sediments from the industrial cities could represent the local combustion history in detail, as the influx of local SCPs is dominant at such sites.     

http://www.sciencedirect.com/science/article/pii/S1674987112001028

A study on the effect of the solar ultra-violet radiation on the human skin fibroblast cells revealed that the production of matrix metalloproteinase-2 was inhibited by the radiation.A CO2 incubator connected by optical fibers to a reflector telescope for collecting the solar light was built at Syowa station by the 49th Japanese Antarctica Research Expedition.The direction of the telescope was continuously controlled by a sun-tracker to follow the movement of the Sun automatically.The intensity of the collected light was monitored by a portable spectrophotometer housed inside.The human skin fibroblast cells were incubated in the CO2 chamber to investigate the effect of the solar radiation at Syowa station and were compared with those reference experiments at a laboratory in Japan.The results showed cell damage by strong UV radiation.The production of matrix metalloproteinase-2 was prompted by the moderate UV-B,but was inhibited by the strong UV-B radiation,as studied under laboratory conditions in Japan.The effect of strong solar radiation at Syowa station involving the radiation of UV-B region was estimated to be of the same extent of the radiation caused by an artificial UV-B light with the intensity more than 50 mJ/cm2.     

Inundation flow velocity of tsunami on land

An estimation of tsunami inundation flow velocity is one of the most challenging issues among tsunami research. Based on field data of inundation depth and inundation flow velocity u estimated using Bernoulli's theorem and inundation depth, fundamental characteristics of the relationship between inundation flow velocity and inundation depth are examined. Fundamental characteristics of the velocity coefficient where g is gravitational acceleration, h_f and h_r are inundation depths at the front and the back of structures such as a rectangular building with vertical walls, respectively) implicitly included in the relationship are examined through hydraulic experiments. As a result, C_v = 0.6 is recommended as its simple and practical value. It is confirmed through these examinations that the Froude number, defined by where , ranges 0.7–2.0, and when C_v = 0.6 is adopted this Froude number ranges 0.42–1.2. By using the relationship and C_v = 0.6, two simple and practical relationships are presented for two cases where inundation flow velocity exerts the largest or the smallest fluid force on structures. These relationships can be used to roughly grasp the practical side of tsunami damage, and estimate fluid force acting on individual structures, moving velocity and collision force of floating objects and sediment transport such as boulder and sand. Fundamental characteristics of the waterline (tsunami trace) distribution around/on the typical object model (square pillar, corn and column) are also examined through steady flow experiments, and it is confirmed that the maximum and the minimum values of h_f/h₀ in the full type model of the square pillar are almost the same as those of h_f/h_r obtained by field surveys where h₀ is uniform flow depth. It is also confirmed that h_r ? h₀ when the Froude number, defined by where u₀ is uniform flow velocity, is much less than 1.0. Using a newly defined velocity coefficient, tsunami inundation flow velocity on land can be estimated practically and would be useful for checking proposed sediment transport models that are now being developed by tsunami geologists.