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11.
Jun Yamamoto Miyuki Hirose Tetsuya Ohtani Katashi Sugimoto Kazue Hirase Nobuo Shimamoto Tsuyoshi Shimura Natsumi Honda Yasuzumi Fujimori Tohru Mukai 《Marine Biology》2008,153(3):311-317
The fate of the giant jellyfish Nemopilema nomurai after death was examined in the southwest Sea of Japan. The density of dead jellyfish was greater than that of live animals.
The dead animals are heavier than the Japan Sea Proper Water which occurs deeper than 200 m, suggesting that dead jellyfish
sink to the sea floor. The sea floor survey, conducted with a towed video tape recorder (VTR) monitoring system between mid
September and mid October, observed a total of 138 jellyfish during 28 of 29 operations. The density of carrion ranged between
0.2 and 5.1 individuals/1,000 m2 (mean ± SE = 1.1 ± 0.2). Ophiuroids occurred abundantly at 23 jellyfish carcasses and a sea anemone was observed attached
to five carcasses. The VTR surveys confirmed that carrion sinks to the sea floor not only during the winter, the normal end
of life for medusae, but also during the fall. A trap survey baited with medusae was also employed, and four different species
were sampled with the traps: the snow crab (Chionoecetes opilio), a shrimp (Pandalopsis japonica), the ivory shell (Buccinum striatissimum) and an ophiuroid (Ophiura sarsii). Much of the trap bait remained (49–68% weight-mean = 60.3%) during the 23 h soak-time, and the reduction in weight was
greater than that observed by bacterial decomposition, suggesting benthic animals consume dead organisms. The present study
indicates that dead N. nomurai sink to the sea floor continuously and were subsequently consumed by benthic scavengers. 相似文献
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Tomohiko Isobe Shohei P. Ogawa Rina Sugimoto Karri Ramu Agus Sudaryanto Govindan Malarvannan Gnanasekaran Devanathan Babu Rajendran Ramaswamy Natesan Munuswamy Deavaraj Sankar Ganesh Jeyaraj Sivakumar A. Sethuraman V. Parthasarathy Annamalai Subramanian Jennifer Field Shinsuke Tanabe 《Environmental monitoring and assessment》2013,185(7):5627-5637
Perchlorate contamination was investigated in groundwater and surface water from Sivakasi and Madurai in the Tamil Nadu State of South India. Sensitive determination of perchlorate (LOQ?=?0.005 μg/L) was achieved by large-volume (500 μL) injection ion chromatography coupled with tandem mass spectrometry. Concentrations of perchlorate were <0.005–7,690 μg/L in groundwater (n?=?60), <0.005–30.2 μg/L in surface water (n?=?11), and 0.063–0.393 μg/L in tap water (n?=?3). Levels in groundwater were significantly higher in the fireworks factory area than in the other locations, indicating that the fireworks and safety match industries are principal sources of perchlorate pollution. This is the first study that reports the contamination status of perchlorate in this area and reveals firework manufacture to be the pollution source. Since perchlorate levels in 17 out of 57 groundwater samples from Sivakasi, and none from Madurai, exceeded the drinking water guideline level proposed by USEPA (15 μg/L), further investigation on human health is warranted. 相似文献
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M. N. A. Bhuiyan Yasuaki Ito Toyoko Demachi Keizo Sugimoto Arata Katayama Tatsuya Hasegawa 《Journal of Material Cycles and Waste Management》2014,16(2):227-238
Hydrothermal treatment of model food garbage focusing on the effects of additional foreign matter has been performed in subcritical conditions as a pretreatment for the next step, i.e., the bio-processing and production of liquid feed or fertilizer. Using the hydrothermal technique, we studied the temporal change in internal temperature and pressure in a reactor on the elapsed heating time to check the equipment safety in terms of temperature and pressure. The gaseous and water-soluble liquid was also characterized to investigate the feasibility of retrieving valuable chemicals and emitting environmentally hazardous substances. From the changes in the internal temperature and pressure curve, the maximum temperature and pressure were 196 °C and 1.42 MPa for 30-min elapsed heating time, which was below the predefined temperature limits of 200 °C and pressure of 1.55 MPa. No such irregular behavior was observed in the temperature and pressure curve except that it was a little different for the foreign matter detergent, which also was within the limits. The qualitative and quantitative analysis of end products showed that the emitted malodorous substances and chemicals were further below the threshold levels for Japan. 相似文献
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Takeyasu M Iida T Tsujimoto T Yamasaki K Ogawa Y 《Journal of environmental radioactivity》2006,88(1):74-89
The concentrations and the concentration ratios of individual short-lived (222)Rn decay products ((214)Pb and (214)Bi) in rainwater were measured at Kumatori village (34.39 degrees N, 135.35 degrees E, approximately 70 m above sea level) in Osaka, Japan, by gamma-ray spectrometry using a low-background Ge detector. The dependence of the time variations of the concentrations and their ratios on rainfall rate was investigated. It was observed that the concentrations were negatively correlated with the rainfall rate in some rainfall events, and that there was no clear correlation in other rainfall events. The changes in the dependence of the concentration on the rainfall rate occurred after the passage of a cold front during a single rainfall event. The concentration ratios showed a weak negative correlation with the rainfall rate for most of the observed rainfall events. A scavenging model was designed in this study in order to explain the observation results. Based on the relationship between the concentrations of (214)Pb and (214)Bi in the rainwater and the rainfall rate for an individual rainfall event, the increase in the environmental gamma-ray dose rate from (214)Pb and (214)Bi deposited on the ground was calculated, and the calculated increase agreed well with that observed by the in situ measurement on flat ground. 相似文献
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For the evaluation of pedestrian protection, the European Enhanced Vehicle-Safety Committee Working Group 17 report is now commonly used. In the evaluation of head injuries, the report takes into account only the hood area of the vehicle. But recent pedestrian accident data has shown the injury source for head injury changing to the windshield and A-pillar from the hood. The head contact points are considered to fall on a parallel to the front shape of the vehicle along the lateral direction, but the rigidity of the outer side construction is different from the center area. The purpose of this study is to consider the reason for the change in injury source for recent vehicle models. The head contact points and contact conditions, speed and angle, are thought to be influenced not only by the vehicle's geometry, but also its construction (rigidity). In this study, vehicle-pedestrian impact simulations were calculated with a finite element model for several hitting positions, including the outer side areas. Full dummy sled tests were conducted to confirm the simulation results. These results show that, for impacts at the outer sides of the vehicle, the head contact points are more rearward than at the vehicle center. In addition, the speed and angle of the head contact were found to be influenced by the pedestrian height. 相似文献
19.
Kan-ichiro Matsumura Rover J. Hijmans Yann Chemin Christopher D. Elvidge Kenji Sugimoto Wenbin Wu Yang-won Lee Ryosuke Shibasaki 《Sustainability Science》2009,4(2):301-313
Rice plays a major role in the global supply and demand for sustainable food production. The constraints of maintaining sustainable
rice production are closely linked to the relationship between the distribution patterns of human activity on the planet and
economic growth. Global patterns of rice production can be mapped by using various criteria linked to domestic income, population
patterns, and associated satellite brightness data of rice-producing regions. Prosperous regions have more electric lighting,
and there are documented correlations between gross domestic product (GDP) and nighttime light. We chose to examine global
rice production patterns on a geographical basis. For the purposes of this study, each country is considered to be made up
of regions, and rice production is discussed in terms of regional distribution. A region is delineated by its administrative
boundaries; the number of regions where rice is produced is about 13,839. We used gridded spatial population distribution
data overlain by nocturnal light imagery derived from satellite imagery. The resultant relationship revealed a correlation
between regional income (nominal values of GDP were used) and rice production in the world. The following criteria were used
to examine the supply and demand structure of rice. Global rice consumption = “caloric rice consumption per capita per day”
multiplied by “regional population values”. Regional rice yields = “country-based production” divided by “harvested area”
(multiple harvests are taken into account). Regional rice production = “regional harvested areas” multiplied by “rice yield
values”. We compared regional rice consumption and production values according to these methods. Analysis of the data sets
generated a map of rice supply and demand. Inter-regional shipping costs were not accounted for. This map can contribute to
the understanding of food security issues in rice-producing regions and to estimating potential population values in such
regions. 相似文献
20.
Biomagnification profiles of tributyltin (TBT) and triphenyltin (TPT) in Japanese coastal food webs elucidated by stable nitrogen isotope ratios 总被引:1,自引:0,他引:1
The measurement of organotins in the various biotas of coastal food webs with stable nitrogen isotope ratios (δ15N), which increase 3.4‰ per trophic level, can provide a biomagnification profile of organotins through food web. In this study, various biological samples were collected from three localities in Western Japan between 2002 and 2003 for analyses. Tributyltin (TBT) and triphenyltin (TPT) were still detected with a maximum of 99.5 and 8.7 ng wet weight g−1, respectively. Unlike TBT, significant biomagnification of TPT through the food web (expressed by δ15N) was found in all three localities. The log transformed octanol–water partition coefficient (log Kow) of TPT of 2.11–3.43 was overlapped by, but was slightly lower than, that of TBT of 3.70–4.70. Thus, this study demonstrates that although these chemicals have a log Kow lower than 5, at least TPT undergoes significant biomagnification through the food web. 相似文献