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The Regional Cooperation Agreement on Combating Piracy and Armed Robbery Against Ships in Asia (ReCAAP) Information Sharing Centre (ISC) is an international organisation that comprises 14 member countries in the region. Despite its many advantages, the ISC has some weaknesses, which when addressed could bring regional cooperation to a new level and which could make the ISC a model for other regions. 相似文献
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Review of recent findings on the water masses and circulation in the East Sea (Sea of Japan) 总被引:1,自引:0,他引:1
Kuh Kim Kyung-Il Chang Dong-Jin Kang Young Ho Kim Jae-Hak Lee 《Journal of Oceanography》2008,64(5):721-735
Recent findings on water masses, biogeochemical tracers, deep currents and basin-scale circulation in the East/Japan Sea,
and numerical modeling of its circulation are reviewed. Warming continues up to 2007 despite an episode of bottom water formation
in the winter of 2000–2001. Water masses have definitely changed since the 1970s and further changes are expected due to the
continuation of warming. Accumulation of current data in deep waters of the East/Japan Sea reveals that the circulation in
the East/Japan Sea is primarily cyclonic with sub-basin scale cyclonic and anticyclonic cells in the Ulleung Basin (Tsushima
Basin). Our understanding of the circulation of intermediate water masses has been deepened through high-resolution numerical
studies, and the implementation of data assimilation has had initial success. However, the East/Japan Sea is unique in terms
of the fine vertical structures of physical and biogeochemical properties of cold water mass measured at the highest precision
and their rapid change with the global warming, so that full understanding of the structures and their change requires in-depth
process studies with continuous monitoring programs. 相似文献
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Wynn C. G. Ho 《Monthly notices of the Royal Astronomical Society》2007,380(1):71-77
RX J1856.5−3754 is one of the brightest, nearby isolated neutron stars (NSs), and considerable observational resources have been devoted to its study. In previous work, we found that our latest models of a magnetic, hydrogen atmosphere match well the entire spectrum, from X-rays to optical (with best-fitting NS radius R ≈ 14 km, gravitational redshift z g ∼ 0.2 , and magnetic field B ≈ 4 × 1012 G). A remaining puzzle is the non-detection of rotational modulation of the X-ray emission, despite extensive searches. The situation changed recently with XMM–Newton observations that uncovered 7-s pulsations at the level. By comparing the predictions of our model (which includes simple dipolar-like surface distributions of magnetic field and temperature) with the observed brightness variations, we are able to constrain the geometry of RX J1856.5−3754, with one angle <6° and the other angle , though the solutions are not definitive, given the observational and model uncertainties. These angles indicate a close alignment between the rotation and the magnetic axes or between the rotation axis and the observer. We discuss our results in the context of RX J1856.5−3754 being a normal radio pulsar and a candidate for observation by future X-ray polarization missions such as Constellation-X or XEUS . 相似文献
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Trumpet shell, Charonia sauliae, is an endangered and valuable species, but its artificial propagation protocol has not been successfully established. To estimate the possibility of cryopreservation for larvae of C. sauliae, which is a potential preparation for its artificial reproduction and further research, in this study a protocol for the cryopreservation of veliger larvae of trumpet shell was optimized. Through a two-step cryopreservation procedure, four kinds of cryoprotectants (ethylene glycol, 1, 2-propanediol,dimethyl sulfoxide and glycerol) were employed at three concentrations (1.0, 1.5 and 2.0 molL-1) respectively and survival rates of larvae were determined after a storage of 1h. The larvae frozen with these four cryoprotectants after 1h storage were cultured, and then survival rates were determined at 24, 72 and 120h after thawing. Dimethyl sulfoxide at a concentration of 1.5 molL-1 showed the best protective effect in all experiments (p<0.05). And survival rates of larvae frozen with dimethyl sulfoxide were determined after 1,7 and 15 d of storage. The survival rates of larvae frozen with 1.5 molL-1 dimethyl sulfoxide after 1h, 1d, 7 d and 15 d of storage were 80.77% ±7.51%, 80.34% ±11.28%, 83.10% ±9.14% and 77.23%±6.22% respectively. No significant differences in survival rates of larvae frozen with dimethyl sulfoxide were observed after various storage periods (p>0.05). 相似文献
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Tung-Yuan Ho Chen-Feng You Wen-Chen Chou Su-Cheng Pai Liang-Saw Wen David D. Sheu 《Marine Chemistry》2009,115(1-2):125-133
The concentrations of cadmium, phosphorus, and aluminum in size-fractionated phytoplankton, zooplankton, and sinking particles are determined using ICPMS to evaluate the roles of biotic and abiotic particles on the cycling and ratios of Cd and P in the water column. Plankton were collected with a filtration apparatus equipped with 10-, 60-, and 150-μm aperture plankton nets on two occasions (2002 and 2006), and sinking particles were sampled by moored sediment traps deployed at depths of 120, 600, and 3500 m from 2004 to 2005. In contrast to what our previous study revealed, i.e., that most of the other bioactive trace metals in plankton were strongly correlated with abiotic Al and adsorbed on phytoplankton [Ho, T.Y., Wen, L.S., You, C.F., Lee, D.C., 2007. The trace metal composition of size-fractionated plankton in the South China Sea: biotic versus abiotic sources. Limnol Oceanogr 52, 1776–88.], Cd/P ratios, ranging from 0.12 to 0.34 mmol/mol P, did not vary with Al and exhibited fairly consistent values among different sizes of plankton, showing that Cd was mostly incorporated on an intracellular basis. In terms of the sinking particles, fluxes in Cd and P as well as in Cd/P ratios were strongly influenced by both biotic and abiotic particles. Overall, the Cd/P ratios in the sinking particles ranged from 0.03 to 1.2 mmol/mol, with the highest value observed in traps at 120 m during the productive season. The lowest value was observed in deep water during high flux periods for lithogenic particles. At surface depth, flux and Cd/P ratios were elevated during the most productive season in the region. The elevated ratios in the traps at 120 m were most likely related to preferential uptake of Cd for the dominant species (coccolithophores) during the productive period. Relatively, Cd/P ratios sharply decreased with increasing Al flux in deep water and ratios were much lower than the expected Cd/P ratios obtained from the relative portion of lithogenic and biogenic particles, indicating that the adsorption of soluble P into lithogenic particles was significant in the deep water during high lithogenic particle flux periods. Using averaged annual fluxes and standing stock in the water column, the residence time of biogenic Cd and P are 0.10 and 0.20, 250 and 100, and 9100 and 5000 years respectively in the top 120 m, 600 m, and water column as a whole, also showing preferential removal for Cd in the euphotic zone but relatively higher removal rates for P in the deep water. Our study suggests that the shift in microalgal community structure along with input of lithogenic minerals are both potentially important factors in influencing Cd/P ratios in oceanic water on a geological time scale. 相似文献
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