Search for neutrino decay during the 1999 solar eclipse     

S. Cecchini  G. Giacomelli  D. Haşegan  G. Mandrioli  O. Mariş  L. Patrizii  A. Plaian  V. Popa  L. Ştefanov  V. Văleanu 《Astrophysics and Space Science》2000,273(1-4):35-41

The solar neutrino problem could arise from oscillation of one neutrinotype into a secondtype. Neutrinos would have a mass and there could be the possibility ofradiative neutrino decays. We discuss the search for neutrino decaysduring the 1999 solar eclipse: it involves the emitted visible photons,while neutrinos travel from the Moon to the Earth. The concept and themain characteristics of the NOTTE experiment are presented.  相似文献   

Effect of ultraviolet irradiation on the production and composition of fatty acids in plankton in a sub-Antarctic environment     

Sun-Yong Ha  Hyong-Min Joo  Sung-Ho Kang  In-Young Ahn  Kyung-Hoon Shin 《Journal of Oceanography》2014,70(1):1-10

We investigated the effects of ultraviolet-B (UV-B) radiation on the natural phytoplankton assemblage in Marine Cove on King George Island, Antarctica, in December 2005. The amount of newly synthesized phytoplankton polyunsaturated fatty acids (PUFAs) was lower with exposure to full irradiation (PAR+UV-A+UV-B) than without such exposure (exposed instead to PAR+UV-A radiation) in an in situ incubation under the light conditions in two different types of incubation bottles: quartz bottles transmitting all light wavelengths including UV-B and polycarbonate bottles with no UV-B transmission and 20 % reduced PAR compared to the quartz bottle. However, the amount of newly synthesized saturated fatty acids was greater with than without UV-B radiation. Thus, UV-B radiation may have a significant influence on fatty acid synthesis in phytoplankton. In particular, the production of eicosapentaenoic acid [20:5(n-3)] and docosahexaenoic acid [22:6(n-3)] was reduced during incubation under the natural solar radiation including UV-B. To understand the indirect influence of UV-B on herbivores (the secondary producer), we conducted feeding experiments with amphipods fed in situ on the natural phytoplankton assemblage. The amphipods fed on the phytoplankton with the low PUFA values also exhibited a low PUFA accumulation rate, which could negatively affect their growth, development, and reproduction. Consequently, the diminished rate of essential fatty acid synthesis [especially 20:5(n-3) and 22:6(n-3)] in primary producers caused by UV-B exposure could affect the structure and function of the Antarctic marine ecosystem.  相似文献   

ENSO regulation of MJO teleconnection   总被引：1，自引：0，他引：1  

Ja-Yeon Moon  Bin Wang  Kyung-Ja Ha 《Climate Dynamics》2011,37(5-6):1133-1149

The extratropical teleconnections associated with Madden?CJulian Oscillation (MJO) are shown to have an action center in the North Pacific where the pressure anomalies have opposite polarities between the Phase 3 (convective Indian Ocean) and Phase 7 (convective western Pacific) of the MJO. The teleconnection in the same phase of MJO may induce opposite anomalies over East Asia and North America between El Ni?o and La Ni?a years. During MJO Phase 3, a gigantic North Pacific anticyclonic anomaly occurs during La Ni?a, making coastal northeast Asia warmer/wetter than normal, but the west US colder/drier; whereas during El Ni?o the anticyclonic anomaly is confined to the central North Pacific, hence the northwest US experiences warmer than normal weather under influence of a downstream cyclonic anomaly. During Phase 7, an extratropical cyclonic anomaly forms over the northwest Pacific during La Ni?a due to convective enhancement over the Philippine Sea, causing bitter winter monsoon over Japan; whereas during El Ni?o, the corresponding cyclonic anomaly shifts to the northeast Pacific due to enhanced convection over the equatorial central Pacific, which causes warm and wet conditions along the west coast of US and Canada. Further, the presence of ENSO-induced seasonal anomalies can significantly modify MJO teleconnection, but the aforementioned MJO teleconnection can still be well identified. During Phase 3, the MJO teleconnection pattern over North Pacific will be counterbalanced (enhanced) by El Ni?o (La Ni?a)-induced seasonal mean anomalies. During Phase 7, on the other hand, the MJO teleconnection anomalies in the northeastern Pacific will be enhanced during El Ni?o but reduced during La Ni?a; thereby the impacts of MJO teleconnection on the North America is expected to be stronger during El Ni?o than during La Ni?a.  相似文献   

Deficiencies and possibilities for long-lead coupled climate prediction of the Western North Pacific-East Asian summer monsoon     

Sun-Seon Lee  June-Yi Lee  Kyung-Ja Ha  Bin Wang  Jae Kyung E. Schemm 《Climate Dynamics》2011,36(5-6):1173-1188

Long-lead prediction of waxing and waning of the Western North Pacific (WNP)-East Asian (EA) summer monsoon (WNP-EASM) precipitation is a major challenge in seasonal time-scale climate prediction. In this study, deficiencies and potential for predicting the WNP-EASM precipitation and circulation one or two seasons ahead were examined using retrospective forecast data for the 26-year period of 1981–2006 from two operational couple models which are the National Centers for Environmental Prediction (NCEP) Climate Forecast System (CFS) and the Bureau of Meteorology Research Center (BMRC) Predictive Ocean–Atmosphere Model for Australia (POAMA). While both coupled models have difficulty in predicting summer mean precipitation anomalies over the region of interest, even for a 0-month lead forecast, they are capable of predicting zonal wind anomalies at 850 hPa several months ahead and, consequently, satisfactorily predict summer monsoon circulation indices for the EA region (EASMI) and for the WNP region (WNPSMI). It should be noted that the two models’ multi-model ensemble (MME) reaches 0.40 of the correlation skill for the EASMI with a January initial condition and 0.75 for the WNPSMI with a February initial condition. Further analysis indicates that prediction reliability of the EASMI is related not only to the preceding El Niño and Southern Oscillation (ENSO) but also to simultaneous local SST variability. On other hand, better prediction of the WNPSMI is accompanied by a more realistic simulation of lead–lag relationship between the index and ENSO. It should also be noted that current coupled models have difficulty in capturing the interannual variability component of the WNP-EASM system which is not correlated with typical ENSO variability. To improve the long-lead seasonal prediction of the WNP-EASM precipitation, a statistical postprocessing was developed based on the multiple linear regression method. The method utilizes the MME prediction of the EASMI and WNPSMI as predictors. It is shown that the statistical postprocessing is able to improve forecast skill for the summer mean precipitation over most of the WNP-EASM region at all forecast leads. It is noteworthy that the MME prediction, after applying statistical postprocessing, shows the best anomaly pattern correlation skill for the EASM precipitation at a 4-month lead (February initial condition) and for the WNPSM precipitation at a 5-month lead (January initial condition), indicating its potential for improving long-lead prediction of the monsoon precipitation.  相似文献   

Analysis and simulation of mesoscale convective systems accompanying heavy rainfall: The goyang case   总被引：1，自引：0，他引：1  

Hyun-Young Choi  Ji-Hyun Ha  Dong-Kyou Lee  Ying-Hwa Kuo 《Asia-Pacific Journal of Atmospheric Sciences》2011,47(3):265-279

We investigated a torrential rainfall case with a daily rainfall amount of 379 mm and a maximum hourly rain rate of 77.5 mm that took place on 12 July 2006 at Goyang in the middlewestern part of the Korean Peninsula. The heavy rainfall was responsible for flash flooding and was highly localized. High-resolution Doppler radar data from 5 radar sites located over central Korea were analyzed. Numerical simulations using the Weather Research and Forecasting (WRF) model were also performed to complement the high-resolution observations and to further investigate the thermodynamic structure and development of the convective system. The grid nudging method using the Global Final (FNL) Analyses data was applied to the coarse model domain (30 km) in order to provide a more realistic and desirable initial and boundary conditions for the nested model domains (10 km, 3.3 km). The mesoscale convective system (MCS) which caused flash flooding was initiated by the strong low level jet (LLJ) at the frontal region of high equivalent potential temperature (θ_e) near the west coast over the Yellow Sea. The ascending of the warm and moist air was induced dynamically by the LLJ. The convective cells were triggered by small thermal perturbations and abruptly developed by the warm θ_e inflow. Within the MCS, several convective cells responsible for the rainfall peak at Goyang simultaneously developed with neighboring cells and interacted with each other. Moist absolutely unstable layers (MAULs) were seen at the lower troposphere with the very moist environment adding the instability for the development of the MCS.  相似文献   

Biomarker responses in pelagic and benthic fish over 1 year following the Hebei Spirit oil spill (Taean, Korea)   总被引：1，自引：0，他引：1  

Jung JH  Kim M  Yim UH  Ha SY  An JG  Won JH  Han GM  Kim NS  Addison RF  Shim WJ 《Marine pollution bulletin》2011,62(8):1859-1866

After the Hebei Spirit oil spill incident (7th December, 2007) in the west coast of Korea, contamination of biliary PAH metabolite and hepatic biomarkers in a pelagic and a benthic fish was monitored for 1 year. Concentrations of 16 PAHs and alkylated PAHs in fish muscle were highest (22.0 ng/g d.w. for 16 PAHs and 284 ng/g d.w. for alkylated PAHs) at 5 days after the spill and then decreased rapidly to background levels at 11 months after the spill. Fish from the oiled site had elevated biliary PAH metabolite concentrations immediately after the spill; these declined steadily in both species, but were still above reference site concentrations 2 months after the spill. Oiled-site fish showed hepatic CYP 1A induction whose trend closely followed those of biliary PAH metabolite concentrations, implying continuous exposure to PAHs. Brain acetylcholinesterase activity was not related to oil exposure.  相似文献   

Phytoremediation of heavy metal‐contaminated water and sediment by Eleocharis acicularis     

Masayuki Sakakibara  Yuko Ohmori  Nguyen Thi Hoang Ha  Sakae Sano  Koichiro Sera 《洁净——土壤、空气、水》2011,39(8):735-741

Phytoremediation is an environmental remediation technique that takes advantage of plant physiology and metabolism. The unique property of heavy metal hyperaccumulation by the macrophyte Eleocharis acicularis is of great significance in the phytoremediation of water and sediments contaminated by heavy metals at mine sites. In this study, a field cultivation experiment was performed to examine the applicability of E. acicularis to the remediation of water contaminated by heavy metals. The highest concentrations of heavy metals in the shoots of E. acicularis were 20 200 mg Cu/kg, 14 200 mg Zn/kg, 1740 mg As/kg, 894 mg Pb/kg, and 239 mg Cd/kg. The concentrations of Cu, Zn, As, Cd, and Pb in the shoots correlate with their concentrations in the soil in a log‐linear fashion. The bioconcentration factor for these elements decreases log‐linearly with increasing concentration in the soil. The results indicate the ability of E. acicularis to hyperaccumulate Cu, Zn, As, and Cd under natural conditions, making it a good candidate species for the phytoremediation of water contaminated by heavy metals.  相似文献   

The international developmental state: The Japanese intellectual property system in Vietnam     

Tim Reiffenstein  Ha Thanh Nguyen 《Geoforum》2011,42(4):462-472

This article explores the international implications of the developmental state model of Japanese capitalism. It does so by investigating the extension of Japanese intellectual property (IP) policy and practice in Vietnam. The escalating role of intellectual property within Japanese industrial policy is first framed according to Johnson’s developmental state thesis and extended in reference to the ‘flying geese’ model of regional development in East Asia. This latter approach anticipates Vietnam’s growing importance as a site for Japanese foreign direct investment and technology transfer. Interviews with key informants from both countries and analysis of policy documents provide evidence of the extra-territorial practices employed by Japanese companies, government agencies, and IP intermediaries in Vietnam. These accounts bring to light key developmental mechanisms, such as the packaging of IP internationalization within Japan’s official development assistance (ODA) and the overseas pro-bono work performed by IP intermediary associations in which the line between benevolence and self-interest is blurred. The paper concludes by interpreting these practices in accordance with the broader strategic imperatives of Japan in the region.  相似文献   

Estimation of high-resolution sediment concentration profiles in bottom boundary layer using pulse-coherent acoustic Doppler current profilers     

H.K. Ha  J.P.-Y. Maa  K. Park  Y.H. Kim 《Marine Geology》2011,279(1-4):199-209

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Distinguishing changes in the Hadley circulation edge     

Moon  Hyejin  Ha  Kyung-Ja 《Theoretical and Applied Climatology》2020,139(3):1007-1017

Theoretical and Applied Climatology - The studies on poleward expansion of the Hadley circulation have mainly concentrated on linear trends with global warming. There is no consensus on how the...  相似文献