• Title/Summary/Keyword: North pacific

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Reconstruction of Changes in Eolian Particle Deposition Across the Mid-Pleistocene Transition in the Central Part of the North Pacific (중기 플라이스토세 전이기 전후 북태평양 중앙 해역 퇴적물에 기록된 풍성 퇴적물 입자 퇴적 양상 변화 복원)

  • Lee, Sojung;Seo, Inah;Hyeong, Kiseong
    • Ocean and Polar Research
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    • v.41 no.4
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    • pp.275-288
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    • 2019
  • We investigated flux, grain size distribution, Nd-Sr isotope composition, mineral composition, and trace metal composition (REEs and Sc) of inorganic silicate fraction (ISF, mainly Asian dust with an unrestricted amount of volcanic materials) deposited during 600~1000 ka across the Mid-Pleistocene Transition at core NPGP 1401-2A (32°01'N, 178°59'E, 5205m) taken from the central part of the North Pacific. Our results reveal about a 2-fold increase in ISF flux after 800 ka, which is associated with an increase in La/Sc and a decrease in mean grain size. Asian dusts are finer than volcanic materials and La/Sc increases with the enhanced contribution of Asian dusts. Thus, increased flux after 800 ka can be explained by the increased contribution of Asian dusts relative to volcanic materials, likely due to an intensified Westerly Jet (WJ) and the drying of the Asian continent after the MPT. Mean grain size of ISF varies systematically in relation to glacial-interglacial cycles with a decrease during glacial stages, which is consistent with the previous results in the study area. Such a cyclical pattern is also attributed to the increase in the relative contribution of Asian dusts over volcanic components in glacial stages due to intensified WJ and drying of the Asian continent. Thus, it can be concluded that climate changes that had occurred across the MPT were similar to those of interglacial to glacial transitions at least in terms of the dust budget. Different from the Shatsky Rise, however, compositional changes associated with glacial-interglacial mean grain size fluctuations are not observed in Nd-Sr isotope ratios and trace element composition in our study of the Hess Rise. This may be attributed to the location of the study site far (> 4,000 km) from the volcanic sources. The volcanic component at the study site comprises less than 10% and varies within 3% over glacial-interglacial cycles. Such a small variation was not enough to imprint geochemical signals.

Marine Algae and Early Explorations in the Upper North Pacific and Bering Sea

  • wynne, Michael J.
    • ALGAE
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    • v.24 no.1
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    • pp.1-29
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    • 2009
  • A synthesis of early exploration and the discovery of marine algae in the upper North Pacific and Bering Sea is presented covering the period from the late 1730s to around 1900. Information is provided about these early efforts to gather natural objects, including seaweeds, and names of these algae are enumerated. The first collections of marine algae in this broad region were those made by steller and Kracheninnkov from the Kamchatka Peninsula,Russia,during the Second Kamchatkan Expedition (1735-1742) and were described by Gmelin (1768). The first known algal collections in Alaska were those made byMerck in his 1790-1791 visits to Unalaska Island during the Billings expedition (1785-1794). British-sponsored expeditions for commercial purposes and for exploration and dis-covery allowed surgeon-naturallist Archibald Menzies to garher seaweeds that Dawson Turner and others worked up back in Europe. Several of the Russian Expeditions during the first half of the 18'!' century had naturalists aboard. the first Russian circumnavigation of the globe (1803-1806), with the ships 'Nadeshda' and 'Neva,' under the com-mand of Capt. Adam von Krusenstern had naturalists Langsdorff, Tilesius, and Horner, all of whom collected sea-weeds. The naturalist Adelbert Chanmisso accompanied the Romanzof Expedition (1815-1818) on the Russian vessel 'Rurik' under the command of Otto von Kotzebue and made collections of algae in the Aleutians as well as in the Kurils and Kamchatka. The Lutke expedition of 1826-1829 consisted of thw ships. Feodor Lutke was in command of the 'Seniavin' with K.H. Mertens aboard as physician-naturalist, and the 'Moller' was under the command of staniukovich accompanied by the naturalist G. Kastalsky. The first American-sponsored scientific expedition (1838-1842) was that commanded by Charles Wilkes, and the algae that were collected were worked up by J.W. Bailey and W.H. Harvey. The Russian naturalist Ilya Voznesenskii spent the period 1839-1849 in Russian Americ (Alaska and northern California) energetically traveling and making numerous collections of natural objects as well as ethno-graphic artefact. His algae were described by F.j. Ruprecht back in St. petersbung. The Swedish scientific vessel, the'Vega' (1878-1880), was under the command of Nordenskiold. The naturalist F.R. Kjellman made algal collections from Port Clarence, Alaska, as well as from bering Island and St. Lawrence Island in the Bering sea. The Harriman Alaskan Expedition in the summer of 1899, with the ship 'George W. Elder,' was sponsored by railroad magnate E.H. Harriman of New York City and had several scientific personnel aborad, including the phycologist De Alton Saunders. Algae were collected in Alaska and Washington. During the same summer of 1899 a scientific expedition organized by the University of California and including W.L. Jepson, L.E. Hunt, A.A Lawson, and W.A. Setchell as participants also visited Alaska and made collections of alage from various locations.

A Study on the Fishing Efficiency of the Jigging Gear Neon Flying Squid , Ommastrephes Bartrami in the North Pacific (북태평양 빨강오징어 채낚기의 조획성능에 관한 연구)

  • 오희국
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.30 no.3
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    • pp.150-160
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    • 1994
  • Drift gillnet fishery for neon flying squid in the North pacific was one of the major pelagic fisheries of Korea until 1992, its annual catch was 79, 000M/T as average during 1988-1992, but moratoriumed since 1993 according to the decision of UN. Therefore, for the developing of the new fishing gear for the squid, the seven types of rip hook by automatic squid jigging machine were experimented by the korean research vessel Pusan 851 (G/T 1.126, 2.600 PS) in the North Pacific (38 $^{\circ}$30'-43 $^{\circ}$N, 152 $^{\circ}$E-178 $^{\circ}$W) from July 6. 1993 to August 31. 1993. The investigation on catch rate, dropout rate, and catch condition of the rip hooks related to the fishing lamp power for aggregating the squid were carried out during the period. The results obtained are as follows: The composition of catch by automatic squid jigging machine was 83.9% for neon flying squid. 15.5% for boreopacific gonate squid. 0.6% for boreal clubhook squid, and 0.01% for luminous flying squid. The catch rate of neon flying squid was 94.6% in 13.6-18.3$^{\circ}C$ of surface water temperature and 5.4% in others. The higher catch rate of neon flying squid was made in the range 13.6-18.3$^{\circ}C$ of temperature at the surface and about 1$0^{\circ}C$ of temperature at the 100m layer. The CPUE of neon flying squid in the 13.6-18.3$^{\circ}C$ of surface water temperature was ranged 0.8-11.8kg (8.7kg as average). The mantle length and body weight of neon flying squid caught in the experiment were ranged 18.3-51.3 cm, 140-3, 980g and mean mantle length and mean body weight were 29.4cm, 972g respectively. The catch rate of neon flying squid was the highest at dawn with a value of 25.0% of the total catch. The body weight of neon flying squid caught by the D type hooks was 1.7 times more than that of the A type hooks. The dropout rate of neon flying squid caught by the seven types hooks was 7.9-57.5% (19.0% as average), and dropout rate of the D type hooks was 7.9% with 2.7 times decrease than that of the A type hooks. The catch efficiency of small sized neon flying squid in case of using on-off switch method on fishing lamp in 15 minutes intervals was 2.6 times higher than that of the on-switch method with same fishing lamp power.

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A Study on the Extratropical Cyclones in the North Pacific Ocean during the Winter Season for Safe Navigation of Ships (선박의 안전항해를 위한 겨울철 북태평양의 온대저기압에 관한 연구)

  • Ko, Nan-Young;Seol, Dong-Il
    • Journal of Navigation and Port Research
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    • v.44 no.6
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    • pp.447-452
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    • 2020
  • Extratropical cyclone in winter season is very important in safe operation of ships because it is a major cause of marine accidents due to its strong power. In this study, we used meteorological data, to analyze extratropical cyclones occurring near the 1st Pacific polar front from December 2019 to February 2020. The analysis results are as follows. During those three months, we recorded 41 extratropical cyclones, 8 of which were remarkably developed. The central pressure of the strongest cyclone was 947hPa. The highest number of cyclones were generated in the East P acific Ocean around J apan (16), followed by the areas around Korea, the East China Sea, and the southern Sea of J apan. The cyclones followed five major tracks with a common northeast pattern. We thus concluded that the optimal route for a ship encountering an extratropical cyclone in the North P acific in winter would be south of the cyclone's center traveling eastbound and north of the center traveling westbound.

Prevalence of Tobacco Use Among Adolescents in North Kerala, India

  • Muttappallymyalil, Jayakumary;Divakaran, Binoo;Thomas, Teena;Sreedharan, Jayadevan;Haran, Jeesha C.;Thanzeel, Mohammed
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.11
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    • pp.5371-5374
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    • 2012
  • The present study was conducted to assess the prevalence and type of tobacco use among adolescents and also the reasons for the initiation of tobacco use amongst them. It was conducted in ten randomly selected schools in the Kannur district of Kerala state, India. A total of 3,000 school children participated. The study observed an overall prevalence of 5.5%. The prevalence observed among boys was 12% and none of the girls were tobacco users. Association between father's and friend's tobacco habits were observed.

Integrated Phytoplankton Data of the west Pacific Sector of the Southern Ocean: 149-148 $^{\circ}E$ transect

  • Lee Hak Young;Cho In Sook;Greene Richard M.;Kim Jong Won
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.2 no.1
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    • pp.21-28
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    • 1998
  • A total of 94 taxa were identified from the Southern Ocean, 140-148 $^{\circ}E$ and 40-53 $^{\circ}S$, as an early austral summer phytoplankton. They were 53 diatoms, 37 dinoflagellates, 2 silicoflagellates, 1 prymnesiophyte, and 1 coccolithophorid. Integrated cell numbers of nanoplankton dominated microphytoplankton from 8 stations, especially from Subantarctic zone, but integrated biomass was lower than microphytoplankton. Integrated cell numbers of diatoms dominated dinoflagellates, coccolithophorids, and prymnesiophyte, but integrated biomass of microphytoplankton were dependent to the biomass of dinoflagellates except north of the Subtropical convergence zone and south of the Antractic convergence zone. Phytoplankton community changed across the fronts and 3 different communities were observed. Fronts seem to influence on the phytoplankton community from the west Pacific Sector of the Southern Ocean.

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Differences in Incidence, Mortality and Survival of Breast Cancer by Regions and Countries in Asia and Contributing Factors

  • Kim, Yeonju;Yoo, Keun-Young;Goodman, Marc T
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.7
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    • pp.2857-2870
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    • 2015
  • Although the incidence of breast cancer in Asia remains lower than in North America, Western Europe, and Oceania, rates have been increasing rapidly during the past few decades, and Asian countries now account for 40% of breast cancer cases diagnosed worldwide. Breast cancer mortality has also increased among Asian women, in contrast to decreased mortality in Northern America, Western Europe, and Oceania. These increased rates are associated with higher prevalence of breast cancer risk factors (e.g., reduced parity, delayed childbirth, increased obesity) that have accompanied economic development throughout the region. However, Asian regions (western, south-central, south-eastern, and eastern) and countries differ in the types and magnitude of changes in breast cancer risk factors, and cannot be viewed as a single homogeneous group. The objective of this paper was to contrast the heterogeneous epidemiology of breast cancer by Asian regions and countries, and to suggest potential avenues for future research.

Tectonic and magmatic development of Bismarck Sea, Papua New Guinea

  • Lee, Sang-Muk
    • 한국지구물리탐사학회:학술대회논문집
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    • 2006.06a
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    • pp.209-210
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    • 2006
  • The Bismarck Sea represent a unique region in the equatorial western Pacific where one can explore the relationship between tectonic and magmatic processes associated with back-arc opening. The sea, located north of Papua New Guinea and just south of the equator, formed during the final stages of a long, complex geological development of the Melanesian Borderland. The development resulted from the Cenozoic convergence between the Australian and Pacific- Caroline Plates and the opening of back-arc basins. At present, the Bismarck Sea straddles two oppositely facing trenches, the inactive Manus trench and the active New Britain trench, and covers two basins, the New Guinea Basin (NGB) to the west and the Manus Basin (MB) to the east. The two basins are separated by the shallow Willaumez-Manus Rise (WMR), which trends roughly from WNW to ESE. The origin of these major structural units and their relationship with the presentday zone of major seismicity along the Bismarck Sea Seismic Lineation (BSSL) remains unclear and is the main focus of our study.

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Whither the TPP? Political Economy of Ratification and Effect on Trade Architecture in East Asia

  • Choi, Byung-il
    • East Asian Economic Review
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    • v.20 no.3
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    • pp.311-338
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    • 2016
  • In the race for establishing trading architecture consistent with new landscape of the global economy, the US is ahead of the game by concluding the Trans Pacific Partnership Agreement with 11 countries. To make it reality, the ratification is essential. In the battle for ratification in the US, declining globalism confronts rising protectionism. This paper models the ratification process as contest between globalism and protectionism, and analyzes the optimal timing for ratification. Based on this framework, various ratification scenarios are analyzed. The paper argues less likelihood for the lame-duck session passage and more likelihood for prolonged and protracted delay, due to changing political dynamics and declining intellectual support for globalism. Hence, the future of Trans Pacific Partnership Agreement may prove different, compared to the North American Free Trade Agreement and the Korea-US Free Trade Agreement, both of which were renegotiated and ratified eventually. Then, the US would lose the first move advantage. The paper also discusses strategic implications of delayed ratification on the evolution of trading architecture in East Asia.

Asian Cancer Registry Forum 2014-Regional Cooperation for Cancer Registration: Priorities and Challenges

  • Moore, Malcolm A.;Sangrajrang, Suleeporn;Bray, Freddie
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.5
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    • pp.1891-1894
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    • 2014
  • In February 6-7th, the Thai National Cancer Institute, the International Agency for Research on Cancer and its Mumbai Hub for Cancer Registration, together with the International Association of Cancer Registries and the APOCP/APJCP, jointly organized an Asian cancer registry forum to discuss regional cooperation for cancer registration. Held in the Grande Mercure Fortune Hotel, Bangkok, the meeting brought together leading scientists in cancer registration from South-East and North-East Asia as well as Australia, India and Iran and IARC itself, with coverage of various priorities and challenges of cancer registries regarding cancer control policy, operational parameters, assessment of survival and contributions to screening, for example. The current situation was highlighted and future directions and possible expansion of activities were discussed, with especial attention to the necessity for networks to help improve cancer registration across Asia and Africa.