• Title/Summary/Keyword: the northeastern Pacific

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Longitudinal Distribution of Zooplankton at 10.5°N in the Northeastern Pacific (북동태평양 북위 10.5°에서 동물플랑크톤의 경도별 분포 특성)

  • Kang, Jung-Hoon;Cho, Kyu-Hee;Son, Ju-Won;Kim, Woong-Seo
    • Ocean and Polar Research
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    • v.29 no.4
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    • pp.283-295
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    • 2007
  • We investigated the longitudinal variations in zooplankton abundances and their related physicochemical properties at nine stations located between $136^{\circ}W$ and $128^{\circ}W$ at $10.5^{\circ}N$ in the northeastern Pacific in summer 2004. Temperature, salinity, inorganic nutrients, chlorophyll-a (hereafter chl-a) and zooplankton ($>200\;{\mu}m$) were sampled within the depth from the surface to 200 m depth at $1^{\circ}$ longitude intervals. Zooplankton($>200\;{\mu}m$) samples were vertically collected at two depth intervals from surface to 200 m, consisting of surface mixed and lower layers (thermocline$\sim$200 m). Longitudinal distributional pattern of hydrological parameters (especially salinity) was physically influenced by the intensity of westward geostrophic current passage relating to the NEC (North Equatorial Current). Data from the longitudinal survey showed clear zonal distributions in the hydrological parameters(temperature, salinity and nutrients). However, spatial patterns of the chl-a concentrations and zooplankton abundances were mostly independent of the zonal distributions of hydrological parameters. The two peaks of zooplankton abundance in the surface mixed layer were characterized by different controlling factors such as bottom-up control from nutrients to zooplankton ($129^{\circ}W$) and accumulation by increment of friction force and taxonomic interrelationship ($133^{\circ}$ and $134^{\circ}W$). Divergence-related upwelling caused introduction of nutrients into surface waters leading to the increment of chl-a concentration and zooplankton abundances ($129^{\circ}W$). Increased friction force in relation to reduced flow rates of geostrophic currents caused accumulation of zooplankton drifting from eastern stations of study area($133^{\circ}$ and $134^{\circ}W$). Besides, high correlation between immature copepods and carnivorous groups such as chaetognaths and cyclopoids also possibly contributed to the enhanced total abundance of zooplankton in the surface mixed layer (p<0.05). Zooplankton community was divided into three groups (A, B, C) which consecutively included the eastern peak of zooplankton($129^{\circ}W$), the western peak($133^{\circ}$ and $134^{\circ}W$) and high nutrient but low chl-a concentration and zooplankton abundance ($136^{\circ}W$). Moreover, Group B corresponded to the westward movement of low saline waters(<33.6 psu) from 128 to $132^{\circ}W$. In summary, longitudinal distributions of zooplankton community was characterized by three different controlling factors: bottom-up control ($129^{\circ}W$), accumulation by increased friction force and relationships among zooplankton groups ($133^{\circ}$ and $134^{\circ}W$), and mismatch between hydrological parameters and zooplankton in the high nutrient low chlorophyll area ($136^{\circ}W$) during the study period.

Lack of Participation of the GSTM1 Polymorphism in Cervical Cancer Development in Northeast Thailand

  • Natphopsuk, Sitakan;Settheetham-Ishida, Wannapa;Settheetham, Dariwan;Ishida, Takafumi
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.5
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    • pp.1935-1937
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    • 2015
  • The potential association between the GSTM1 deletion polymorphism and risk of cervical cancer was investigated in Northeastern Thailand. DNA was extracted from buffy coat specimens of 198 patients with squamous cell carcinoma of the cervix and 198 age-matched healthy controls. Genotyping of the GSTM1 was conducted by using two PCR methods, a short- and a long-PCR. Distribution of the GSTM1 genotypes in between the cases and the controls was not significantly different (p>0.5 by ${\chi}^2$ test). The results suggest that the GSTM1 deletion polymorphism is not a risk factor for squamous cell carcinoma of the cervix in the northeast Thai women.

Latitudinal Differences in the Distribution of Mesozooplankton in the Northeastern Equatorial Pacific

  • Kang, Jung-Hoon;Kim, Woong-Seo;Son, Seung-Kyu
    • Ocean and Polar Research
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    • v.26 no.2
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    • pp.351-360
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    • 2004
  • To investigate latitudinal variations in the zooplankton community along the meridian line ($5^{\circ}N-12^{\circ}N$, $131.5^{\circ}W$), we measured temperature, salinity, nitrate, chlorophyll-a and zooplankton at depths above 200 m from July $10^{th}$ to $25^{th}$, 2003. For comparative analysis, data of the physico-chemical properties and chl-a were matched to the two sampling depths (surface mixed layer and thermocline depth-200 m) of zooplankton. Latitudinal differences in the mesozooplankton distribution were mainly influenced by divergence formed at a boundary line formed by currents of opposing directions, consisting of North Equatorial Current (NEC) and North Equatorial Counter Current (NECC). High concentrations of chl-a south of $9^{\circ}N$, caused by equatorial upwelling related nutrients, is thought to be affected by the role of this divergence barrier, supported by relatively low concentrations in waters north of $9^{\circ}N$. The latitudinal differences of the chl-a were significantly associated with the major groups of zooplankton, namely calanoid and cyclopoid copepods, appendicularians, ostracods, chaetognaths, invertebrate larvae, and others. And temperature significantly affected the latitudinal variation of radiolarians, siphonophores, salps and immature copepods. The latitudinal differences in the two factors, temperature and chl-a, which explained 71.0% of the total zooplankton variation, were characterized by the equatorial upwelling as well as the divergence at $9^{\circ}N$. The physical characteristics also affected the community structure and abundance of zooplankton as well as average ratios of cyclopoid versus calanoid copepods. The abundance of dominant copepods, which were consistent with chl-a, were often associated with the carnivorous zooplankton chaetognaths, implying the relative importance of bottom-up regulation from physical properties to predatory zooplankton during the study period. These results suggested that latitudinal distribution of zooplankton is primarily controlled by current-related divergences, while biological processes are of secondary importance in the northeastern Equatorial Pacific during the study period in question.

The faunal composition of meiobenthic community in the deep-sea sediment, northeastern Pacific Ocean (북동 태평양 심해저퇴적물에 서식하는 중형저서생물의 군집조성)

  • Kim, Dong-Sung
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.2 no.1
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    • pp.42-47
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    • 1997
  • This study was carried out to investigate the faunal composition and distribution pattern of meiobenthic community in the deep sea sediments of northeastern Pacific Ocean. Faunal samples were collected at 10 stations using a multiple corer and a spade type box corer during May 1996. A total of 18 meiofaunal groups were found, and Sarcomastigophora was the most dominant group which accounted for 35.8% of total meiofaunal abundance. Nematoda (30.8%), Nauplius larvae of Crustacea (11.9%), Ciliophora (6.8%) and Harpacticoida (3.0%) which were also important components of the meiofaunal community. All of these five faunal groups comprised more than 90% of total meiofauna. The highest density of 195 ind./10 $cm^2$ was found at St. 4 (4960 m water depth), but the lowest one, 85 ind./10 $cm^2$ at St. 1 (4969 m water depth). The overall mean density of meiofauna was estimated as $1.34{\times}10^5\;ind./m^2$. The abundance of meiofauna showed a slow decreasing trend along the water depth. The highest density was observed in the upper 1 cm and density decreased drastically with increasing depth from the surface.

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Macrozoobenthic community in the deep sea soft-bottom of the KODOS 96-1 area, northeastern Pacific Ocean (북동태평양 KODOS 96-1 해역의 심해퇴적물에 분포하는 대형저서동물군집)

  • 최진우
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.1 no.2
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    • pp.73-79
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    • 1996
  • This study was conducted to investigate the faunal composition and distribution patterns of macrobenthic community in the deep sea sediments of the KODOS area, the northeastern Pacific Ocean during May 1996. Benthic animals were collected at 25 stations using a spade type box corer. Sediments were sieved through -.3 mm mesh screen. A total of 17 faunal groups in 9 phyla and 363 specimens were identified. Nematoda was the most abundant faunal group which accounted for 30.0% of total abundance. Other dominant faunal groups were foraminiferans (25.1%), harpacticoids (10.2%), xenophyophores (5.2%), and polychaetes (4.7%), Polychaeta was a typically dominant component of macrobenthic community in the study area except traditionally recognized meiofauna taxa. Mean occurrence number of faunal taxa was ca. 6 per 0.01 m$\^$2/, and mean density was estimated as 1,288 indiv./m$\^$2/. The abundance of whole fauna and that of each faunal group was highest at the surface layer of sediment, and decreased monotonously along the sediment depth; 98% of faunal abundance was found within 10 cm depth layer.

Reinfection by Opisthorchis Viverrini after Treatment with Praziquantel

  • Saengsawang, Phubet;Promthet, Supannee;Bradshaw, Peter
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.2
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    • pp.857-862
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    • 2016
  • Background: The prevalence of infection by the liver fluke, Opisthorchis viverrini (O. viverrini), has remained high in Northeast Thailand where it is a major risk factor for the eventual development of cholangiocarcinoma (CCA). The infection is acquired by the consumption of dishes containing unsafely prepared freshwater fish, a dietary tradition which has proved resistant to change. Since many people are aware that dosing with praziquantel (PZQ) is a successful treatment for an episode of the infection, there is a risk that, to avoid the long term consequences, they will engage in a cycle of infection, dosing and reinfection. Objectives: There is a dearth of studies of reinfection by O. viverrini, and the aims of this study were to assess re-infection rates in a typical province of Northeastern Thailand where O. viverrini infection is likely and to investigate factors associated with reinfection. Materials and Methods: A total of infected 607 villagers were treated with PZQ, and those found to be no longer infected were followed up at six-monthly intervals over 12 months. Results: At the end of this period data on 457 subjects were available for analysis using descriptive statistics and logistic regression, and 50 were found to have become reinfected, giving a cumulative reinfection rate of 10.9%. The results of a multiple logistic regression analysis showed that the only factor found to be associated with reinfection was past use of PZQ. Conclusions: Recommendations are made for future larger scale and better designed reinfection studies in the light of limitations of the current study. Further efforts are needed to discourage people from eating fish dishes likely to contain viable metacariae.

Spatial Analysis of Common Gastrointestinal Tract Cancers in Counties of Iran

  • Soleimani, Ali;Hassanzadeh, Jafar;Motlagh, Ali Ghanbari;Tabatabaee, Hamidreza;Partovipour, Elham;Keshavarzi, Sareh;Hossein, Mohammad
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.9
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    • pp.4025-4029
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    • 2015
  • Background: Gastrointestinal tract cancers are among the most common cancers in Iran and comprise approximately 38% of all the reported cases of cancer. This study aimed to describe the epidemiology and to investigate spatial clustering of common cancers of the gastrointestinal tract across the counties of Iran using full Bayesian smoothing and Moran I Index statistics. Materials and Methods: The data of the national registry cancer were used in this study. Besides, indirect standardized rates were calculated for 371 counties of Iranand smoothed using Winbug 1.4 software with a full Bayesian method. Global Moran I and local Moran I were also used to investigate clustering. Results: According to the results, 75,644 new cases of cancer were nationally registered in Iran among which 18,019 cases (23.8%) were esophagus, gastric, colorectal, and liver cancers. The results of Global Moran's I test were 0.60 (P=0.001), 0.47 (P=0.001), 0.29 (P=0.001), and 0.40 (P=0.001) for esophagus, gastric, colorectal, and liver cancers, respectively. This shows clustering of the four studied cancers in Iran at the national level. Conclusions: High level clustering of the cases was seen in northern, northwestern, western, and northeastern areas for esophagus, gastric, and colorectal cancers. Considering liver cancer, high clustering was observed in some counties in central, northeastern, and southern areas.

Survival of Cholangiocarcinoma Patients in Northeastern Thailand after Supportive Treatment

  • Thunyaharn, Nut;Promthet, Supannee;Wiangnon, Surapon;Suwanrungruang, Krittika;Kamsa-ard, Supot
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.11
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    • pp.7029-7032
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    • 2013
  • Background: Cholangiocarcinoma (CCA) is a very common cancer in Northeastern Thailand. Most CCA patients see a physician at a late stage when curative surgery is not possible. After diagnosis, they generally are treated by partial surgery/percutaneous drainage, chemotherapy and supportive treatment. Objective: This study aimed to assess the survival rates of CCA patients after supportive treatment. Methods: A retrospective cohort design was applied in this study. Data for 746 CCA patients were extracted from the hospital-based cancer registry of Srinagarind Hospital, Khon Kaen University. The patients were diagnosed (at least by ultrasonography) between 1 January, 2009 and 31 December, 2009 and then followed up for current status until 30 June, 2011. The cumulative survival rate was calculated by the Kaplan-Meier method, and independent prognostic factors were investigated using Cox regression. Results: The total follow-up time was 5,878 person-months, and the total number of deaths was 637. The mortality rate was therefore 10.8 per 100 person-year (95%CI : 10.1-11.7). The cumulative 3, 6, 9, 12 and 24 month survival rates were 59%, 39%, 31%, 24% and 14%, respectively. The median survival time after supportive treatment was 4 months. After adjusting for gender, age, stage, distant metastasis, histological grading and treatment, stage was a significant predictor of survival of CCA patients. Those in stage III and stage IV had a 6.78 fold higher mortality than the stage I and stage II cases (95% CI : 1.6-28.7). Conclusion: It is very important to encourage patients to see health personnel at an early stage.

Origin of Manganese Nodules and Their Distribution in the KODOS-89 Area, Northeastern Equatorial Pacific. (KODOS-89 지역 망간단괴의 성인과 분포)

  • 정회수;정갑식
    • 한국해양학회지
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    • v.25 no.4
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    • pp.189-204
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    • 1990
  • In the KODOS (Korea Deep Ocean Study)-89 area, western part of clarion-Clipperton fracture zones in the northeastern equatorial Pacific, magnate nodules and sediments were sampled during the 'Farnella' cruise in Oct., 1989. Bulk chemical and mineralogical analyses have been made on a suit of ferromanganese nodules and sediments to study the origin and distribution pattern of the nodules. The nodules are classified into three groups based on their origin: diagenetic nodules with high Mn/Fe ratio, Cu, Ni, Zn, Mg, todorokite contents and rough surface texture; hydrogenetic nodules with high Fe, Co, vernadite contents and smooth surface texture; and transitional nodules with intermediate characters between diagenetic and hydrogenetic nodules. Study area is divided into four zones according to the origin and abundance of nodules: far north area where nodules are hydrogenetic and intermediate in abundance; north area where nodules are diagenetic and low in abundance; south area where nodules are diagenetic and intermediate in abundance; seamount area where nodules are hydrogenetic and high in abundance. distribution pattern of manganese nodules in the KODOS-89 area seems to be controlled by latitudinal variation of productivity in water column and sea bottom morphology.

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Preliminary Study of the GSTM1 Null Polymorphism and History of Tobacco Smoking among Oral Cancer Patients in Northeastern Thailand

  • Natphopsuk, Sitakan;Settheetham-Ishida, Wannapa;Phuthong, Sophida;Ishida, Takafumi
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.2
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    • pp.739-742
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    • 2016
  • Risks with GSTM1 genotypes and potential roles of smoking in the susceptibility to oral squamous cell carcinoma (OSCC) were studied in Northeastern Thailand. Study subjects were 79 histologically-confirmed OSCC cases (31 men, 48 women) and 79 age- and sex-matched healthy controls ranging in age from 25 to 84 years. GSTM1 genotyping was achieved by two independent PCR assays. The GSTM1 null allele and the homozygous genotype did not increase risk of OSCC vs the wild type allele and the remaining genotypes. When the focus was on the smoking habit, male subjects who smoked ${\geq}10$ or ${\geq}35$ years were at significantly increased risk for OSCC with adjusted ORs of 4.88 [95%CI, 1.41-16.87, p=0.012] or 4.94 [95%CI, 1.62-15.12, p=0.005], respectively. A higher risk for OSCC was found for smoking amount; those who smoked >5 or >10 pack-years were at a higher risk with adjusted OR of 4.46 [95%CI; 1.45-13.74, p=0.009] or 3.89 [95%CI; 1.34-11.28, p=0.012], respectively. There are certain smoking patterns that give greater risks and thus both smoking duration and pack-years should be taken into consideration in tobacco related cancer prevention.