• Ocean and Polar Research
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• v.27 no.1
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• pp.35-44
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• 2005

The bathymetric and gravity data were obtained in 2001 and 2003 during a survey of seamounts in the northwest of the Marshall Islands, western Pacific. The study areas are located in the Pigafetta Basin which is the oldest part of the Pacific plate and in the Ogasawara Fracture Zone which formed from the spreading ridge between the Izanagi and Pacific plates in the Jurassic. The densities of seamounts and the elastic thickness values of the lithosphere are calculated by using three-dimensional flexure modeling considering the constant sediment layer in the infinite plate model. Very low elastic thickness values (5km), relatively young seamounts, and old lithosphere in the east study area suggest the possibility of the rejuvenation of lithosphere by widespread volcanisms, whereas the elastic thickness values (15km), relatively old seamounts, and young lithosphere of the west study area are suitable for a simple cooling plate model of $300-600^{\circ}C$ isotherm. The gravity residuals of OSM6-1 and OSM6-2 suggest the possibility of different load density or elastic thickness. Relatively older OSM6-2 formed on the younger lithosphere with relatively thin elastic thickness, while younger OSM6-1 on the older lithosphere with relatively thick elastic thickness.

• Ocean and Polar Research
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• v.41 no.3
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• pp.121-133
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• 2019

Natural variability associated with a variety of large-scale climate modes causes regional differences in sea level rise (SLR), which is particularly remarkable in the Pacific Ocean. Because the superposition of the natural variability and the background anthropogenic trend in sea level can potentially threaten to inundate low-lying and heavily populated coastal regions, it is important to quantify sea level variability associated with internal climate variability and understand their interaction when projecting future SLR impacts. This study seeks to identify the dominant modes of sea level variability in the tropical Pacific and quantify how these modes contribute to regional sea level changes, particularly on the two strong El $Ni{\tilde{n}}o$ events that occurred in the winter of 1997/1998 and 2015/2016. To do so, an adaptive data analysis approach, Ensemble Empirical Mode Decomposition (EEMD), was undertaken with regard to two datasets of altimetry-based and in situ-based steric sea levels. Using this EEMD analysis, we identified distinct internal modes associated with El $Ni{\tilde{n}}o$-Southern Oscillation (ENSO) varying from 1.5 to 7 years and low-frequency variability with a period of ~12 years that were clearly distinct from the secular trend. The ENSO-scale frequencies strongly impact on an east-west dipole of sea levels across the tropical Pacific, while the low-frequency (i.e., decadal) mode is predominant in the North Pacific with a horseshoe shape connecting tropical and extratropical sea levels. Of particular interest is that the low-frequency mode resulted in different responses in regional SLR to ENSO events. The low-frequency mode contributed to a sharp increase (decrease) of sea level in the eastern (western) tropical Pacific in the 2015/2016 El $Ni{\tilde{n}}o$ but made a negative contribution to the sea level signals in the 1997/1998 El $Ni{\tilde{n}}o$. This indicates that the SLR signals of the ENSO can be amplified or depressed at times of transition in the low-frequency mode in the tropical Pacific.

• Maritime Security
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• v.6 no.1
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• pp.1-35
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• 2023

The purpose of this study is to present the direction of development of our navy's response strategy through analysis at the ends, ways, and means level of the Chinese navy's offensive strategy for the West Sea. As a result of the analysis, at the ends level, the Chinese Navy's offensive strategy for the West Sea strategy is being linked to a grand strategy to protect maritime rights and achieve maritime power between the U.S. and China competition, at the ways level, the Chinese Navy is expected to create a foundation for the international community to recognize the West Sea as China's inland sea through "routine entry" and "exercise authority", and in case of emergency, it will try to secure sea control in the West Sea in a short period of time by blocking Korea's maritime transportation route based on the overwhelming preemptive attack capability of aircraft carriers. At the means level, it is accelerating the construction of aircraft carrier warfare units and improving its ability to engage long-range missiles. As a direction of development of the Korean Navy's response strategy in response to this, first, Establishment and Development of National Maritime Security Strategy in conjunction with the Korean Indo-Pacific Strategy. Second, it proposes the development of the concept of effective security operations for the east sea area of the West Sea intermediate line, and third, the development of the concept of combat performance and capacity building to strengthen survival and lethality.

• Journal of East-West Nursing Research
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• v.14 no.2
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• pp.47-53
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• 2008

Purpose: Metabolic syndrome (also known as insulin resistance syndrome) represents a constellation of hypertriglyceridemia, hypertension, impaired glucose tolerance, and obesity. Presently, the influence of various factors on metabolic syndrome was assessed in patients of a university hospital comprehensive medical examination center. Methods: Age, sex, blood pressure, height, weight, triglyceride level, high-density lipoprotein cholesterol, and glucose levels were measured in 67 people (37 males and 30 females). These factors were correlated with tobacco use, alcohol consumption, and exercise habits. Metabolic syndrome and abdominal obesity were assessed according to NCEP-ATP III criteria and the Asia-Pacific guidelines (male obesity defined as a waist circumference exceeding 90 cm), respectively. Data was analyzed using t-test, 2-test, and logistic regression. Results: Respective percentages were: tobacco use (14.9% of the 67 people), no tobacco use (85.1%), alcohol consumption (62.7%), no alcohol consumption (37.3%), regular exercise (25.4%), no regular exercise (74.6%). Logistic regression analysis revealed a gender-related odds ratio of 2.3 for metabolic syndrome and no exercise. Conclusions: Weight reduction and physical exercise may decrease the prevalence of metabolic syndrome. Early identification of metabolic syndrome and risk factor modification is prudent in cases of obesity, diabetes, hyperlipidemia, and hypertension.

• Journal of Environmental Science International
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• v.18 no.10
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• pp.1089-1101
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• 2009

In this paper, changes in the intensity (e.g., central pressure and maximum sustained wind speed) of Tropical Cyclone (TC) in summer in the regions located at $30^{\circ}N$ in East Asia from 1988 to 1991 were found. The intensity of TC from 1991 to 2007 was much higher than that of TC from 1965 to 1988. The reason for this was that the frequency of TCs passing China from 1991 to 2007 was much lower than that of TCs from 1965-1988 because a northeasterly wind caused by high-pressure circulation in East Asia got severer along the East Asian coast. Instead, TCs moved from the eastern region of the Tropical West Pacific to Korea and Japan mainly after passing the East China Sea due to the low-pressure circulation strengthened in the subtropical waters of East Asia. In addition, low Vertical Wind Shear (VWS) was created along the mid-latitude regions of East Asia and the main path of TCs from 1991 to 2007. Most of the regions in the Northwestern Pacific showed higher Sea Surface Temperature (SST) from 1991 to 2007, and had a good environment where TCs were able to maintain a higher intensity on the mid-latitude. In particular, a low sensible heat flux occurred due to high snow depth in East Asia in the spring of 1991 to 2007. Accordingly, the lower layer of East Asia showed high-pressure circulation, and the sea surrounding East Asia showed low-pressure circulation. Thus, the typical west-high, east-low pattern of winter atmospheric pressure was shown. The possibility of snowfall in East Asia in spring to be used as a factor for predicting the summer intensity of TC in the mid-latitude regions of East Asia was insinuated. The characteristics of TC in a low-latitude region were the same in Korea. The latest intensity of TCs got higher, and the landing location of TCs gradually changed from the west coast to the south coast.

• Journal of Aquaculture
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• v.21 no.3
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• pp.184-189
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• 2008

Tryptic enzyme activities in the digestive glands (hepatopancreas) and digestive tracts of Pacific white shrimps Litopenaeus vannamei were assayed at three water temperature regimes. At $26^{\circ}C$, trypsin activity in the hepatopancreas was 200% higher than at $23^{\circ}C$ and 300% higher than at $20^{\circ}C$. The highest foregut trypsin activity levels showed no significant difference in the temperature regimes, but the time between peaks in foreguts and midguts shortened at higher temperature. In the midgut, the level of enzyme activity was highest at $26^{\circ}C$ regardless of the amount of ingested feed. The ratio of foregut and/or midgut dry weight to the body wet weight indicated feed movement through the digestive track directly and gave accurate account about the feeding mechanism. Maximum feed ingestion in the foregut was equivalent to 0.6% of the body weight (wet weight) at $23^{\circ}C$, 0.4% of the body weight at $20^{\circ}C$, and 0.5% of the body weight at $26^{\circ}C$. In view of the temperatures chosen for this study, although maximum ingestion was observed at $23^{\circ}C$, the shrimps showed highest enzyme activity, but lowest feed retention time at $26^{\circ}C$ and lowest enzyme activity, but highest retention time at $20^{\circ}C$.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2401-2405
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• 2016

Background: Both colorectal cancer (CRC) and diverticular disease (DD) are common in the affluent West, and their prevalence is also increasing in the rest of the world with economic development. Both diseases have common epidemiologic characteristics; increasing incidence, more common with advancing age and related to specific dietary changes. However, studies of associations between the two have generated mixed results with some showing positive correlations, whilst others have shown no or negative links. Most of these studies have been from the West with study populations that were predominantly Caucasians. Here the focus was on DD and colorectal neoplasms, including CRC, in Brunei. Materials and Methods: All patients who had undergone complete colonoscopy between 2011 and 2014 were identified and retrospectively reviewed. Patients under the age of 18 years old or had previous colonic surgeries (including previous CRC resection) were excluded. Results: The total number of colonoscopies included in the study was 2,766 (mean age $53.2{\pm}14.8$ years old, male 51.8%), of which DD, CRC and colonic polyps were detected in 17.3%, 4.7% and 28.2% respectively. The proportions of DD, polyps and CRC increased proportionally with age (<30 years, 30-49, 50-69 and ${\geq}70$). Overall, there was no association between the presence of DD and CRC (3.6% vs. 5.0%, p=0.179) but there was a significant association between CRC and left sided DD (p=0.034 by trend). There were also a significant association between presence of DD and polyps (36.1% vs. 28.2%, p=0.001), in particular with right-sided and pan-DD (p=0.001 for trend). Conclusions: Our study showed that the prevalence of DD, CRC and polyps increases with age. There were significant associations between presence of left-sided DD with CRC and right-sided or pan-DD with colonic polyps. This suggests shared risk factors. Further studies are required to assess links in other countries of the Asian Pacific region.

• Korean Journal of Clinical Laboratory Science
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• v.50 no.3
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• pp.245-252
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• 2018

We evaluated the possible clinical application of Non HDL-cholesterol and triglyceride to HDL-cholesterol ratio as a metabolic syndrome predictor for the elderly in Korea. 1,543 elderly persons aged 65 years or older who visited the health examination center of Gyeonggi Regional General Hospital from January 2015 to December 2017 and had a health checkup were enrolled in this study. Metabolic syndrome was diagnosed based on the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) standards. Abdominal obesity was assessed by the Asia-Pacific standards presented at the World Health Organization (WHO) West Pacific Region. Non-HDL-cholesterol was calculated as the difference between total cholesterol and HDL-cholesterol. The metabolic syndrome predictive power was higher for triglyceride to HDL-cholesterol ratio than for Non HDL-cholesterol. After correcting for related factors, triglyceride to HDL-cholesterol ratio was higher in the $4^{th}$ quartile, which had a higher risk of developing metabolic syndrome, than in the $1^{st}$ quartile. The optimal cutoff value for the triglyceride to HDL-cholesterol ratio that predicts the onset of metabolic syndrome was 2.8. triglyceride to HDL-cholesterol ratio can be a simple and practical indicator of the risk of metabolic syndrome.

• Journal of the Korean association of regional geographers
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• v.5 no.1
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• pp.151-162
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• 1999

This study is a comparative analysis of sea level and 500hPa surfaces between dry year and wet year, which are selected by variability of precipitation and standardized anomalies in Korea in early autumn. While the amount of precipitation of early autumn decreases, the variability of precipitation increases rapidly reflecting the strength and weakness of Kaul Changma front and the occurrences of the typhoonic precipitation. The regional distribution of the variability of precipitation shows west-high, east-low pattern in which the east coast and the southeastern coast shows low, but high in the southwestern coast. In the anomalies distribution of sea-level and 500hPa surfaces, during dry year, the northern part of Siberia and the core area of North Pacific high shows negative anomalies, on the contrary, there were positive anomalies in wet year at the same areas. In addition, at the 500hPa level, while the Korean peninsula was located at the west of deep trough with low zonal index in dry year, the peninsula was influenced by weak trough with high zonal index showing strong zonal flow in wet year. During dry year the height of 500hPa surface is low at the north of $40^{\circ}N$, but high in wet year. In consequences, this study identified that the occurrences of dry year and wet year were influenced by the seasonal variations of the strength and the weakness of North Pacific high and Siberian high.

• The Korean Journal of Malacology
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• v.32 no.4
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• pp.269-277
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• 2016

We examined the seasonal variation of the proximate, amino acid, fatty acid composition and glycogen contents of triploid Pacific oyster cultured in western coastal waters of Korea in 2015. The specimens were collected in February, May, August and November from off-bottom farming site. The lipid content was the highest in winter season (February, $2.10{\pm}0.06%$), the protein content was the highest in autumn season (November, $9.09{\pm}0.04%$) while the moisture and ash content was the highest in summer season (August, $86.00{\pm}0.12%$ and $2.67{\pm}0.03%$, respectively). The total amino acid contents was the highest in winter season (1,011.5 mg / 100 g), decreased gradually and was the lowest in summer season (486.7 mg / 100 g). The total amino acid composition was dominated by taurine, aspartic acid, glutamic acid, glycine and alanine. In the fatty acid composition, the two fatty acids, eicosapentaenoic acid and docosahexaenoic acid, which comprised that as much as 50% of the total fatty acid contents, were dominated during all season. The glycogen content was the highest in summer season ($1.26{\pm}0.03g$ / 100 g) although it was stable during the other season with the range of $0.69{\pm}0.04-0.86{\pm}0.01g$ / 100 g. Taken together, these results suggest that triploid pacific oysters have high commercial value not only in winter season but in summer season because they do not spawn and have high contents of glycogen comparing with those of diploid oyster in this period.