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Community Structure of Macrobenthos in the Subtidal Soft Bottom in Semi- enclosed Youngsan River Estuarine Bay, Southwest Coast of Korea (반폐쇄적인 영산강 하구역 조하대 연성저질의 저서동물 군집)

  • LIM Hyun-Sig;PARK Kyung-Yang
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.3
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    • pp.320-332
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    • 1999
  • Investigations were made on the community structure of macrobenthos in the subtidal soft bottom around semi-enclosed Youngsan River estuarine bay, southwest coast of Korea during the period from April 1995 to February 1996. Three macrobenthos samples were collected at 40 stations using a van Veen grab(0.1 m^2) during the study period. A total of 206 species of macrobenthos was identified. Their mean density and biomass (wet-weight, wwt) were $1,137 ind./m^2$ and $65.28 gwwt/m^2$, respectively. Of these, there were 74 species of polychaetes ($36\%$), 60 molluscs ($39\%$), 51 crustaceans ($25\%$) and 21 miscellaneous taxa. Molluscs were represented as a density- and biomass-dominant faunal group with a mean density of $601 ind./m^2$($53\%$ of the total benthic animals) and biomass of $25.37 gwwt/m^2$($39\%$ of total biomass): It was followed by polychaetes with $405 ind./m^2$($40\%$ of the total density). Total number of species and diversity were Bow in the inner estuarine bay containing high mud content and organic matter, whereas they were high in the outer stations containing low mud content and organic matter. Major dominant species were one biralve, Theora fragilis and three Polychaetes, Tharyx sp., Poeciloceatus johnonni and Lumbrineris lontifolia whose mean densities were $490ind./m^2$, $96ind./m^2$, $74ind./m^2$and $52 ind./m^2$, respectively. Cluster analysis indicated that the study area could be divided into four station groups: two innermost station groups, a central bay and an outer station group. The species diversity increased from the inner station group toward the outer groups. These results were discussed in terms of both the environmental factors and distribution of benthic community.

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fisheries Biology of Shrimps in the South Western Waters of Korea -1. Species Composition of Catches and Spawning Season of Acetes sp. for the Korean Shrimp Fishery- (우리나라 서해남부해역의 새우류 어획물에 대한 자원생물학적 연구 -1. 어획물조성과 젓새우류의 산란시기-)

  • Oh Chul Woong;Jeong In Ju
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.3
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    • pp.223-230
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    • 2002
  • Investigations were made on catch composition, sex ratio, relationships between carapace length, body weight and fecundity and spawning season of major target shrimps (Acetes chinensis, A. japonicus) in the shrimp fishing areas of south-western coastal waters, accounting for about $45\%$ of annual shrimp landings in Korea. Catches were collected monthly in the fishing areas from March 2000 to February 2001, using single pocket-walled fishing gear, Total 59 species (shrimps 14, fishes 34, other crustaceans 8 and cephalopods 3 species) occurred. During the study period the bycatch-to-shrimp ratio of shrimp fishery was 2.42 in April 2000 and less than 1 for all months except for August 2000 and Febuary 2001. Compared with shrimp fishery of other areas and nations, these results indicate that effect of the fishing gear on catches of other species is minor, suggesting higher gear selectivity for shrimps. Of shrimps, there were two dominant species (A. chinensis, A. japonirus). Average sex ratio was 1.44 $\pm$ 0.42 for A. japonicus and 1,44 $\pm$ 0.43 for A. chinensis, which are dominant females in August. Average fecundity was 4,812 $\pm$ 1,511 for A. japonicus and 5,561 $\pm$ 1,900 for A. chinensis. In the two species mature females were found in the period from May to August. Similarly, the gonadosomatic index (GSI) was higher in July and August, with a peak in July, These results indicate that their main spawning season was summer.

Trace Element Analysis and Source Assessment of Household Dust in Daegu, Korea (대구지역 일반주택의 축적먼지 중 미량원소성분 분석과 오염원 평가)

  • Do, Hwa-Seok;Song, Hee-Bong;Jung, Yeoun-Wook;Yoon, Ho-Suk;Kwak, Jin-Hee;Han, Jeong-Uk;Kang, Hye-Jung;Phee, Young-Gyu
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.1
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    • pp.69-78
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    • 2010
  • In order to investigate the degree of household dust contamination, 48 samples of household dust (24 from urban area and 24 from rural area) in Daegu city were collected in vacuum cleaner during January to February 2009. Samples were sieved below 100 ${\mu}m$, and 14 elements (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, V, Zn) were analyzed using ICP after acid extraction. Results obtained from the source assessment of trace elements using enrichment factor showed that Ca, Fe, K, Mg, Mn, Na, and V were influenced by natural sources such as weathered rock and resuspended soil, while Cd, Cr, Cu, Ni, Pb and Zn were influenced by anthropogenic sources such as fuel combustion and waste incineration. Concentrations were remarkably higher in components from natural sources than in components from urban anthropogenic sources. Household dust in urban area was more affected by anthropogenic sources compared with that of rural area. Pollution index of heavy metals revealed that urban area was 1.8 times more contaminated with heavy metal components than rural area. The correlation analysis among trace elements indicated that components were correlated with natural sources-natural sources (Al-Mg, Al-Mn, Fe-Mn) and natural sources-anthropogenic sources (Al-V, Fe-Cr, V-Mn) in both urban area and rural area. Trace element components of rural area were more correlated than those of urban area. Houses that use oil for heating fuel had relatively higher contents of heavy metals rather than those using gas or electricity for heating fuel. Houses with children also had higher contents of heavy metals. In addition, the age of houses was found to influence the heavy metal levels in household dusts, with older houses (>10years) having higher concentrations than newer houses (<10years) and houses located near the major road (<10 m) were found to have relatively higher heavy metal levels in household dust.

Association between intakes of minerals (potassium, magnesium, and calcium) and diet quality and risk of cerebral atherosclerosis in ischemic stroke patients (뇌졸중 환자들의 무기질 (칼륨, 마그네슘, 칼슘) 섭취와 식사의 질 및 대뇌 죽상경화증과의 상관성 연구)

  • Son, Jihyun;Choe, Han-Saem;Hwang, Ji-Yun;Song, Tae-Jin;Chang, Yoonkyung;Kim, Yong-Jae;Kim, Yuri
    • Journal of Nutrition and Health
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    • v.48 no.2
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    • pp.167-179
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    • 2015
  • Purpose: This study was conducted to evaluate the association between intakes of potassium, magnesium, and calcium and diet quality in ischemic stroke patients. Methods: This study analyzed data from 285 subjects recruited from February 2011 to August 2014 in Seoul, Korea. Nutrition intakes were obtained from a semi-quantitative food frequency questionnaire composed of 111 food items. The subjects were divided into 4 groups by quartiles according to intakes of potassium, magnesium, and calcium. Index of Nutritional Quality (INQ), Mean Adequacy Ratio (MAR), and DQI-International (DQI-I) were analyzed for assessment of diet quality. Results: We found a positive association of intakes of these three minerals with MAR and DQI-I after adjustment for age, sex, education level, smoking, atrial fibrillation, and total energy intake. However, total moderation of DQI-I score in the Q4 group was significantly lower than that of the Q1 group. The age, sex, education level, and smoking, atrial fibrillation, and total energy intake-adjusted odds ratios of extensive cerebral atherosclerosis were inversely associated with intake of magnesium (Ptrend = 0.0204). However, this association did not exist with intakes of potassium and calcium. Conclusion: Potassium, magnesium, and calcium rich and high quality diet could be associated with decreased risk of ischemic stroke, in part, via effect on extensive cerebral atherosclerosis.

Optimization of Pre-treatment of Tropical Crop Oil by Sulfuric Acid and Bio-diesel Production (황산을 이용한 열대작물 오일의 전처리 반응 최적화 및 바이오디젤 생산)

  • Kim, Deog-Keun;Choi, Jong-Doo;Park, Ji-Yeon;Lee, Jin-Suk;Park, Seung-Bin;Park, Soon-Chul
    • Korean Chemical Engineering Research
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    • v.47 no.6
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    • pp.762-767
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    • 2009
  • In this study, the feasibility of using vegetable oil extracted from tropical crop seed as a biodiesel feedstock was investigated by producing biodiesel and analysing the quality parameters as a transport fuel. In order to produce biodiesel efficiently, two step reaction process(pre-treatment and transesterificaion) was required because the tropical crop oil have a high content of free fatty acids. To determine the suitable acid catalyst for the pre-esterification, three kinds of acid catalysts were tested and sulfuric acid was identified as the best catalyst. After constructing the experimental matrix based on RSM and analysing the statistical data, the optimal pre-treatment conditions were determined to be 26.7% of methanol and 0.982% of sulfuric acid. Trans-esterification experiments of the pre-esterified oil based on RSM were carried out, then discovered 1.24% of KOH catalyst and 22.76% of methanol as the optimal trans-esterification conditions. However, the quantity of KOH was higher than the previously established KOH concentration of our team. So, we carried out supplemental experiment to determine the quantity of catalyst and methanol. As a result, the optimal transesterification conditions were determined to be 0.8% of KOH and 16.13% of methanol. After trans-esterification of tropical crop oil, the produced biodiesel could meet the major quality standard specifications; 100.8% of FAME, 0.45 mgKOH/g of acid value, 0.00% of water, 0.04% of total glycerol, $4.041mm^2/s$ of kinematic viscosity(at $40^{\circ}C$).

A Research Survey on the Characteristics of Burglaries: Focused on How to Utilize Private Security (침입절도 특성에 관한 조사연구: 민간경비 활용방안을 중심으로)

  • Kim, Dae-Kwon
    • Korean Security Journal
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    • no.22
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    • pp.15-35
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    • 2010
  • A larceny means stealing others' properties, as one of crime types most closely connected with common people. Along with fraud, it is the mostly common property crime; in particular, the largest number of people are exposed to a burglary. This study aims to find the schemes to utilize private guards according to the characteristics of burglary. To do so, a questionnaire survey was conducted into an actual condition of official statistics of burglary and into the criminals of burglary, with a view to understanding the behavioral characteristics of burglary and suggesting defense mechanisms to prevent the crime. Burglary is not just a major crime to be dealt with by public guards like the police but also one to be handled increasingly more by private guards. It is why this study intends to identify how to utilize private guards in preventing the crime. Investigations were made into 208 burglars, who were inmates of 10 correctional institutions (prisons or detention houses) across the country. It is found that only about 24% of burglars committed the crime through rational choice, about 60.7% were feared of their arrest at the time of their crime, and a very high percentage (69.9%) of them were assured of their successful crime. Burglaries usually happened at night, mostly in a summer day when everybody goes away from home for vacation. Primarily, the crimes took place in a private house of urban residential quarters. What burglars considered mostly for target selection includes 'profitability,' followed by 'surveillance' and 'risk.' Most (42%) of them committed the crime for the first time ever. Generally, they were not inclined to commit the crime while under the influence of alcohol or drug, which might prevent them from making reasonable decisions. 73.9% of the criminals said that they committed the crime singly without any accomplices.

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The Bibliographical investigation of the mallow, hollyhock, darkpull, sunflower (아욱(葵菜), 접시꽃(蜀葵), 닥풀(黃蜀葵), 해바라기(向日葵)에 대한 문헌고찰)

  • Kim, Jong-dug;Koh, Byung-hee
    • Journal of Sasang Constitutional Medicine
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    • v.11 no.1
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    • pp.221-240
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    • 1999
  • 1. Purpose of study In the medical science of 'Sasang', a constitutional examination(diagnosis) and a medical treatment are important however a dietary cure is considered as very important at the medical prevention and treatment. But there has been a confusion due to the different view concerning the constitutional foods in between scholars. There it is necessary for us to bring up the theoretical basis of the 'Sasang' constitutional - dietary cure by means of the bibliographical study in relation to a historic, characteristics, efficiency of the major foods. A mellow as called "Baekchejiju" has been used as a source of adding food materials when we make a boiling soup, which is only in Korea but not other countries case. We also studied a hollyhock, a 'Darkpull', a sunflower together with a mellow, because these plants contains a similar characteristics and same chinese word of 'Gue' at their name. At this study we would like to bring up the basis correcting the evil of the misinterpretation to be translated 'Gue' into 'Sunflower', which would be helpful to the current academic circles studied very rarely for the introduction process of sunflower. 2. Method of study We did a comparative study based on not only 'Bonchoseo - original plants book' but also agricultural books, boos of the same kinds and private books. 3. Result of study 1) A mellow has been changed its inscribed name from 'Abushil' to 'A-uk', to 'A-ok', to 'A-uk'. And a winter mellow is called as 'Dol-a-uk' which means the thing is changed a year. 2) The heliotropism of mellow has been used as the symbol of the loyalty and the intelligence. Its meaning has been interpreted expansively engaging with the heliotropism of a hollyhock, a Darkpull, and a sunflower. 3) Once 'Darkpull' had been recognized as 'one day flower'. But after sunflower come, people have confused and misread 'Darkpull' by 'Sunflower'. 4) The first record of sunflower among the existing bibliographical documents is "Chung-jang-gam-chun-seo" (1795). And It is presumed thal the sunflower had introduced in Korea at the early to mid of the eighteen century. 5) The interpretation for mellow has been made s confusion by a several documentary and dictionary record, but should be corrected to be right.

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Co-authorship patterns and networks of Korean radiation oncologists

  • Choi, Jin-Hyun;Kang, Jin-Oh;Park, Seo-Hyun;Kim, Sang-Ki
    • Radiation Oncology Journal
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    • v.29 no.3
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    • pp.164-173
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    • 2011
  • Purpose: This research aimed to analyze the patterns of co-authorship network among the Korean radiation oncologists and to identify attributing factors for the formation of networks. Materials and Methods: A total of 1,447 articles including contents of ‘Radiation Oncology' and 'Therapeutic Radiology' were searched from the KoreaMed database. The co-authorship was assorted by the author's full name, affiliation and specialties. UCINET 6.0 was used to fi gure out the author's network centrality and the cluster analysis, and KeyPlayer 1.44 program was used to get a result of key player index. Sociogram was analyzed with the Netdraw 2.090. The statistical comparison was performed by a t-test and ANOVA using SPSS 16.0 with p-value < 0.05 as the significant value. Results: The number of articles written by a radiation oncologist as the first author was 1,025 out of 1,447. The pattern of coauthorship was classified into five groups. For articles of which the first author was a radiation oncologist, the number of singleauthor articles (type-A) was 81; single-institution articles (type-B) was 687; and multiple-author articles (type-C) was 257. For the articles which radiation oncologists participated in as a co-author, the number of single-institution articles (type-D) was 280 while multiple-institution articles (type-E) were 142. There were 8,895 authors from 1,366 co-authored articles, thus the average number of authors per article was 6.51. It was 5.73 for type-B, 6.44 for type-C, 7.90 for type-D, and 7.67 for type-E (p = 0.000) in the average number of authors per article. The number of authors for articles from the hospitals published more than 100 articles was 7.23 while form others was 5.94 (p = 0.005). Its number was 5.94 and 7.16 for the articles published before and after 2001 (p = 0.000). The articles written by a radiation oncologist as the first author had 5.92 authors while others for 7.82 (p = 0.025). Its number was 5.57 and 7.71 for the Journal of the Korean Society for Therapeutic Radiology and Oncology and others (p = 0.000), respectively. Among the analysis, a significant difference in the average number of author per article was indicated. The out-degree centrality of network among authors was 4.26% (2.03-7.09%) while in-degree centrality was 1.31% (0.53-2.84%). The three significant nodes were classified and listed as following: Choi, Eun Kyung for 1991-1995, Kim, Dae Young for 1998-2001, Park, Won and Lee, Sang Wook for 2003-2010. Choi, Eun Kyung and Kim, Dae Young appeared in two cases, and ranked as the highest degree in centrality. In the key player analysis, Choi, Eun Kyung and Lee, Sang Wook appeared in two cases, and ranked as the highest. From the cluster analysis, Sungkyunkwan University, Seoul National University and Yonsei University revealed as the three large clusters when Ulsan University, Chonnam National University, and Korea Institute of Radiological & Medical Science as the medium clusters. Conclusion: The Korean radiation oncologist's society shows a closed network with numerous relationships among the particular clusters, and the result indicates it is different from other institutions in the pattern of co-authorship formation of the major hospitals.

Relative Magma Formation Temperatures of the Phanerozoic Granitoids in South Korea Estimated by Zircon Saturated Temperature (저콘 포화온도로 추정한 남한 현생이언 화강암의 상대적인 마그마 생성온도)

  • Sangong Hee;Kwon Sung-Tack;Cho Deung-Ryong;Jwa Yong-Joo
    • The Journal of the Petrological Society of Korea
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    • v.14 no.2 s.40
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    • pp.83-92
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    • 2005
  • It has recently been proposed that granites can be divided into hot and cold ones by absence and presence of inherited zircon, respectively, which is closely related to zircon saturation temperature. The Phanerozoic granites in South Korea are divided into high- and low-Zr groups in a $SiO_2-Zr$ diagram, which appears to be related to their intrusive age. Most Triassic-Jurassic granites belong to low-Zr group, whereas most Cretaceous-Early Tertiary granites belong to the high-Zr group with the exception of geographically distinct Masan and Jinhae granites that belong low-Zr group. Calculated zircon saturation temperatures using major elements and Zr contents indicate that the Cretaceous-Early Tertiary granites $(608-834^{\circ}C,\;average\; 782\pm31^{\circ}C)$ except for the Masan and Jinhae granites $(average\;759\pm16^{\circ}C)$ show higher temperature than the Triassic-Jurassic granites $(642-824^{\circ}C,\;average\;756\pm31^{\circ}C)$. U-Pb zircon isotope data of the Triassic-Jurassic granites reported so far define discordia in a concordia diagram, which indicates presence of inherited zircon and agrees with their low zircon saturation temperatures. So the Triassic-Jurassic granites appear to belong to cold granite. On the other hand, presence or absence of inherited zircon has not been known for the Cretaceous-Early Tertiary granites with relatively high zircon saturation temperature, so that their classification into hot or cold granite awaits further study. Nevertheless, the Creatceous-Early Tertiary granites may have formed at higher temperature than the Triassic-Jurassic granites, since zircon saturation temperature reflects formation temperature of magma to a certain degree.

Fluid Inclusions Trapped in Xenoliths from the Lower Crust/upper Mantle Beneath Jeju Island (I): A Preliminary Study (제주도의 하부지각/상부맨틀 기원의 포획암에 포획된 유체포유물: 예비연구)

  • Yang, Kyounghee
    • The Journal of the Petrological Society of Korea
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    • v.13 no.1
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    • pp.34-45
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    • 2004
  • This paper describes the textural relations of mantle xenoliths and fluid inclusions in mantle-derived rocks found in alkaline basalts from Jeju Island which contain abundant ultramafic, felsic, and cumulate xenoliths. Most of the ultramafic xenoliths are spinel-lherzolites, composed of olivine, orthopyroxene, clinopyroxene and spinel. The felsic xenoliths considered as partially molten buchites consist of quartz and plagioclase with black veinlets, which are the product of ultrahigh-temperature metamorphism of lower crustal materials. The cumulate xenoliths, clinopyroxene-rich or clinopyroxene megacrysts, are also present. Textural examination of these xenoliths reveals that the xenoliths are typically coarse grained with metamorphic characteristics, testifying to a complex history of evolution of the lower crust/upper mantle source region. The ultramafic xenoliths contain protogranular, porphyroclastic and equigranular textures with annealing features, indicating the presence of shear regime in upper mantle of the Island. The preferential associations of spinel and olivine with large orthopyroxenes suggest a previous high temperature equilibrium in the high-Al field and the original rock-type was a Al-rich orthopyroxene-bearing peridotite without garnet. Three types of fluid inclusions trapped in mantle-derived xenoliths include CO$_2$-rich fluid (Type I), multiphase silicate melt (glass ${\pm}$ devitrified crystals ${\pm}$ one or more daughter crystals + one or more vapor bubbles) (Type II), and sulfide (melt) inclusions (Type III). C$_2$-rich inclusions are the most abundant volatile species in mantle xenoliths, supporting the presence of a separate CO$_2$-rich phase. These CO$_2$-rich inclusions are spatially associated with silicate and sulfide melts, suggesting immiscibility between them. Most multiphase silicate melt inclusions contain considerable amount of silicic glass. reflecting the formation of silicic melts in the lower crust/upper mantle. Combining fluid and melt inclusion data with conventional petrological and geochemical information will help to constrain the fluid regime, fluid-melt-mineral interaction processes in the mantle of the Korean Peninsula and pressure-temperature history of the host xenoliths in future studies.