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Fish Community Structure Analysis and Ecological Health Assessments in the Headwater Watershed of Nakdong River (낙동강 상류 수계의 어류 군집 구조 분석 및 생태건강도 평가)

  • Lee, Jae-Hoon;Hong, Young-Pyo;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.40 no.3
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    • pp.403-411
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    • 2007
  • The purpose of the study was to evaluate fish community, based on conventional at Shannon-Weaver diversity index (H'), and ecological health, based on the Index of Biological Integrity (IBI) using fish assemblage in the eight sites of Nakdong River during June${\sim}$August 1999. Total number of species sampled was 19 species, and two sensitive species of Zacco temminckii (51%) and Rhynchocypris oxycephalus (28%) dominated the fish community. Also, trophic guild analyses showed that insectivore was 87% of the total and omnivore was rare, indicating that the ecological health is well maintained in the system. The pattern of spatial variation in the diversity index(H') was very similar to patterns of the species number and individual number, whereas the pattern of H' was not matched with the tolerance and trophic guild data. The diversity index (H') showed highest (1.56) in Site 6 where the proportion of sensitive species and tolerant species was minimum and maximum, respectively, and where the insectivore and omnivore were minimum and maximum. In other words, the diversity index was not matched at all with the trophic and tolerant guilds, indicating that the conventional index did not reflect the ecological characteristics of fish community in the system. In the mean time, the ecological health (IBI) averaged 33.5 (n=8), indicating "good${\sim}$fair condition" and the IBI values matched with trophic and tolerance guilds. Maximum IBI occurred in Site 2 where the sensitive and msectivore species were nearly maximum, and the tolerant and omnivore species were almost minima, indicating that IBI values were closely associated with the ecological functions and health conditions. Overall data suggest that the conventional diversity index may not effective for a evaluation of fish community, and that in contrast the IBI approach may be a useful tool for diagnosis of stream community.

Comparison of Anticancer Activities of Berberis koreana Extracts Obtained by Different Extraction Processes (추출 공정별 매자나무 추출물의 항암활성 비교)

  • Ha, Ji-Hye;Kwon, Min-Cheol;Seo, Yong-Chang;Choi, Woon-Yong;Chung, Eul-Kwon;Chung, Ae-Ran;Kim, Jin-Chul;Ahn, Ju-Hee;Lee, Hyeon-Yong
    • Korean Journal of Food Science and Technology
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    • v.42 no.2
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    • pp.233-239
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    • 2010
  • This study was conducted to examine the anticancer activities of Berberis koreana extracts according to different extraction processes. The highest extraction yield obtained was 8.26% following extraction by ultrasonification at 60 kHz and $60^{\circ}C$ followed by high pressure at 500MPa. Generally, the extracts from the ultrasonification process showed relatively low cytotoxicities against the human normal cell line, HEK293 showing as low as 15%. This extract inhibited the growth of the digestive related organs cell lines, human stomach adenocarcimoma cell and human epithelial adenocarcinoma cell by up to 80% when administered at 1.0 mg/mL, and showed 2.5-3.5 of selectivity. It was also found that this extract induced the production of nitric oxide levels as high $37.87\;{\mu}M$ from macrophages. For the in vivo experiment using ICR mice, the total serum IgG levels of mice treated with B. koreana extracts from ultrasonification extraction were increased by up to 57 ng/mL. The survival time of this group was longer than that of the other group after the injection of Sarcoma-180 and the increment of their body weights was also greatly suppressed. In addition, the extract showed the highest tumor inhibition activities, leading to a reduction of 78.47%. These results indicate that the highest activities of B. koreana associated with this extraction process can be significantly improved.

Improvement of an Simultaneous Determination for Clenbuterol and Ractopamine in Livestock Products using LC-MS/MS (LC-MS/MS를 이용한 축산물 중 clenbuterol과 ractopamine의 동시 분석법 개선)

  • Cho, Yoon-Jae;Chae, Young-Sik;Kim, Jae-Young;Kim, Hyung-Soo;Kang, Ilhyun;Do, Jung-Ah;Oh, Jae-Ho;Kwon, Kisung;Chang, Moon-Ik
    • Korean Journal of Food Science and Technology
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    • v.45 no.1
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    • pp.25-33
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    • 2013
  • Clenbuterol and ractopamine, which are ${\beta}$-agonists, have been misused as a growth promoting agent in meat producing animals. Clenbuterol was banned for veterinary drug in Korea because of its problems regarding safety. Due to their adverse effects, such as cardiovascular and central nervous diseases on human health proper control and monitoring should be conducted. The existing analytical method of clenbuterol and ractopamine in the Food code was improved through our present study. The bovine muscle samples were subjected to enzymatic hydrolysis, extracted with ethyl acetate and defatted by hexane-methanol partitioning. A molecular imprinted polymer (MIP) solid phase extraction cartridge was used for clean-up and LC-MS/MS was operated in positive multiple reaction monitoring (MRM). Clenbuterol-$d_9$ and ractopamine-$d_3$ were used as an internal standard. The renewed method was validated according to the CODEX guideline. The limits of quantitation for clenbuterol and ractopamine were 0.2 and 0.5 ${\mu}g/kg$, respectively. The mean recoveries ranged in 104.2-113.5% for clenbuterol and in 107.6-118.1% for ractopamine. The improved method was able to save both time and expenses.

The Effect of Spiritual Nursing Intervention on Anxiety of the Hospice Patients (영적 간호중재가 호스피스 환자의 불안에 미치는 효과)

  • Yoon, Mae-Ok
    • Journal of Hospice and Palliative Care
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    • v.4 no.1
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    • pp.47-56
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    • 2001
  • Purpose : Surveying the effects on drop the anxiety of the hospice patients in spiritual nursing intervention with a quasi-experimental design using non-equivalent contrast group non-synchronized design to try in order to give the support which provide a holistic and individualizational nursing to comfort of hospice patients. Method : The results of survey were collected from 67 patients(67 subjects comprised 37 hospice patients of the experimental group and 30s of contrast) who were given hospice care from July to September of 2000 at the General Hospital in Cheon Ju city. The tool was used Spielberger's State Anxiety Scale, and the difference in the level of dropping anxiety among patient groups was analyzed with the mean, standard deviation, $x^2-test$. t-test and paired t-test. The spiritual nursing intervention was carried out through Hymn, Scripture, prayer, the therapeutic use of self over a period of three weeks. Results : 1) In general characters, men were a many more of the objects and the average age of the experimental and contrast group was 59.6, 55.9 respectively. The family of living together was $2{\sim}3$ members of most part. 2) There were not significant differences in the general, disease and therapeutic, religional characters between the experimental and contrast group. 3) The majority of the objects were cancer patients in disease and therapeutic characters(Experimental : 92%, Contrast : 95%). 4) After the spiritual nursing intervention state anxiety of the experimental group were remarkably lower than those of the contrast (t=-5.987, P=0.000). 5) Decreasing rate in the anxiety scores of before and post facto of the experimental group were remarkably lower than those of the contrast (t=6.237, P=0.000). Conclusion : The hospice patients who were offered spiritual nursing intervention became much lower than those who were not offered it in anxiety. Spiritual nursing intervention can be suited to field with one program of an effective that that relieved their anxieties. It is not only a very short time but has quite a little findings in part of spiritual nursing intervention. Therefore, further study in this field is necessary to concrete and substantial investigate in order to more and more increasing hospice patients in 21st century.

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Effects of Additives on Quality Attributes of Minced Ginger During Refrigerated Storage (첨가물이 냉장 중 생강 다대기의 품질특성에 미치는 영향)

  • Choi, Min-Seek;Kim, Dong-Ho;Lee, Kyung-Hae;Lee, Young-Chun
    • Korean Journal of Food Science and Technology
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    • v.34 no.6
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    • pp.1048-1056
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    • 2002
  • Quality of fresh ginger deteriorates rapidly during low temperature storage, and its storage life is short due to sprouting and microbial spoilage. The objectives of this research were to develop, using additives, a minced ginger product, which could maintain acceptable quality for over 30 days, and to investigate its quality changes during the cold storage. Storage stability of minced ginger product was investigated from the standpoint of the inhibition of brown discoloration, gas formation and liquid-solid separation. Fresh ginger was peeled and ground to produce minced ginger (control). Sodium bisulfite, L-cysteine, NaCl, sodium benzoate, modified starch, and/or xanthan gum were added to the control to minimize quality loss during storage, and to develop an optimum formula (A) of minced ginger. Samples were packed in Nylon/PE films, stored at $5^{\circ}C$, sampled at a 30-day interval, and subjected to quality evaluations. Changes in pH, surface color, gas formation, liquid-solid separation, contents of free amino acids, free sugars, organic acids, and fatty acids were determined. Gas formation was effectively inhibited in samples with sodium benzoate and/or NaCl. Samples with xanthan gum did not result in liquid-solid separation. L-Cysteine and sodium bisulfite were effective in controlling discoloration. pH decreased during storage in all samples, except sample A. Organic acid contents of all samples increased during storage, with lactic acid content showing the highest increase. Free amino acid content decreased with increasing storage time. Free sugar content of all samples decreased during storage. Sensory results showed sample A maintained acceptable quality until 90 days of storage. These results suggest that quality of minced ginger could be successfully maintained with the additions of selected additives for up to 90 days.

Laboratory Tests for Trichloroethylene (TCE) and Toluene Remediation in Soil Using Soil Vapor Extraction (토양증기추출(Soil Vapor Extraction)을 이용한 토양 내 Trichloroethylene (TCE)과 Toluene정화 실험)

  • 이민희;강현민
    • Economic and Environmental Geology
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    • v.35 no.3
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    • pp.221-227
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    • 2002
  • Column experiments were performed to evaluate the removal efficiency of soil vapor extraction (SVE) iota TCE (trichloroethylene) and toluene in soil. Homogeneous Ottawa sands and real soils collected from contaminated area were used to investigate the effect of soil properties and SVE operation conditions on the removal efficiency. In column teats with two different sizes of Ottawa sand, the maximum effluent TCE concentration in a coarse sand column was 442 mg/L and 337 mg/L in a fine sand column. However, after 20 liter gas flushing, the effluent concentrations were very similar and more than 90% of initial TCE mass were removed from the column. For two real contaminated soil columns, the maximum effluent concentration decreased 50% compared with that in the homogeneous Ottawa coarse sand column, but 99% of initial TCE mass were extracted from the column within 40 liter air flushing, suggesting that SVE is very available to remove volatile NAPLs in the contaminated soil. To investigate the effect of contaminant existing time on the removal efficiency, an Ottawa sand column was left stable for one week after TCE was injected and the gas extraction was applied into the column. Its effluent concentration trend was very similar to those for other Ottawa sand columns except that the residual TCE after the air flushing showed relatively high. Column tests with different water contents were performed and results showed high removal efficiency even in a high water content sand column. Toluene as one of BTEX compounds was used in an Ottawa sand column and a real soil column. Removal trends were similar to those in TCE contaminated columns and more than 98% of initial toluene mass were removed with SVE in both column.

Adaptive Lock Escalation in Database Management Systems (데이타베이스 관리 시스템에서의 적응형 로크 상승)

  • Chang, Ji-Woong;Lee, Young-Koo;Whang, Kyu-Young;Yang, Jae-Heon
    • Journal of KIISE:Databases
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    • v.28 no.4
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    • pp.742-757
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    • 2001
  • Since database management systems(DBMSS) have limited lock resources, transactions requesting locks beyond the limit mutt be aborted. In the worst carte, if such transactions are aborted repeatedly, the DBMS can become paralyzed, i.e., transaction execute but cannot commit. Lock escalation is considered a solution to this problem. However, existing lock escalation methods do not provide a complete solution. In this paper, we prognose a new lock escalation method, adaptive lock escalation, that selves most of the problems. First, we propose a general model for lock escalation and present the concept of the unescalatable look, which is the major cause making the transactions to abort. Second, we propose the notions of semi lock escalation, lock blocking, and selective relief as the mechanisms to control the number of unescalatable locks. We then propose the adaptive lock escalation method using these notions. Adaptive lock escalation reduces needless aborts and guarantees that the DBMS is not paralyzed under excessive lock requests. It also allows graceful degradation of performance under those circumstances. Third, through extensive simulation, we show that adaptive lock escalation outperforms existing lock escalation methods. The results show that, compared to the existing methods, adaptive lock escalation reduces the number of aborts and the average response time, and increases the throughput to a great extent. Especially, it is shown that the number of concurrent transactions can be increased more than 16 ~256 fold. The contribution of this paper is significant in that it has formally analysed the role of lock escalation in lock resource management and identified the detailed underlying mechanisms. Existing lock escalation methods rely on users or system administrator to handle the problems of excessive lock requests. In contrast, adaptive lock escalation releases the users of this responsibility by providing graceful degradation and preventing system paralysis through automatic control of unescalatable locks Thus adaptive lock escalation can contribute to developing self-tuning: DBMSS that draw a lot of attention these days.

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Effects of the 26-weeks Obesity Management Program on Obesity Index, Self-esteem, Self-efficacy, and Body Image among Obese Elementary School Children (초등학교 비만아동을 위한 26주-비만관리프로그램이 비만지수와 자아존중감, 자기효능, 및 신체상에 미치는 효과에 미치는 효과)

  • Lee, Jin Hee;Oh, Sangeun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.9
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    • pp.83-93
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    • 2016
  • This study was conducted to develop a 26-week obesity management program and examine the effects of this program on obesity index (body mass index, fat mass percentage, and triglyceride) and psychological variables, self-esteem, dietary self-efficacy, physical activity self-efficacy, and body image among 46 4th-6th obese elementary school children with a BMI above $20kg/m^2$ using a nonequivalent control group quasi-experimental design (experimental group=23, control group=23). This program included a 12-week intensive course (12 times for group education on obesity, exercise, and nutrition, 36 times for practicing diet and physical exercise, and 5 times for psychological counseling) and a 14-week follow-up course (3 times for group education, 3 times for checking diet and physical exercise, and 1 time for psychological counseling. The collected data were analyzed by the Kolmogorov-Smirnov test, chi-squared test, Fisher's exact probability, t-test, and ANCOVA. There were above normal values in body mass index ($20kg/m^2$), fat mass percentage (15-20%), and triglyceride tolerance ($90mg/d{\ell}$) in experimental group and control group. The body mass index (F=94.869, p<.001), fat mass percentage (F=37.361, p<.001), and triglyceride tolerance (F=7.907, p= .007) were significantly lower, while self-esteem (F=19.661, p<.001), dietary self-efficacy (F=16.942, p<.001), physical activity self-efficacy (F=9.363, p= .004), and body image (F=9.782, p= .003) were significantly higher in the experimental group than the control group after 26 weeks. This study provides evidence that the 26-weeks obesity management program is an effective nursing intervention for managing obesity and psychological variables of obese elementary school children.

Reliability of a Cobalt Silicide on Counter Electrodes for Dye Sensitized Solar Cells (코발트실리사이드를 이용한 염료감응형 태양전지 상대전극의 신뢰성 평가)

  • Kim, Kwangbae;Park, Taeyeul;Song, Ohsung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.4
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    • pp.1-7
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    • 2017
  • Cobalt silicide was used as a counter electrode in order to confirm its reliability in dye-sensitized solar cell (DSSC) devices. 100 nm-Co/300 nm-Si/quartz was formed by an evaporator and cobalt silicide was formed by vacuum heat treatment at $700^{\circ}C$ for 60 min to form approximately 350 nm-CoSi. This process was followed by etching in $80^{\circ}C$-30% $H_2SO_4$ to remove the cobalt residue on the cobalt silicide surface. Also, for the comparison against Pt, we prepared a 100 nm-Pt/glass counter electrode. Cobalt silicide was used for the counter electrode in order to confirm its reliability in DSSC devices and maintained for 0, 168, 336, 504, 672, and 840 hours at $80^{\circ}C$. The photovoltaic properties of the DSSCs employing cobalt silicide were confirmed by using a simulator and potentiostat. Cyclic-voltammetry, field emission scanning electron microscopy, focused ion beam scanning electron microscopy, and energy dispersive spectrometry analyses were used to confirm the catalytic activity, microstructure, and composition, respectively. The energy conversion efficiency (ECE) as a function of time and ECE of the DSSC with Pt and CoSi counter electrodes were maintained for 504 hours. However, after 672 hours, the ECEs decreased to a half of their initial values. The results of the catalytic activity analysis showed that the catalytic activities of the Pt and CoSi counter electrodes decreased to 64% and 57% of their initial values, respectively(after 840 hours). The microstructure analysis showed that the CoSi layer improved the durability in the electrolyte, but because the stress concentrates on the contact surface between the lower quartz substrate and the CoSi layer, cracks are formed locally and flaking occurs. Thus, deterioration occurs due to the residual stress built up during the silicidation of the CoSi counter electrode, so it is necessary to take measures against these residual stresses, in order to ensure the reliability of the electrode.

MICROLEAKAGE OF THE EXPERIMENTAL COMPOSITE RESIN WITH THREE COMPONENT PHOTOINITIATOR SYSTEMS (3종 광중합개시제를 함유한 실험용 복합레진의 미세누출도)

  • Kim, Ji-Hoon;Shin, Dong-Hoon
    • Restorative Dentistry and Endodontics
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    • v.34 no.4
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    • pp.333-339
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    • 2009
  • This study was done to determine if there is any difference in microleakage between experimental composite resins, in which various proportions of three component photoinitiators (Camphoroquinone, OPPI, Amine) were included. Four kinds of experimental composite resin were made by mixing 3.2% silanated barium glass (78 wt.%, average size; 1 ${\mu}m$) with each monomer system including variously proportioned photoinitiator systems used for photoinitiating BisGMA/BisEMA/TEGDMA monomer blend (37.5:37.5:25 wt.%). The weight percentage of each component were as follows (in sequence Camphoroquinone, OPPI, Amine): Group A - 0.5%, 0%, 1% / Group B - 2%, 0.2%, 2% / Group C - 0.2%, 1%, 0.2% / Group D - 1%, 1%, 2%. Each composite resin was used as a filling material for round class V cavities (diameter: 2/3 of mesiodistal width; depth: 1.5 mm) made on extracted human premolars and they were polymerized using curing light unit (XL 2500, 3M ESPE) for 40 s with an intensity of 600 mW/$cm^2$. Teeth were thermocycled fivehundred times between $50^{\circ}C$and $550^{\circ}C$for 30s at each temperature. Electrical conductivity (${\mu}A$) was recorded two times (just after thermocycling and after three-month storage in saline solution) by electrochemical method. Microleakage scores of each group according to evaluation time were as follows [Group: at first record / at second record; unit (${\mu}A$)]: A: 3.80 (0.69) / 13.22 (4.48), B: 3.42 (1.33) / 18.84 (5.53), C: 4.18 (2.55) / 28.08 (7.75), D: 4.12 (1.86) / 7.41 (3.41). Just after thermocycling, there was no difference in microleakage between groups, however, group C showed the largest score after three-month storage. Although there seems to be no difference in microleakage between groups just after thermocycling, composite resin with highly concentrated initiation system or classical design (Camphoroquinone and Amine system) would be more desirable for minimizing microleakage after three-month storage.