• 한국환경농학회지
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• 제32권2호
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• pp.108-116
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• 2013

BACKGROUND: Certain crop-based waste materials have been recognized as cost-effective and highly efficient adsorbents for removal and recovery of different kind of heavy metals from aqueous solutions. The ability is strongly attributed to the carboxyl functional group of some pectin substances such as galacturonic acid often found in fruit peels. The present manuscript was aimed at assessing the potential applicability of banana peel for metal removal from contaminated waters. METHODS AND RESULTS: As revealed by laboratory investigations, banana peel contains pectin (10-21%), lignin (6-12%), cellulose (7.6-9.6%), and hemicelluloses (6.4-9.4%). The pectin extraction is reported to have glucose, galactose, arabinose, rhamnose, xylose, and galactouroninc acid. Several studies conducted under different conditions proved that banana peel is capable of adsorbing 5.71, 2.55, 28.00, 6.88, 7.97, and 5.80 mg/g of $Cd^{2+}$, $Co^{2+}$, $Cu^{2+}$, $Ni^{2+}$, $Pb^{2+}$, and $Zn^{2+}$, respectively, from aqueous solutions. Adsorption capacity is, however, dependent upon several factors including solution pH, dose of adsorbent and metal concentration, contact time and shaking speed. CONCLUSION(S): Since the annual world production of banana exceeds 100 million tons, about 40 million tons of banana peel (40% of total weight of the fresh fruit) remains vastly unused. Exploring a sound technology with banana peel would therefore, not only address the much needed sustainable tool for cleaning contaminated waters, but of course bring an additional value to the banana industry worldwide.

• ALGAE
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• 제32권4호
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• pp.349-357
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• 2017

Korean mariculture Undaria pinnatifida was collected during the months of January, February, March, and December of 2010, as well as from January of 2011 to investigate the changes in the carbon and nitrogen stable isotope ratios (${\delta}^{13}C$ and ${\delta}^{15}N$) and heavy metal with respect to it growth and to identify the factors that influence such changes. The blades of U. pinnatifida showed ${\delta}^{13}C$ and ${\delta}^{15}N$ in the range (mean) of -13.11 to -19.42‰ (-16.93‰) and 2.99 to 7.57‰ (4.71‰), respectively. Among samples with the same grow-out period, those that weighed more tended to have higher ${\delta}^{13}C$ suggesting a close association between the carbon isotope ratio and growth rate of U. pinnatifida. Indeed, we found a very high positive linear correlation between the monthly average ${\delta}^{13}C$ and the absolute growth rate in weight ($r^2=0.89$). Nitrogen isotope ratio tended to be relatively lower when nitrogen content in the blade was higher, probably due to the strengthening of isotope fractionation stemming from plenty of nitrogen in the surrounding environment. In fact, a negative linear correlation was observed with the nitrate concentration in the nearby seawaters ($r^2=0.83$). Concentrations of Cu, Cd, Pb, Cr, Hg, and Fe in the blades showed a rapid decrease in their concentration per unit weight in the more mature U. pinnatifida. Specifically, compared to adult samples, Cu, Hg, and Pb were concentrated by 30, 55, and 73 folds, respectively, in the young blades. Therefore, U. pinnatifida tissue ${\delta}^{13}C$ is as an indirect indicator of its growth rate, while ${\delta}^{15}N$ values and heavy metal concentrations serve as tracers that reflect the environmental characteristics.

• 한국간호교육학회지
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• 제6권2호
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• pp.327-344
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• 2000

The purpose of this survey study is to guide the direction of the RN-BSN program in Korea by analyzing (1) the philosophy and objectives (2) curriculum (3) and appraisal method, achievement test and self-directed learning. In this study, subjects consisted of 20 department of nursing in University and 20 RN-BSN programs in Korea. The Survey was conducted from September 1999 through May 2000 by mail and FAX. 1) Educational philosophy and objectives of 5 RN-BSN programs have curricular based philosophy. Most popular philosophies were revealed that nursing is oriented role function, human relation, and integrated application. 9 RN-BSN programs have curricular based objectives. There are including of knowledge, applying the new technology, under-standing of human being family community, application of nursing process, leadership, nursing ethics, and participation in research. 2) In RN-BSN programs, total mean credits through general college courses for earning the degree of BSN is 21.5 and total mean credits through the nursing area for earning the degree of BSN is 71.4. In RN-BSN programs, total mean credits through clinical practice for earning the degree of BSN is 5.94. 25.00 of mean credits was earned through achievement test(6.00~37.00). Therefore, this research suggests some recommendation for the development of curriculum of RN-BSN program that was required to do some alterations. And the various and other methods of earning credit should be developed. That is, the students will earn credits, accredited examination of University, advanced placement examination, case study, self-report, self-directed learning and achievement tests, portfolio review session and so on. And the RN-BSN courses are delivered to many areas by teleconferencing system, computer network(EdNet or Internet etc), CD-ROM Title, VOD (video on demand) and other methods.

• Clinical and Experimental Pediatrics
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• 제60권7호
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• pp.208-215
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• 2017

Purpose: Activation of Toll-like receptor 2 (TLR2) present on circulating monocytes in patients with Kawasaki disease (KD) can lead to the production of proinflammatory cytokines and interleukin-10 (IL-10). We aimed to determine the association of the frequency of circulating TLR2+/ CD14+ monocytes (FTLR2%) with the outcomes of KD, as well as to compare FTLR2% to the usefulness of sIL-10. Methods: The FTLR2% in patients with KD was measured by flow cytometry. Serum levels of IL-10 (sIL-10) were determined in 31 patients with KD before the initial treatment with intravenous immunoglobulin (IVIG) and in 21 febrile controls by using enzyme-linked immunosorbent assay. Patients were classified as having coronary artery lesions (CALs) based on the maximal internal diameters of the proximal right coronary artery and proximal left anterior descending coronary artery one month after the initial diagnosis. Results: We found that FTLR2% greater than 92.62% predicted CALs with 80% sensitivity and 68.4% specificity, whereas FTLR2% more than 94.61% predicted IVIG resistance with 66.7% sensitivity and 71.4% specificity. Moreover, sIL-10 more than 15.52 pg/mL predicted CALs and IVIG resistance with 40% and 66.7% sensitivity, respectively, and 73.7% and 76.2% specificity, respectively. Conclusion: We showed that measuring FTLR2% before the initial treatment could be useful in predicting CAL development with better sensitivity than sIL-10 and with results comparable to sIL-10 results for the prediction of IVIG resistance in patients with KD. However, further studies are necessary to validate FTLR2% as a marker of prognosis and severity of KD.

• Natural Product Sciences
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• 제26권1호
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• pp.50-58
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• 2020

The study was conducted for quantitive determination of macronutrients, micronutrients and heavy metals present in Spilanthes acmella Hutch and Dalz, a traditionally used important medicinal plant. The results illustrated the presence of substantial amounts of essential nutrient elements in different parts of the plant. K and Mg were detected in the range between 36.35 ± 1.01 to 67.78 ± 1.33 g/kg and 2.17 ± 0.13 to 7.02 ± 0.84 g/kg of DWS respectively. While the essential micronutrients Fe, Na, Mn, Zn and Cu were detected in the range between 62.62 ± 12.72 to 856.95 ± 76.61 mg/kg, 365.47 ± 23.84 to 633.03 ± 38.12 mg/kg, 51.66 ± 7.77 to 186.33 ± 13.92 mg/kg, 41.87 ± 2.85 to 53.89 ± 3.79 mg/kg and 18.49 ± 2.07 to 48.71 ± 4.89 mg/kg of DWS respectively. Besides, heavy metals (Cd, Ni and Pb) detected in some of the plant samples were beyond the maximum permissible limit (MPL) of FAO/WHO for herbal medicines. The concentrations of the essential nutrient elements except zinc were significantly different in different parts of the plant (p < 0.001). Further variation in the concentrations of the elements in the plant was observed with respect to seasonal changes and geographical conditions. Nevertheless the findings corroborate ethnomedicinal significance of the plant and signify the possibilibity of utilizing its standardized products for preparation of food supplements as well as multidimensional therapeutic herbal medicines.

• 생명과학회지
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• 제14권2호
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• pp.309-314
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• 2004

cAMP수용성 단백질(CRP)은 E. coli의 100가지 이상의 유전자 전자조절에 관계된다. CRP는 dimer로 존재하며 cAMP의 결합으로 활성인 형태로 전환된다. 이중체인 CRP 단백질의 열 안정성과 구조 전이의 연구에 효과적인 온도 기울기 전기영동장치를 이용하여 확인하였다. 본 연구에서 야생형과 S83C CRP 단백질의 melting temperature (Tm)는 산성인 완충용액[89.8 mM Glycine, 24mM Boric acid (pH 5.8)]에서 57$\pm$1(야생형 CRP)과 55$\pm$1$^{\circ}C$ (S83G CRP)였다. 그리고 온도에 따른 CRP 단백질의 구조변화도 protease digestion과 CD spectropolarimeter을 이용하여 확인하였다.

• 한국전자파학회논문지
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• 제12권1호
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• pp.71-76
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• 2001

Ka 대역 위성통신 및 BWLL 시스템용 3단 저잡음 증폭기가 MMIC 기술로 설계 및 제작되었다. MMIC 저잡음 증폭기는 잡음지수와 높은 이득 그리고 진폭 선형성을 만족하기 위하여 2단의 single-ended 형태의 증폭단과 1단의 balanced 형태의 증폭단으로 구성되었다. 낮은 잡음지수와 높은 이득을 얻기 위하여 0.15$\mu\textrm{m}$ pHEMT 소자가 사용되었다. CD에서 80 GHz 대역까지의 안정도 확보를 위하여 직렬 및 병렬 궤환 회로와 λ/4 short 라인이 삽입되었다. 설계된 MMIC 저잡음 증폭기의 크기는 3.1mm $\times$2.4mm(7.44mm$^2$)이다. 제작된 MMIC 저잡음 증폭기의 wafer 상에서의 측정 결과, 22~ 30 GHz 주파수 대역에서 잡음지수는 2.0 dB이하이고 이득은 26dB이상으로 설계 결과와 일치하였다.

• 한국토양비료학회지
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• 제48권1호
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• pp.64-71
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• 2015

Soil contamination with arsenic and heavy metals is a worldwide problem. Main objective of this research was to evaluated effects of reducing heavy metal leaching under reduced soil condition amended with industrial by-products. The contaminated soil was amended with 3% (w/w) of limestone (Ls), steel slag (SS) and acid mine drainage sludge (AMDS). Synthetic acid rain ($H_2SO_4:HNO_3=6:4$, pH 5.5 fixed) was used for feeding solution with flow rate of $0.78{\sim}0.88mL\;min^{-1}$. Results showed that similar pH and EC of leachate was observed in all treatments regardless of applied industrial by-products. However, arsenic concentration of leachate increased when industrial by-products were mixed. Meanwhile, concentration of heavy metal in the leachate decreased from 11.3 to 4.59 mg for Cd, from 92.3 to 7.93 mg for Pb, and from 11,716 to 1,788 mg for Zn via immobilization in soil with AMDS amended, respectively. Overall, application of industrial by-products can be an environmentally-friendly way to remediate soil and(or) leachate contaminated with metal(loid)s in metal mine site.

• Journal of Audiology & Otology
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• 제25권2호
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• pp.65-71
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• 2021

Background and Objectives: In masking level difference (MLD), the masked detection threshold for a signal is determined as a function of the relative interaural differences between the signal and the masker. Study 1 analyzed the results of school-aged children with good school performance in the MLD test, and study 2 compared their results with those of a group of children with poor academic performance. Subjects and Methods: Study 1 was conducted with 47 school-aged children with good academic performance (GI) and study 2 was carried out with 32 school-aged children with poor academic performance (GII). The inclusion criteria adopted for both studies were hearing thresholds within normal limits in basic audiological evaluation. Study 1 also considered normal performance in the central auditory processing test battery and absence of auditory complaints and/or of attention, language or speech issues. The MLD test was administered with a pure pulsatile tone of 500 Hz, in a binaural mode and intensity of 50 dBSL, using a CD player and audiometer. Results: In study 1, no significant correlation was observed, considering the influence of the variables age and sex in relation to the results obtained in homophase (SoNo), antiphase (SπNo) and MLD threshold conditions. The final mean MLD threshold was 13.66 dB. In study 2, the variables did not influence the test performance either. There was a significant difference between test results in SπNo conditions of the two groups, while no differences were found both in SoNo conditions and the final result of MLD. Conclusions: In study 1, the cut-off criterion of school-aged children in the MLD test was 9.3 dB. The variables (sex and age) did not interfere with the MLD results. In study 2, school performance did not differ in the MLD results. GII group showed inferior results than GI group, only in SπNo condition.

• 대한청각학회지
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• 제25권2호
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• pp.65-71
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• 2021

Background and Objectives: In masking level difference (MLD), the masked detection threshold for a signal is determined as a function of the relative interaural differences between the signal and the masker. Study 1 analyzed the results of school-aged children with good school performance in the MLD test, and study 2 compared their results with those of a group of children with poor academic performance. Subjects and Methods: Study 1 was conducted with 47 school-aged children with good academic performance (GI) and study 2 was carried out with 32 school-aged children with poor academic performance (GII). The inclusion criteria adopted for both studies were hearing thresholds within normal limits in basic audiological evaluation. Study 1 also considered normal performance in the central auditory processing test battery and absence of auditory complaints and/or of attention, language or speech issues. The MLD test was administered with a pure pulsatile tone of 500 Hz, in a binaural mode and intensity of 50 dBSL, using a CD player and audiometer. Results: In study 1, no significant correlation was observed, considering the influence of the variables age and sex in relation to the results obtained in homophase (SoNo), antiphase (SπNo) and MLD threshold conditions. The final mean MLD threshold was 13.66 dB. In study 2, the variables did not influence the test performance either. There was a significant difference between test results in SπNo conditions of the two groups, while no differences were found both in SoNo conditions and the final result of MLD. Conclusions: In study 1, the cut-off criterion of school-aged children in the MLD test was 9.3 dB. The variables (sex and age) did not interfere with the MLD results. In study 2, school performance did not differ in the MLD results. GII group showed inferior results than GI group, only in SπNo condition.