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Modeling on the Sorption Kinetics of Lead and Cadmium onto Natural Sediments (퇴적물에서의 납과 카드뮴의 흡착 동력학 모델링)

  • Kwak, Mun-Yong;Ko, Seok-Oh;Park, Jae-Woo;Jeong, Yeon-Gu;Shin, Won-Sik
    • Korean Journal of Ecology and Environment
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    • v.39 no.4 s.118
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    • pp.450-461
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    • 2006
  • In this study, sorption kinetics of lead (Pb) and cadmium (Cd) onto coastal sediments were investigated at pH 5.5 using laboratory batch adsorbers. Four different models: one-site mass transfer model (OSMTM), pseudo-first-order kinetic model (PFOKM) ,pseudo-second-order kinetic model (PSOKM) and two compartment first-order kinetic model (TCFOKM) were used to analyze the sorption kinetics. As expected from the number of model parameters involved, the three-parameter TCFOKM was better than the two-parameter OSMTM, PFOKM and PSOKM in describing sorption kinetics of Pb and Cd onto sediments. Most sorption of Pb and Cd was rapidly completed within the first three hours, followed by slow sorption in the subsequent period of sorption. All models predicted that the sorbed amount at the apparent sorption ($q_{e,s}$) equilibria increased as the CEC and surface area of the sediments increased, regardless of initial spiking concentration ($C_0$) and heavy metal and the sediment type. The sorption rate constant ($k_s,\;hr^{-1}$) in OSMTM also increased as the CEC and BET surface area increased. The rate constant of pseudo-first-order sorption ($k_{p1,s},\;hr^{-1}$) in PFOKM were not correlated with sediment characteristics. The results of PSOKM analysis showed that the rate constant of pseudo-second-order sorption ($k_{p2,s},\;g\;mmol^{-1}\;hr^{-1}$) and the initial sorption rate ($v_{o,s},\;mg\;g^{-1}\;hr^{-1}$) were not correlated with sediment characteristics. The fast sorption fraction ($f_{1,s}$) in TCFOKM increased as CEC and BET surface increased regardless of initial aqueous phase concentrations. The sorption rate constant of fast fraction ($k_{1,s}=10^{0.1}-10^{1.0}\;hr^{-1}$) was much greater than that of slow sorption fraction ($k_{2,s}=10^{-2}-10^{-4}\;hr^{-1}$) respectively.

Seasonal Variations of Water Environments and Benthic Diatom Communities in Streams across Byeonsan-Bando and Seonunsan Parklands in Jeollabukdo, Korea (전라북도의 변산반도 국립공원과 선운산 도립공원 하천의 수환경과 부착규조류 군집의 계절적인 변화)

  • Park, Kyung-Woo;Kim, Yun-Sam;Park, Jung-Won;Jeune, Kyung-Hee;Kim, Mi-Kyung
    • Korean Journal of Ecology and Environment
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    • v.44 no.2
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    • pp.239-251
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    • 2011
  • To compare the different water environments in the Jigsaw stream (st. 1, 2) and Jujin stream (st. 3, 4) crossing over the Byeonsan-Bando and Seonunsan parklands, the physico-chemical factors and the species compositions of epilithic diatoms were analyzed from March 2009 to February 2010. The mean values of conductivity (681.1 ${\mu}S\;cm^{-1}$), suspended solids (27.83 mg $L^{-1}$), biological oxygen demand (3.15 mg $L^{-1}$), total nitrogen (3.24 mg $L^{-1}$), total phosphorus (0.24 mg $L^{-1}$) and chlorophyll-${\alpha}$ (12.99 mg $m^{-3}$ ) in Jujin stream were significantly higher than each element in Jigsaw stream. Eighty taxa were classified into 73 species and seven varieties belonging to 24 genera, eight families, three suborders and two orders in Jigsaw stream. Eighty eight taxa were classified into 81 species and seven varieties belonging to 22 genera, seven families, three suborders and two orders in Jujin stream. Biological water quality assessments revealed that Jigsaw stream was ${\beta}$~${\alpha}$-oligosaprobic and Jujin stream was ${\beta}$-mesosaprobic. Dominant and diversity indices were indicated from 0.25~0.81 and from 1.73~4.14 in Jigsaw stream, respectively, and from 0.29~0.64 and from 2.72~4.02 in Jujin stream, respectively. Jujin stream was more eutrophic than those of Jigsaw stream. The different water environments between the two streams could be due to the different ecosystems of the neighboring basins of each stream crossing over in the mountain. Further studies should investigate the water environments of two streams by continuous and regular monitoring to analyze the different ecosystem mechanisms.

Occupational Demands and Educational Needs in Korean Librarianship (한국적 도서관학교육과정 연구)

  • Choi Sung Jin;Yoon Byong Tae;Koo Bon Young
    • Journal of the Korean Society for Library and Information Science
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    • v.12
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    • pp.269-327
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    • 1985
  • This study was undertaken to meet more fully the demands for improved training of library personnel, occasioned by the rapidly changing roles and functions of libraries as they try to adapt to the vast social, economic and technological changes currently in progress in the Korean society. The specific purpose of this research is to develop a standard curriculum at the batchelor's level that will properly equip the professional personnel in Korean libraries for the changes confronting them. This study started with the premise that to establish a sound base for curriculum development, it was necessary first to determine what concepts, knowledge, and techniques are required for professional library personnel to perform it at an optimal level of efficiency. Explicitly, it was felt that for the development of useful curricula and courses at the batchelor's level, a prime source of knowledge should be functional behaviours that are necessary in the job situation. To determine specifically what these terminal performance behaviours should be so that learning experience provided could be rooted in reality, the decision was reached to use a systems approach to curriculum development, which is an attempt to break the mold of traditional concepts and to approach interaction from an open, innovative, and product-oriented perspective. This study was designed to: (1) identify what knowledge and techniques are required for professional library personnel to perform the job activities in which they are actually engaged, (2) to evaluate the educational needs of the knowledge and techniques that the professional librarian respondents indicate, and (3) to categorise the knowledge and techniques into teaching subjects to present the teaching subjects by their educational importance. The main data-gathering instrument for the study, a questionnaire containing 254 items, was sent to a randomly selected sample of library school graduates working in libraries and related institutions in Korea. Eighty-three librarians completed and returned the questionnaire. After analysing the returned questionnaire, the following conclusions have been reached: (A) To develop a rational curriculum rooted in the real situation of the Korean libraries, compulsory subjects should be properly chosen from those which were ranked highest in importance by the respondents. Characters and educational policies of, and other teaching subjects offered by, the individual educational institution to which a given library school belongs should also be taken into account in determining compulsory subjects. (B) It is traditionally assumed that education in librarianship should be more concerned with theoretical foundations on which any solution can be developed than with professional needs with particulars and techniques as they are used in existing library environments. However, the respondents gave the former a surprisingly lower rating. The traditional assumption must be reviewed. (C) It is universally accepted in developing library school curricula that compulsory subjects are concerned with the area of knowledge students generally need to learn and optional subjects are concerned with the area to be needed to only those who need it. Now that there is no such clear demarcation line provided in librarianship, it may be a realistic approach to designate subjects in the area rated high by the respondents as compulsory and to designate those in the area rated low as optional. (D) Optional subjects that were ranked considerably higher in importance by the respondents should be given more credits than others, and those ranked lower might be given less credits or offered infrequently or combined. (E) A standard list of compulsory and optional subjects with weekly teaching hours for a Korean library school is presented in the fourth chapter of this report.

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A Study on the Transformation of Traditional Laboratories into Instructional Media Centers for Education of Library and Information Science (문헌정보학 실습실의 교수매체 센터화에 관한 연구)

  • Lee, Man-Soo
    • Journal of the Korean Society for Library and Information Science
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    • v.34 no.1
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    • pp.265-295
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    • 2000
  • Education of library and information science must focus on practical education acted upon as a laboratory room in the characteristics of learning, because it cultivates a librarian as an information expert who can conduct professional affairs and services, applying traditional theory to the practical business of library and information. This dissertation suggested a new paradigm of an instructional media center as an advanced laboratory room which faithfully can run the curriculum of a library and information science for cultivating librarians, information experts who can satisfy the 21C information society. To carry out this purpose, I considered the various opinions of professors and librarians, after investigating and analyzing facilities and furnishings of laboratory rooms and teaching and learning data related to departments of library and information science in 32 universities. These contents can be summarized as follows : 1) Constructional media centers connected to education of library and information science sets laboratory rooms for practical classification and cataloging classes; laboratory rooms for film media which can utilize advanced media, listening tools, and practical materials; information management laboratory rooms which can experience the various information research methods through the Internet, cultivate the ability of information application, and teach the curriculum of library and information science related to computers. 2) Arrangement plans linked to laboratory rooms for classification and cataloging, one for film media, and one for information proceedings are as follows: , , and . 3) The size of each room is $162m^2$ (49.1pying); the number of persons to be admitted is about 40 to 50; each room has one media expert and one assistant as operating manager of exclusive responsibility. 4) Instructional & learning data which must be contained as instructional media of library and information science include computers, marginal tools related to it, listening materials, supplies for ordering books, teaching aids containing various equipment and tools, textbooks for practice, books connected to classification and cataloging for practice, and textbooks related to practical subjects and reference books. 5) Industrial media centers belonging to library and information science require for practice, general furnishings like bookshelves, and various material depository boxes.

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The Optimal Activation State of Dendritic Cells for the Induction of Antitumor Immunity (항종양 면역반응 유도를 위한 수지상세포의 최적 활성화 조건)

  • Nam, Byung-Hyouk;Jo, Wool-Soon;Lee, Ki-Won;Oh, Su-Jung;Kang, Eun-Young;Choi, Yu-Jin;Do, Eun-Ju;Hong, Sook-Hee;Lim, Young-Jin;Kim, Ki-Uk;Jeong, Min-Ho
    • Journal of Life Science
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    • v.16 no.6
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    • pp.904-910
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    • 2006
  • Dendritic cells (DCs) are the only antigen presenting cells (APCs) capable of initiating immune responses, which is crucial for priming the specific cytotoxic T lymphocyte (CTL) response and tumor immunity. Upon activation by DCs, CD4+ helper T cells can cross-prime CD8+ CTLs via IL-12. However, recently activated DCs were described to prime in vitro strong T helper cell type 1 $(Th_1)$ responses, whereas at later time points, they preferentially prime $Th_2$ cells. Therfore, we examined in this study the optimum kinetic state of DCs activation impacted on in vivo priming of tumor-specific CTLs by using ovalbumin (OVA) tumor antigen model. Bone-marrow-derived DCs showed an appropriate expression of surface MHC and costimulatory molecules after 6 or 7-day differentiation. The 6-day differentiated DCs pulsed with OVA antigen for 8 h (8-h DC) and followed by restimulation with LPS for 24 h maintained high interleukin (IL)-12 production potential, accompanying the decreased level in their secretion by delayed re-exposure time to LPS. Furthermore, immunization with 8-h DC induced higher intracellular $interferon(IFN)-{\gamma}+/CD8+T$ cells and elicited more powerful cytotoxicity of splenocytes to EG7 cells, a clone of EL4 cells transfected with an OVA cDNA, than immunization with 24-h DC. In the animal study for the evaluation of therapeutic or protective antitumor immunity, immunization with 8-h DC induced an effective antitumor immunity against tumor of EG7 cells and completely protected mice from tumor formation and prolonged survival, respectively. The most commonly used and clinically applied DC-based vaccine is based on in vitro antigen loading for 24 h. However, our data indicated that antigen stimulation over 8 h decreased antitumor immunity with functional exhaustion of DCs, and that the 8-h DC would be an optimum activation state impacted on in vivo priming of tumor-specific CTLs and subsequently lead to induction of strong antitumor immunity.

Quality Characteristics of Dolsan Leaf Mustard Kimchi Added with Seasoning of Sea tangle and Lentinus edodes (다시마와 표고버섯 혼합조미농축액 첨가에 따른 돌산갓김치의 품질특성)

  • Oh, Sun-Kyung;Kim, Ki-Woong;Park, Wook-Min;Kim, Nam-Hee;Bae, Sang-Ok;Choi, Myeong-Rak
    • Journal of Life Science
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    • v.25 no.5
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    • pp.557-567
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    • 2015
  • To increase the marketability of Dolsan leaf mustard Kimchi, seasonings were prepared by sea tangle and Lentinus edodes. Gat Kimchi A (GK-A) and Gat Kimchi B (GK-B) were prepared by addition of complex seasoning with Sea tangle (CSS), complex seasoning with Lentinus edodes (CSL), respectively and evaluated the quality characteristics. GK-A contained high minerals and dietary fiber and showed the effect of delaying pH-lowering and acidity-rising. There were no significant differences in salinity test after 70 days. Reducing sugar of test groups was higher than control. During the fermentation, Leuconostoc sp. was grown in GK-A and GK-B than control. Growth of control's Lactobacillus sp. increased 20 days after. Up to 30 days, lightness of control was high. Yellowness were increased browning potential in GK-B, 20 days after. From the initial to 10 days, Hardness of GK-A showed higher than the others. glutamic acid and aspartic acid content of GK-A was higher significantly than the others in the entire fermentation period (p<0.05). At 0, 10, 30 days, sweet-tasty amino acids of GK-A showed a significantly higher level than the others (p<0.05). From 10 days to 40 days of fermentation, the sensory evaluation of GK-A is better than the other groups. Comprehensively reviewed the above results, the conclusion is as follows: CSS made with sea tangle as a main ingredient. GK-A by seasoning the CSS to 90 g GK-A is expected as a new Dolsan leaf mustard products that can provide flavor and nutrition to the consumer at the same time.

Role of Alveolar Macrophages in Productions of Prostaglandin D2 and E2 in the Inflamed Lung (프로스타글란딘 D2와 E2의 생성에 대한 허파 마크로파이지의 역할)

  • Joo, Myung-Soo
    • Journal of Life Science
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    • v.20 no.6
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    • pp.845-852
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    • 2010
  • Our previous study showed that lungs infected by Pseudomonas, a gram-negative bacteria, produce prostaglandin $D_2$ ($PGD_2$) and prostaglandin $E_2$ ($PGE_2$), the two major prostanoids generated by cyclooxygenase-2 (COX-2), and that the ratio of $PGD_2$ and $PGE_2$ can affect the outcome of the bacterial lung infection. In this study, we sought to uncover the mechanism that determines the ratio of $PGD_2$ and $PGE_2$ produced in lung inflammation. When treated with lipopolysaccharide (LPS), primary alveolar macrophages, extracted from mouse lung, more $PGE_2$ was produced than $PGD_2$, whereas MH-S, a murine alveolar macrophage cell line, produced more $PGD_2$ than $PGE_2$ in a similar experiment. Western blot analyses showed that the kinetics of COX-2 expression in both cell types is similar and epigenetic silencing of COX-2 expression did not affect expressions of lipocalin-PGD synthase (L-PGDS) and PGE synthase (mPGES-1), major enzymes synthesizing $PGD_2$ and $PGE_2$ in inflammation, respectively, indicating no effect of COX-2 on expressions of the two enzymes. Expressions of L-PGDS and mPGES-1 were also similar in both cell types, suggesting no effect of the two key enzymes in determining the ratio of $PGD_2$ and $PGE_2$ in these cells. A single intraperitoneal injection of LPS to C57BL/6 mice induced COX-2 expression and, similar to alveolar macrophages, produced more $PGE_2$ than $PGD_2$ in the lung. These results suggest that the differential expressions of $PGD_2$ and $PGE_2$ in the lung reflect those in alveolar macrophages and may not be directly determined by the enzymes responsible for $PGD_2$ and $PGE_2$ synthesis.

Biological Activities of Pharbitis nil and Partial Purification of Anticancer Agent from Its Extract (견우자의 생리활성 분석과 추출물로부터 항암 활성물질의 분리)

  • Choi, Hyeun Deok;Yu, Sun Nyoung;Park, Sul-Gi;Kim, Young Wook;Nam, Hyo Won;An, Hyun Hee;Kim, Sang Hun;Kim, Kwang-Youn;Ahn, Soon Cheol
    • Journal of Life Science
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    • v.27 no.2
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    • pp.225-232
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    • 2017
  • This study aimed to evaluate several biological activities of Pharbitis nil and to isolate an anticancer agent from its methanol extract. Pharbitis nil seeds were extracted with methanol (PNM). Then, PNM was fractionated into solvent layers such as ethyl acetate fraction (PNE), butanol fraction (PNB), and water fraction (PNW). The biological activities of the fractions were analyzed for tyrosinase inhibition, lipase inhibition, DPPH-free radical scavenging, and cell growth inhibition. PNM showed strong growth inhibition of prostate cancer PC-3 cells. PNM was subjected to Diaion HP-20 and eluted stepwise with 50%, 80%, and 100% methanol. Then, for activity-guided fraction, each fraction was analyzed for growth inhibition of prostate cancer PC-3 cells by using an MTT assay. Because the 100% fraction showed significantly strong inhibitory activity, the fraction was further separated in the reverse phase C18, which was eluted with 80% and 90% methanol. The 90% fraction was further subjected to Sephadex LH-20 using a mobile solvent of 100% methanol. Finally, the compound PN was partially purified for HPLC analysis. PN showed cell growth inhibitory activity and induced the apoptosis and cell cycle arrest of prostate cancer PC-3 cells, as measured by flow cytometry. The results together suggest that Pharbitis nil possesses various biological activities, especially the inhibitory activity for the proliferation of prostate cancer PC-3 cells, suggesting the possibility of its use as an anticancer agent.

Identification of Antioxidant Compound Derived from Methanolic Extract of Houttuynia Cordata (어성초 메탄올 추출물로부터 항산화 효능을 가진 활성물질의 확인)

  • Kim, Hyeji;Hwang, Heesung;Park, Sumin;Kang, Sungwook;Kim, Hyejeong;Hong, Sugyeong;Kim, Moon-Moo;Oh, Yunghee
    • Journal of Life Science
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    • v.27 no.7
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    • pp.796-804
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    • 2017
  • This study was carried out to evaluate the antioxidant effect of methanolic extract of Houttuynia cordata (HCME) and to identify a compound having antioxidant effect. The ethyl acetate fraction of HCME showed the highest antioxidant effect in organic solvent fractions. The fraction was then separated into 12 fractions by open column chromatography. Among these fractions, the fraction 10 (Fr. 10) with the highest antioxidant activity was isolated, and its antioxidant effect was evaluated by DPPH radical scavenging activity, reducing power, TBARS, cell viability, DNA oxidation and DCF fluorescence. The Fr. 10 at a $64{\mu}g/ml$ showed 60% of inhibitory effect similar to that of vitamin C at $10{\mu}g/ml$, compared with blank group. The Fr. 10 at $64{\mu}g/ml$ showed 264% of reducing power, compared with blank group. TBARS assay showed that the Fr. 10 at $64{\mu}g/ml$ had 35.5% of inhibitory effect similar to that of vitamin E at $1,000{\mu}g/ml$, compared with blank group. The Fr. 10 above $32{\mu}g/ml$ displayed cytotoxicity. However, it was observed that the Fr. 10, above $1{\mu}g/ml$ reduced DNA damage. DCF fluorescence assay showed that the Fr. 10 inhibited oxidative stress by $H_2O_2$ in a dose dependent manner. The compound of Fr. 10 was identified to be rutin whose molecular weight is 610 by the IR and LC-MS analyses. Therefore, these results suggest that the rutin of Fr. 10 could use as a natural antioxidant for development of cosmetics and functional foods.

Active Aging: Roles of Physical Activity and Immunity (건강한 노후 : 운동활동과 면역반응을 중심으로)

  • Park, Chan Ho;Kim, Ji-Seok;Kwak, Yi Sub
    • Journal of Life Science
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    • v.28 no.5
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    • pp.621-626
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    • 2018
  • We introduced the physiological responses of aging, active aging and also suggest the impact of physical exercise on body health status and elderly immunity. In this purpose, we searched the Pub Med data base for the articles (include our experimental papers) and review papers having the terms 'Aging', 'Active aging' and 'Physical activity and elderly' in the title, published from 1999 until 2018. The results were as follows: Exercise training has been extensively studied about the reduction of inflammation, oxidative stress, disease, and aging in syndrome X patients and elderly. Combined and aerobic or resistance exercise training could reduce obesity, insulin resistance, type 2 diabetes and hypertension. Exercise training has been extensively studied in cancer settings as part of prevention or treatment strategies. From this research, regular exercise has the potential to target tumor growth through regulation of inflammation and immune responses such as lactate clearance, NK cell activation (innate immunity), activation of cytotoxic immune cells, T cell activation (adaptive immunity), and immune surveillance. However, Endurance physical activity not only induces thermogenesis and diverse sports injuries but also elicits mobilization and functional enhancement of monocytes, neutrophils (which is caused by the cytokine changes such as TNF-alpha, IL-1) whereas it suppresses cell mediated immunity causing to increased susceptibility to inflammation and infections like cough and URTIs (upper respiratory track infections) in young and especially in elderly people. Therefore, Strategies to prevent physical fatigue, sports injuries include avoid overtraining, Adequate recovery and various type of rest during and after physical activity and assuring adequate nutrition supplementation such as glutamine, vitamin B, vitamin C, carbohydrate, ion or berry-contain sports beverages is helpful in physically active elderly.