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Formation and Dissociation Kinetics of Zinc(II) Complexes of Tetraaza-Crown-Alkanoic Acids (Zinc(Ⅱ) Tetraaza-Crown-Allkanoic Acids 착물의 형성 및 해리 반응속도론)

  • Choi, Ki Young;Kim, Dong Won;Kim, Chang Suk;Park, Byung Bin;Choi, Suk Nam;Hong, Choon Pyo;Ryu, Hae Il
    • Journal of the Korean Chemical Society
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    • v.44 no.5
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    • pp.403-409
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    • 2000
  • The formation and dissociation rates of $Zn^{2+}$ Complexes with l,4,7,10-tetraaza-13,16-diox-acyclooctadecane-N,N',N",N'"-tetraacetic acid (1), 1,4,7,10-tetraaza-13,16- dioxacyclooctadecane-N,N',N",N'"-tetramethylacetic acid (2), and 1,4,7,10-tetraaza-13,16- dioxacyclooctadecane-N,N',N",N'"-tetrapropionic acid(3) have been measured by stopped-flow and conventional spectrophotometry. Observations were made at 25.0$\pm$0.1 $^{\circ}C$ and at an ionic strength of 0.10 M NaClO$_4$. The formation reactions of $Zn^{2+}$ ion with 1 and 2 took place by the rapid formation of an intermediate complex (ZnH$_3L^+$) in which the $Zn^{2+}$ ion is incompletely coor-dinated. This might then lead to be a final product in the rate-determining step.ln the pH range 4.76-5.76, the diprotonated (H2L2-) form is the kinetically active species despite of its low concentration. The stability con-stants (log$K_{(ZnH$_3$3$L^+$)}$) and specific water-assisted rate constants (koH) of intermediate complexes have been deter-mined from the kinetic data. The dissociation reactions of $Zn^{2+}$ complexes of 1,2, and 3 were investigated with $Cu^{2+}$ ions as a scavenger in acetate buffer. All complexes exhibit acid-independent and acid-catalyzed con-tributions. The effect of buffer and $Cu^{2+}$ concentration on the dissociation rate has also been investigated. The ligand effect on t dissociation rate of $Zn^{2+}$ complexes is discussed in terms of the side-pendant armsand the chelate ring sizes of the ligands.

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A Study on Awareness of Job Characteristics and Job Satisfaction of Landscape Architect Public Officials in Korea (조경직 공무원의 직무특성 및 직무만족 인식에 관한 연구)

  • Park, Tae-Seok;Kim, Shin-Won
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.6
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    • pp.148-161
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    • 2016
  • In the case of the government, which plays a pivotal role in the landscape architecture system, the management of positions in landscape architectural organizations is lacking. At the local government level, while public officials for managing landscape architecture are being hired, there are problems and vulnerabilities in both management and system operations as such public officials recruited for positions in landscape architectural services operate under the forestry service. Accordingly, this study analyzed the Korean administrative system of public officials in the landscape architectural service and their satisfaction with the organizational culture and behavior. The aim was to provide practical data for improving the job satisfaction of public officials in landscape architectural service and enhance the status of landscape architecture. First, a survey was conducted regarding current organizational culture/behavior and job adequacy, and differences when compared to different job series with regards to the public officials in the landscape architectural service. The results indicated that job satisfaction of those in landscape architectural service was generally high, but they showed strong centralization, i.e., orders from superiors and limitations on autonomy. Second, an analysis was conducted to improve the organizational culture/behavior and job satisfaction of public officials in the landscape architectural service, and a comparative analysis was conducted on the differences between the analysis result and preceding studies by the Ministry of Government Administration and Home Affairs(2006). The results indicated that organizational commitment/satisfaction of public officials in the landscape architectural service was relatively low among those who had a great amount of work experience related to forestry. Therefore, it was shown that it is necessary to ensure expertise in landscape architecture. Third, a comprehensive analysis was conducted regarding the influences on "working environment", "legal system" and "job allocation" in regard to public officials in land architectural service. The results indicated that satisfaction in the value system was high when given significance to the job as public officials in land architectural. However, their satisfaction in the land architectural system was low due to the lack of independence in their positions, the vulnerable legal system of land architectural service and low employment rates. Fourth, current public officials in landscape architectural service process tasks such as forestry, architecture, city planning and administration that are not related to their area of expertise. Therefore, an analysis was conducted on whether there is a difference in the job satisfaction of public officials in landscape architectural service according to statistical variables. It was identified that "legal system", "job satisfaction" and "organizational commitment" with regard to public officials in landscape architectural service can be improved through ensuring their expertise. This study suggests the following tasks to further inquire into landscape architecture in general. First, establish an identity of work allocation for public officials in the landscape architectural service, and second, establish an organizational constitution according to the positions in landscape architectural service. Accordingly, it is necessary for interested parties of landscape architecture to devise practical strategies so that such tasks can be converged administratively and reflected in policies.

Studies on the Sex Hormone Levels in Korean Native Goat during Puberty, Estrous Cycle and Pregnancy(II) -Changes of Sex Hormone Level throughout Estrous Cycle- (재래산양(在來山羊)의 성성숙(性成熟), 발정주기(發情週期) 및 임신기간(姙娠期間)에 따른 성(性) Hormone 수준(水準)의 변화(變化)에 관(關)한 연구(硏究)(II) -발정주기(發情週期)에 따른 혈청(血淸) 성(性) Hormone 수준(水準)의 변화(變化)-)

  • Lee, Kyu Seung;Park, Chang Sik;Kim, Hak Kyu
    • Korean Journal of Agricultural Science
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    • v.12 no.1
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    • pp.62-69
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    • 1985
  • The present study was carried out to determine sex hormone levels in serum throughout estrous cycle in Korean native goats. LH, FSH, prolactin, estradiol-$17{\beta}$ and progesterone in serum analyzed every 2 days from the estrus (day 0) to the 20th day of estrous cycle by the radioimmunoassay. The concentration of serum LH was high level with 3.27 mIU/ml on the day of estrus, then decreased rapidly to l.05~1.73 mIU/ml from the day 2 of estrous cycle to the day 18. A similar tendency was observed in the prolactin concentration, however the ranges of variation were not so marked as those of LH concentration. FSH concentrations determined were below 1.25 mIU/ml in all observation time. The concentration of serum estradiol-$17{\beta}$ was the highest, 23.62 pg/ml on the day of estrus, but the levels of 4.56~9.75 pg/ml were maintained during the other days of estrous cycle. Progesterone concentrations were the lowest, 0.45 ng/ml on the day of estrus and thereafter increased gradually to 8.85 ng/ml on the day 14 of estrous cycle, then decreased again. Serum LH concentrations before and after estrus maintained high levels during the 12 hours, i. e., 6 hours before and 6 hours after estrus. The concentrations of FSH were below 1.25 mIU/ml during the observation period. Prolactin concentrations were observed high levels during 24 hours, i.e., 12 hours before and 12 hours after estrus. Estradiol-$17{\beta}$ concentrations before and after estrus maintained high levels during the 24 hours, i.e., 12 hours before and 12 hours after estrus. The tendency of changes in progesterone concentrations were contrary to that of estradiol-$17{\beta}$.

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A Study on Glass Mirror Trade and its Characteristics of Craft after Joseon Dynasty (조선 후기 유리거울의 수입과 공예품의 특징)

  • Park, Jinkyung
    • Korean Journal of Heritage: History & Science
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    • v.52 no.4
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    • pp.206-225
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    • 2019
  • This paper examines the trade and development aspects of glass mirrors through the literature records of the Joseon Dynasty, and studies the characteristics of existing glass mirror crafts by referring to the terms and types shown in the literature. The glass mirror in the records had called western mirrors(西洋鏡, 洋鏡), glass mirrors(玻璃鏡, 玻瓈鏡), stone mirrors(石鏡), etc. Glass mirrors were imported mainly through trade with Russia and the Qing Dynasty since the 17th century and were banned from importation in the late Joseon Dynasty. These mirrors were something new that caused a great stirring in Joseon society in the 18th century, and in the 19th century, it grew larger as a commodity needed for everyday life, especially with trade with Japan. At that time, glass mirrors were used for various purposes, such as installing large glass at a store, which were not the standard mirror usage of confirming one's appearance. These mirrors surprised Koreans in Joseon who experienced them at Yanjing Liulichang(燕京 琉璃廠) in the 18th and 19th centuries. As a result, the demand for glass mirrors rapidly increased and quickly surpassed that of bronze mirrors. Consequentially, new crafts using glass mirrors instead of bronze mirrors in Joseon began to be produced and used after the 18th century. In particular, integrated flat boards of glass mirrors were developed as crafts used indoors. It was convenient to use the hair comb box, a long-time presence in Joseon society, with the bronze mirror. This kind of mirror remained apparent in various genre paintings, including the Taepyeong Seongsido(太平城市圖, 'A Thriving City in a Peaceful Era') collected the National Museum of Korea which reflect its populism of the times. Also, the Mirror Stand(鏡臺) used in the Qing Period was produced in Joseon, but there was a difference in the way of making the drawers and box shapes between two nations. On the other hand, the Face Mirror(面鏡) was made to look at the face. Various crafts made with the aesthetic sense of Joseon, such as the ox horn inlaying craft technique, were produced with auspicious designs. In the 19th century, glass mirrors were imported from European countries, such as France, Denmark, the Netherlands, and the United Kingdom, however after the end of the 19th century Japanese crafts were popular. Glass mirrors, which were popular in the Meiji and Taisho eras of Japan, were imported and also the Mirror Screen(鏡屛) using large glass mirrors were used. In particular, the mirror screen had developed wood furniture since the previous time, which were used for banquets and large spaces, such as the drawing room, and were imported from China and Japan. In addition, the western architectural effect of attaching a mirror to the wall was also attempted to adjust the brightness of the space and introduce another image and scenery in the mirror. This was done at Deoksugung Palace's Seokjojeon.

A Study on Personal Diaries in the Joseon Period (조선시대 개인 일기의 현황과 특징)

  • Lee, Jong-suk
    • Korean Journal of Heritage: History & Science
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    • v.52 no.4
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    • pp.142-153
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    • 2019
  • The Joseon Dynasty (1392-1910) left behind a wealth of documentary heritage, including collections of literary works, personal letters, and journals, as well as public documents such as Veritable Records of the Joseon Dynasty (Joseon Wangjo Sillok), Diaries of the Royal Secretariat (Seungjeongwon Ilgi), and State Protocols (Uigwe). Such heritage also includes personal diaries that have been highly regarded for their frank and vivid records of people's lives in the Joseon period. There have been great diaries published and intended for reading by the Korean public, including War Diaries (Nanjung Ilgi, 1592~1598) by Yi Sun-sin and Diaries of Jehol (Yeolha Ilgi, 1780) by Park Ji-won. Unfortunately, a great majority of these personal records remain unknown to the world. Such great records have not been given an opportunity to be documented properly, but are left outside public attention, abandoned to be damaged and destroyed. Few personal diaries of the Joseon period were written on good-quality paper. After the death of their authors, these diaries were left to be kept by their descendants; this explains why many of these records have been in poor condition, particularly when compared with the public records published by the government of Joseon, such as Sillok and Uigwe, even when these were lucky enough to be taken care of by the authors' descendants. Even after surviving a long time, many of these personal records remain in the form of manuscripts, written in semi-cursive and cursive scripts of Chinese characters, thus making it even more difficult for the people of the current generation -- most of whom have not been given an opportunity to learn Chinese characters at school -- to take care of their documentary heritage properly. Meanwhile, it is also true that, as the value of the public records published by the government of Joseon as historical materials has grown, they are used more often as content for TV dramas such as Daejanggeum. At the same time, there have been increasingly louder voices citing the need for the study, preservation, and management of the personal diaries from Joseon. Considering the situation, this study provides a general overview of the personal diaries of Joseon as recently surveyed by the National Research Institute of Cultural Heritage, as well as their characteristic features, subjects, and backgrounds. This study is expected to contribute to future research on the preservation and management of the personal diaries of Joseon.

Immune Cell Activation and Co-X-irradiation Effect of Eleutherococcus senticosus Maxim Root (가시오갈피 뿌리의 면역세포 활성 및 방사선 병용효과)

  • Kwon, Hyoung-Cheol;Park, Jeong-Seob;Choi, Dong-Seong
    • Radiation Oncology Journal
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    • v.25 no.3
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    • pp.185-191
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    • 2007
  • Purpose: This study was performed to investigate the effects of immune cell activation and the antitumor effect for the combination of treatment with X-irradiation and E/eutherococcus senticosus Maxim Root (ESMR) on mouse tumor cells. Materials and Methods: ESMR (250g) was extracted with 80% methanol, concentrated under decompression and lyophilized. To determine whether ESMR is able to activate the immune cells or not, the proliferation of splenocytes in vitro and the number of B cells and T cells in splenic lymphocytes in ESMR-pretreated mice were evaluated. X-irradiation was given to the mouse fibrosarcoma tumor cells (FSa II) by 250 kv X-irradiation machine. The cytotoxicity of ESMR was evaluated from its ability to reduce the clonogenecity of FSa II cells. In X-irradiation alone group, each 2, 4, 6 and 8 Gy was given to FSa II cells. In X-irradiation with ESMR group, 0.2 mg/ml of ESMR was exposed to FSa II cells for 1 hour before X-irradiation. Results: The proliferation of cultured mouse splenocytes and thymocytes were enhanced by the addition of ESMR in vitro. The number of B cells and T cells in mouse splenic lymphocytes was significantly increased in ESMR pretreated mice in vivo. In FSa II cells that received a combination of 0.2 mg/ml of ESMR with X-irradiation exposure, the survival fraction with a dose of 2, 4 and 6 Gy was $0.39{\pm}0.005$, $0.22{\pm}0.005$ and $0.06{\pm}0.007$, respectively. For FSa II cells treated with X-irradiation alone, the survival fraction with a dose of 2, 4 and 6 Gy was $0.76{\pm}0.02$, $0.47{\pm}0.008$ and $0.37{\pm}0.01$. The difference in the survival fraction of the mouse FSa II cells treated with and without ESMR was statistically significant (p<0.05). Conclusion: Treatment with ESMR increased cell viability of mouse splenocytes in vitro and especially the subpopulation of B cells and T cells in splenocytes in ESMR-pretreated mice. However, treatment with ESMR did not increase the level of Th and Tc subpopulations in the thymocytes. Treatment with the combination of ESMR and X-irradiation was more cytotoxic to mouse tumor cells than treatment with X-irradiation alone; this finding was statistically significant.

A Survey of Disease Occurrence in Korean Black Goats (흑염소 사육농가의 질병발생 실태조사)

  • Choe, Chang-Yong;Kang, Da-Won;Choi, Sun-Ho;Cho, Chang-Yeon;Jung, Byeong-Yeal;Son, Jun-Kyu;Ryu, Il-Sun;Hu, Tai-Young;Jung, Young-Hun;Kang, Seog-Jin;Do, Youn-Jeong;Kim, Ui-Hyung;Park, Yong-Sang;Son, Dong-Soo
    • Journal of Veterinary Clinics
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    • v.29 no.2
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    • pp.160-164
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    • 2012
  • The goat industry has been developing for many years in Korea to meet demands for food and medicine. However, many complicated patterns of disease have arisen in goat farms as this industry has developed. In this study, disease occurrence patterns in Korean black goats were surveyed in six professional farming households in Imsil and Soonchang in the Jeonbuk province and in Hamyang and Sachon in the Gyeongnam province to understand and extend the goat disease database. We observed morbidity rates between 2.0% and 9.8% for adult goats and between 2.9% and 68.3% for kids. Kids showed a markedly higher incidence of disease when compared to adults. The rate of disease occurrence was 40.0% for floppy kid syndrome (FKS), 37.7% for diarrhea, 16.0% for respiratory disease, and 1.9% for skin disease. The observed mortality rates were 0.7% ~ 10.0%, and 2.2% ~ 24.9% for adult goats and kids, respectively. In addition, FKS, diarrhea, and respiratory disease were observed in 38.3%, 28.9%, and 10.0%, respectively, of dead goats. In conclusion, the majority of diseases in goats occur during the neonatal period, and FKS is the highest single cause of mortality in Korean black goats. Thus careful attention must be paid to kids to reduce the goat mortality rate.

Effects of Sasa coreana Nakai on the Lipid Compositions of Serum in High Cholesterol Diet Rats (신의대(Sasa coreana Nakai) 추출물이 고콜레스테롤 식이 투여 흰쥐의 혈청 지질에 미치는 영향)

  • Park, Jong-Ok;Jang, Hye-Won
    • Journal of Life Science
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    • v.19 no.8
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    • pp.1145-1151
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    • 2009
  • This study was performed to investigate the effects of Sineui-Dae (Sasa coreana Nakai, a kind of bamboo) extracts on the improvement of serum lipid composition by using rats fed a hypercholesterol diet for 4 weeks. The experiment animals were administered with the following diets; high cholesterol diet group (HC diet) as a control and three supplemented groups with high cholesterol diets (HCW, HCM or HCH diet). Three kinds of extracts were prepared by orderly extraction with hexane, methanol, and water. We measured free cholesterol, cholesteryl ester, total cholesterol LDL- and HDL-cholesterol triglyceride and phospholipid in the serum of rats in three experimental and control groups. There were no significant differences in body weights and feed intakes between the HC control group and the extract supplemented groups. The levels of total cholesterol and LDL-cholesterol in the serum of extract supplemented groups were lower than that of the group fed with HC diet only. Serum HDL-cholesterol levet which is known as an antiatherosclerosis factor, was higher in all groups supplemented with bamboo extract by 17.2-21.9% compared to the HC control group. All groups supplemented with bamboo extracts showed the lowering effect of atherogenic index compared to the HC control group (HC group: 2.96${\pm}$0.08, HCM group: 1.48${\pm}$0.02, HCW group: 1.69${\pm}$0.04, HCH group: 1.84${\pm}$0.01). Furthermore, serum triglyceride and phospholipid decreased significantly in the HCM diet compared to the HC control diet. These results suggest that Sineui-Dae bamboo extract, especially methanol extract, has improving effects on hyperlipidemia of rats fed a high cholesterol diet.

The Effects of Medicinal Herb-made Sikhe on Damage and Lipid Levels of Liver in Rats Fed High-cholesterol Diets (한약제 추출물로 제조된 식혜가 고지방식이에 의한 흰주의 간 손상과 간 지질 함량에 미치는 영향)

  • Park, Hyun-Suk;Yang, Kyung-Chun;Yang, Kyung-Mi
    • Journal of Life Science
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    • v.19 no.8
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    • pp.1104-1111
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    • 2009
  • This study was conducted to evaluate the effect of Sikhe made by medicinal herb on the functional level of liver. Water extract I (12.9% W/W) and II (25.8% W/W) were obtained from medicinal materials: Caragana Sinica, Glycyrrhiza uralensis, Atractylodes rhizoma alba, Atractylodes rhizoma alba, Crataegus pinnatifida, Paeonia lactiflora Pasll., Hordeum vulgare Linne, Oryza sativa Linne, ginger, peer and jujube. Experimental groups were divided into the control diet group (C), high fat diet group (HF), high fat diet treated with 5% extract I group (HFE I ) and high fat diet treated with 5% extract II group (HFE II). In sensory evaluation, overall quality scores associated with color, aroma, flavor and taste were significantly higher in water extract II than in water extract 1. After investigating functional and lipid levels of livers in rats, we found that the administration of water extract I or water extract II to the high fat diet group (HF) did not affect the gain of body weight but mildly reduced GOT or GPT activity in the high diet group. Moreover, administration of these medicinal herbal extracts significantly decreased the levels of total lipid, triglyceride and total cholesterol in the high fat diet group (HF). However, administration of these medicinal herbal extracts did not affect the level of phospholipid. In conclusion, as Sikhe made by medicinal herb slightly decreased the activity of GOT or GPT and amount of lipid in liver, prevention against high fat diet is thought to be important for liver protection.

Components and Biological Activity of Aqueous Extract Isolated from Winged Stem of Euonymus alatus (화살나무 물 추출물의 구성성분과 생리활성)

  • Oh, Bong-Yun;Hwang, Soo-Kyung;Cheong, Mi-Young;Sin, Hong-Sig;Park, Bock-Hee;Lee, Jeong-Ho;Kim, Soo-Hyun
    • Korean Journal of Food Science and Technology
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    • v.37 no.6
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    • pp.898-904
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    • 2005
  • Although Euonymus alatus (EA) has been used as traditional medicine for cancer treatment, exact substances involved in curing of the disease are not yet known. Free radical scavenging and reactive oxygen species (ROS) removal activities of aqueous extract components isolated from winged stem of EA in animal cell line were investigated. Aqueous extract of EA (AEEA) was fractionated by ultrafiltration. All fractions mainly consisted of polysaccharide (44.8%), protein (2.1%), small amounts of phenol compounds and organic acids. Antioxidant activity of AEEA increased depending on concentration fractions, as determined by 1,1-diphenyl-2-picrylhydrazyl method. ROS removal activity was visualized in Chinese hamster ovary cell line using laser scanning confocal microscope, and AEEA activity increased in order of F IV>F III>F I>F II. These results suggest AETA has bioactive carbohydrates with potentials as functional foods and antioxidants.