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An Early-Maturing, Blast Resistant and High Quality Rice Cultivar "Pyeongwon" (벼 조생 단간 내도열병 고품질 신품종 "평원")

  • Ryu, Hae-Young;Jeon, Yong-Hee;Jung, Kuk-Hyun;Shin, Young-Seop;Hwang, Hung-Goo;Kim, Hong-Yeol;Kim, Myeong-Ki;Jung, O-Young;Won, Yong-Jae;Kim, Yeon-Gyu;Yang, Chang-In;Lee, Jeom-Ho;Lee, Jeong-Il;Lee, Jeong-Heui;Choi, Yoon-Hee;Yang, Sae-Jun;Ahn, Eok-Keun
    • Korean Journal of Breeding Science
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    • v.41 no.2
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    • pp.177-181
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    • 2009
  • 'Pyeongwon' is a new japonica rice cultivar which is developed from a cross between Jinbu19 and Samjiyeon4 from North Korea by the rice breeding team of National Institute of Crop Science, RDA. Pyeongwon has about 107 days duration from seeding to heading in mid-northen plain, alpine, north-eastern coastal and southern alpine areas. It has about 67 cm culm length and tolerance to lodging. Pyeongwon has 13 tillers per hill and 82 spikelets per panicle. It showed tolerance to heading delay and spikelet sterility due to cold treatment similar to Odaebyeo. It also showed slow leaf senescence and moderate tolerance to viviparous germination during the ripening stage. Pyeongwon has resistance to blast disease but susceptible to stripe virus and brown planthopper. Milled rice of Pyeongwon has translucent kernels, relatively clear non-glutinous endosperm and medium short grain. It is characterized as a low gelatinization temperature and slightly lower amylose content (17.1%) variety compared to Odaebyeo (19.5%) and has good palatability of cooked rice. The milled rice yield performance of this cultivar was about 5.28 MT/ha by ordinary culture in local adaptability test for three years. This cultivar may be highly adaptable to the mid-northen plain, alpine, north-eastern coastal and southern alpine areas of Korea.

Clozapine Administration Potentiate Platelet Activation in Patients with Schizophrenia : Retrospective Study (클로자핀을 투여한 조현병 환자에서 혈소판 활성 증가에 관한 후향적 연구)

  • Kim, Hyun-Ah;Lee, Jong Wook;Kim, Seung-Jun;Oh, Hong-Seok;Im, Woo Young;Kim, Ji-Woong
    • Korean Journal of Psychosomatic Medicine
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    • v.26 no.2
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    • pp.188-193
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    • 2018
  • Objectives : Clozapine is a widely prescribed antipsychotic drug for schizophrenia and is known to increase the risk of cardiovascular disease due to its metabolic side effects. However, little is known about the effect of clozapine on the platelet activation, another important factor in the development of cardiovascular disease. In this study, we tried to investigate the effect of clozapine on platelet activity in patients with schizophrenia by comparing the mean platelet component (MPC) values before and after the clozapine administration. Methods : A retrospective review of medical records of patients with schizophrenia, who newly started clozapine treatment from September 1st, 2003 to April 30th, 2007 at the Department of Psychiatry, Konyang University Hospital in Republic of Korea was performed. The final statistical analysis included 14 participants. Bayer ADVIA $120^{(R)}$ system was used to measure MPC. Results : Among the 14 participants, five subjects were males (28.60%), and ten subjects were females (71.40%). The mean age of participants was $37.50{\pm}11.64years$. Average of duration of illness was $91.00{\pm}93.96months$, with the mean dosage of clozapine taken by participants at the time of the last blood test was $337.50{\pm}109.52mg$. The mean MPC measurement before and after receiving clozapine was $26.12{\pm}2.22g/dL$ and $25.14{\pm}2.08g/dL$ respectively. Wilcoxon signed rank test showed that there was a statistically significant decrease in MPC levels after clozapine administration (V=16, p=0.024). Conclusions : Decreased MPC levels after clozapine administration implies that clozapine may increase platelet activation which could have an adverse effect on the occurrence of thromboembolic disease. Our findings also suggest that careful monitoring of the risk factors of cardiovascular diseases, such as platelets activity, is necessary when administering clozapine.

Analysis of Central Line-associated Bloodstream Infection among Infants in the Neonatal Intensive Care Unit: A Single Center Study

  • Kim, Minhye;Choi, Sujin;Jung, Young Hwa;Choi, Chang Won;Shin, Myoung-jin;Kim, Eu Suk;Lee, Hyunju
    • Pediatric Infection and Vaccine
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    • v.28 no.3
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    • pp.133-143
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    • 2021
  • Purpose: This study aimed to determine the incidence of central line-associated bloodstream infection (CLABSI) in the neonatal intensive care unit (NICU), evaluate the patients' clinical characteristics, and identify the etiologic agents for guidance in prevention and treatment. Methods: A retrospective chart review study of infants classified as having CLABSI was conducted at the NICU of Seoul National University Bundang Hospital from January 2016 to December 2020. Results: Of the 45 infants, 53 had CLABSIs within a follow-up period of 18,622 catheter days. The incidence of CLABSIs was 2.85 per 1,000 catheter days. The most common catheter type was a peripherally inserted central catheter (n=47, 81%). A total of 57 pathogens were isolated, of which 57.9% (n=33) were Gram-positive bacteria, 36.8% (n=21) were Gram-negative bacteria, and 5.3% (n=3) were Candida spp. The most common pathogens were Staphylococcus aureus (n=12, 21%) and coagulase-negative staphylococci (n=12, 21%), followed by Klebsiella aerogenes (n=8, 14%). The median duration of bacteremia was 2 days, and 19 episodes showed bacteremia for 3 days or more. The mortality rate of infants within 14 days of CLABSI was 13.3% (n=6). Conclusions: This study analyzed the incidence of CLABSI and the distribution of pathogens in the NICU. Continuous monitoring of CLABSI based on active surveillance serves as guidance for empiric antibiotic use and also serves as a tool to assess the necessity for implementation of prevention strategies and their impact.

Study of Spatiotemporal Variations and Origin of Nitrogen Content in Gyeongan Stream ( 경안천 내 질소 함량의 시공간적 변화와 기원 연구)

  • Jonghoon Park;Sinyoung Kim;Soomin Seo;Hyun A Lee;Nam C. Woo
    • Economic and Environmental Geology
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    • v.56 no.2
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    • pp.139-153
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    • 2023
  • This study aimed to understand the spatiotemporal variations in nitrogen content in the Gyeongan stream along the main stream and at the discharge points of the sub-basins, and to identify the origin of the nitrogen. Field surveys and laboratory analyses, including chemical compositions and isotope ratios of nitrate and boron, were performed from November 2021 to November 2022. Based on the flow duration curve (FDC) derived for the Gyeongan stream, the dry season (mid-December 2021 to mid-June 2022) and wet season (mid-June to early November 2022) were established. In the dry season, most samples had the highest total nitrogen(T-N) concentrations, specifically in January and February, and the concentrations continued to decrease until May and June. However, after the flood season from July to September, the uppermost subbasin points (Group 1: MS-0, OS-0, GS-0) where T-N concentrations continually decreased were separated from the main stream and lower sub-basin points (Group 2: MS-1~8, OS-1, GS-1) where concentrations increased. Along the main stream, the T-N concentration showed an increasing trend from the upper to the lower reaches. However, it was affected by those of the Osan-cheon and Gonjiamcheon, the tributaries that flow into the main stream, resulting in respective increases or decreases in T-N concentration in the main stream. The nitrate and boron isotope ratios indicated that the nitrogen in all samples originated from manure. Mechanisms for nitrogen inflow from manure-related sources to the stream were suggested, including (1) manure from livestock wastes and rainfall runoff, (2) inflow through the discharge of wastewater treatment plants, and (3) inflow through the groundwater discharge (baseflow) of accumulated nitrogen during agricultural activities. Ultimately, water quality management of the Gyeongan stream basin requires pollution source management at the sub-basin level, including its tributaries, from a regional context. To manage the pollution load effectively, it is necessary to separate the hydrological components of the stream discharge and establish a monitoring system to track the flow and water quality of each component.

Effects of Magnetite(Fe3O4) as Electrical Conductor of Direct Interspecies Electron Transfer on Methane Yield of Food Wastewater (종간직접전자전달 전도체로서 Magnetite(Fe3O4)가 음폐수의 메탄생산에 미치는 영향)

  • Jun-Hyeong Lee;Tae-Bong Kim;Chang-Hyun Kim;Young-Man Yoon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.31 no.1
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    • pp.15-26
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    • 2023
  • Methane production by anaerobic digestion occurs through interspecies electron transfer (DIET), a synthetic metabolism between acetic and methanate bacteria through hydrolysis and acid production steps. In this study, to improve methane yield, the effect of addition of magnetite (Fe3O4), a conductor promoting DIET on methane production in food wastewater was investigated, and the effect on methane yield was assessed by methane potential (Bu) and maximum methane production rate [Rm(t0)] by the operation of batch type anaerobic reactor adding Fe3O4. The Bu and Rm(t0) of food wastewater without Fe3O4 were 0.496 Nm3/kg-VSadded and 38.24 mL/day, respectively. The t0 which reached to Rm appeared at 21.06 days during the operation of the anaerobic reactor. The Bu of food wastewater with Fe3O4 was 0.502, 0.498, 0.512, 0.510, 0.518, 0.523, 0.524, 0.540, and 0.549 Nm3/kg-VSadded in the treatment of 5, 10, 15, 20, 25, 30, 40, 70, and 100mM-Fe3O4, respectively, and the Bu significantly increased to 36.95% with the addition of magnetite in the addition of 15mM-Fe3O4. And, the addition of Fe3O4 shortened the duration to reach Rm from 21.06 days to the maximum of 14.67 days by the addition of Fe3O4. Therefore, the methane yield and production rate of food wastewater significantly improved with the addition of Fe3O4.

Treatment Effect with Weekly Teriparatide in the Vertebral Compression Fractures in Patients with Severe Osteoporosis (심한 골다공증 환자에서 발생한 척추체 압박골절에 대한 주 단위 테리파라타이드(Teriparatide)의 투여 효과)

  • Hwang, Seok-Ha;Woo, Young-Kyun;Jeon, Ho-Seung;Suh, Seung-Pyo;Kim, Joo-Young;Kim, Jae-Nam
    • Journal of the Korean Orthopaedic Association
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    • v.54 no.6
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    • pp.528-536
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    • 2019
  • Purpose: This study examined the effects of a weekly teriparatide on the change in vertebral compression ratio, back pain, and vertebral fracture healing in osteoporosis patients with vertebral compression fractured induced by low energy trauma. Materials and Methods: From January 2016 to December 2017, 57 patients with severe osteoporotic vertebral fractures with a T score of -3.5 or less were included in this study. The changes in the vertebral compression ratio, visual analogue scale (VAS), Oswestry disability index (ODI) for at least 6 months were examined. The morphology of bone marrow edema and the presence of intervertebral cleft, osteocalcin, and N-terminal telopeptide (NTx) were also investigated. Results: The mean compression ratio was 20% in the experimental group (teripratide group) at 3 months, and 38% in the control group. A significant difference in the compression ratio of the vertebral body over time was observed (p<0.05; t-test). A comparison of the compression ratio of the vertebral body with the follow-up duration in each group showed no significant increase in the, compression (p=0.063) in the experimental group and a significant increase in the control group (p<0.05). The mean time to reach the plateau of the compression rate was one month in the experimental group and three months in the control group. The VAS score in the experimental and control group was 0.39 and 1.07 points, respectively. The ODI score in the experimental and control group was 33.72 and 39.52, respectively. At the last follow-up radiographs, there were no cases with an intervertebral cleft (0%) in the experimental group and 1 case (2.2%) in the control group. A significant difference in the osteocalcin level was observed between the injury and 6 months after the injury (p=0.003). In addition, there was no significant difference in the NTx level between the injury and 6 months after injury (p=0.960). Conclusion: In vertebral compression fractures patients with severe osteoporosis, a weekly teriparatide can promote the union of fractures, prevent further collapse of the vertebral body, and reduce the back pain faster.

National Survey of Mycobacterial Diseases Other Than Tuberculosis in Korea (비결핵항산균증 전국 실태조사)

  • 대한결핵 및 호흡기학회 학술위원회
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.3
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    • pp.277-294
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    • 1995
  • Background: The prevalence of tuberculosis in Korea decreased remarkably for the past 30 years, while the incidence of disease caused by mycobacteria other than tuberculosis is unknown. Korean Academy of Tuberculosis and Respiratory Diseases performed national survey to estimate the incidence of mycobacterial diseases other than tuberculosis in Korea. We analyzed the clinical data of confirmed cases for the practice of primary care physicians and pulmonary specialists. Methods: The period of study was from January 1981 to October 1994. We collected the data retrospectively by correspondence with physicians in the hospitals that referred the specimens to Korean Institute of Tuberculosis, The Korean National Tuberculosis Association for the detection of mycobacteria other than tuberculosis. In confirmed cases, we obtained the records for clinical, laboratory and radiological findings in detail using protocols. Results: 1) Mycobacterial diseases other than tuberculosis were confirmed that 1 case was in 1981, 2 cases in 1982, 4 cases in 1983, 2 cases in 1984, 5 cases in 1985, 1 case in 1986, 3 cases in 1987, 1 case in 1988, 6 cases in 1989, 9 cases in 1990, 14 cases in 1990, 10 cases in 1992, 4 cases in 1993, and 96 cases in 1994. Cases since 1990 were 133 cases(84.2%) of a total. 2) Fifty seven percent of patients were in the age group of over 60 years. The ratio of male to female patients was 2.6:1. 3) The distribution of hospitals in Korea showed that 61 cases(38.6%) were referred from Double Cross Clinic, 42 cases(26.6%) from health centers, 21 cases(13.3%) from tertiary referral hospitals, 15 cases(9.5%) from secondary referral hospitals, and 10 cases(6.3%) from primary care hospitals. The area distribution in Korea revealed that 98 cases(62%) were in Seoul, 17 cases(10.8%) in Gyeongsangbuk-do, 12 cases(7.6%) in Kyongki-do, 8 cases(5.1%) in Chungchongnam-do, each 5 cases(3.2%) in Gyeongsangnam-do and Chungchongbuk-do, 6 cases(3.8%) in other areas. 4) In the species of isolated mycobacteria other than tuberculosis, M. avium-intracellulare was found in 104 cases(65.2%), M. fortuitum in 20 cases(12.7%), M. chelonae in 15 cases(9.5%), M. gordonae in 7 cases(4.4%), M. terrae in 5 cases(3.2%), M. scrofulaceum in 3 cases(1.9%), M. kansasii and M. szulgai in each 2 cases(1.3%), and M. avium-intracellulare coexisting with M. terrae in 1 case(0.6%). 5) In pre-existing pulmonary diseases, pulmonary tuberculosis was 113 cases(71.5%), bronchiectasis 6 cases(3.8%), chronic bronchitis 10 cases(6.3%), and pulmonary fibrosis 6 cases(3.8%). The timing of diagnosis as having pulmonary tuberculosis was within 1 year in 7 cases(6.2%), 2~5 years ago in 32 cases(28.3%), 6~10 years ago in 29 cases(25.7%), 11~15 years ago in 16 cases(14.2%), 16~20 years ago in 15 cases (13.3%), and 20 years ago in 14 cases(12.4%). Duration of anti-tuberculous treatment was within 3 months in 6 cases(5.3%), 4~6 months in 17 cases(15%), 7~9 months in 16 cases(14.2%), 10~12 months in 11 cases(9.7%), 1~2 years in 21 cases(18.6%), and over 2 years in 8 cases(7.1%). The results of treatment were cure in 44 cases(27.9%) and failure in 25 cases(15.8%). 6) Associated extra-pulmonary diseases were chronic liver disease coexisting with chronic renal failure in 1 case(0.6%), diabetes mellitus in 9 cases(5.7%), cardiovascular diseases in 2 cases(1.3%), long-term therapy with steroid in 2 cases(1.3%) and chronic liver disease, chronic renal failure, colitis and pneumoconiosis in each 1 case(0.6%). 7) The clinical presentations of mycobacterial diseases other than tuberculosis were 86 cases (54.4%) of chronic pulmonary infections, 1 case(0.6%) of cervical or other site lymphadenitis, 3 cases(1.9%) of endobronchial tuberculosis, and 1 case(0.6%) of intestinal tuberculosis. 8) The symptoms of patients were cough(62%), sputum(61.4%), dyspnea(30.4%), hemoptysis or blood-tinged sputum(20.9%), weight loss(13.3%), fever(6.3%), and others(4.4%). 9) Smear negative with culture negative cases were 24 cases(15.2%) in first examination, 27 cases(17.1%) in second one, 22 cases(13.9%) in third one, and 17 cases(10.8%) in fourth one. Smear negative with culture positive cases were 59 cases(37.3%) in first examination, 36 cases (22.8%) in second one, 24 cases(15.2%) in third one, and 23 cases(14.6%) in fourth one. Smear positive with culture negative cases were 1 case(0.6%) in first examination, 4 cases(2.5%) in second one, 1 case (0.6%) in third one, and 2 cases(1.3%) in fourth one. Smear positive with culture positive cases were 48 cases(30.4%) in first examination, 34 cases(21.5%) in second one, 34 cases(21.5%) in third one, and 22 cases(13.9%) in fourth one. 10) The specimens isolated mycobacteria other than tuberculosis were sputum in 143 cases (90.5%), sputum and bronchial washing in 4 cases(2.5%), bronchial washing in 1 case(0.6%). 11) Drug resistance against all species of mycobacteria other than tuberculosis were that INH was 62%, EMB 55.7%, RMP 52.5%, PZA 34.8%, OFX 29.1%, SM 36.7%, KM 27.2%, TUM 24.1%, CS 23.4%, TH 34.2%, and PAS 44.9%. Drug resistance against M. avium-intracellulare were that INH was 62.5%, EMB 59.6%, RMP 51.9%, PZA 29.8%, OFX 33.7%, SM 30.8%, KM 20.2%, TUM 17.3%, CS 14.4%, TH 31.7%, and PAS 38.5%. Drug resistance against M. chelonae were that INH was 66.7%, EMB 66.7%, RMP 66.7%, PZA 40%, OFX 26.7%, SM 66.7%, KM 53.3%, TUM 53.3%, CS 60%, TH 53.3%, and PAS 66.7%. Drug resistance against M. fortuitum were that INH was 65%, EMB 55%, RMP 65%, PZA 50%, OFX 25%, SM 55%, KM 45%, TUM 55%, CS 65%, TH 45%, and PAS 60%. 12) The activities of disease on chest roentgenogram showed that no active disease was 7 cases(4.4%), mild 20 cases(12.7%), moderate 67 cases(42.4%), and severe 47 cases(29.8%). Cavities were found in 43 cases(27.2%) and pleurisy in 18 cases(11.4%). 13) Treatment of mycobacterial diseases other than tuberculosis was done in 129 cases(81.7%). In cases treated with the first line anti-tuberculous drugs, combination chemotherapy including INH and RMP was done in 86 cases(66.7%), INH or RMP in 30 cases(23.3%), and not including INH and RMP in 9 cases(7%). In 65 cases treated with the second line anti-tuberculous drugs, combination chemotherapy including below 2 drugs were in 2 cases(3.1%), 3 drugs in 15 cases(23.1%), 4 drugs in 20 cases(30.8%), 5 drugs in 9 cases(13.8%), and over 6 drugs in 19 cases (29.2%). The results of treatment were improvement in 36 cases(27.9%), no interval changes in 65 cases(50.4%), aggravation in 4 cases(3.1%), and death in 4 cases(3.1%). In improved 36 cases, 34 cases(94.4%) attained negative conversion of mycobacteria other than tuberculosis on cultures. The timing in attaining negative conversion on cultures was within 1 month in 2 cases(1.3%), within 3 months in 11 cases(7%), within 6 months in 14 eases(8.9%), within 1 year in 2 cases(1.3%) and over 1 year in 1 case(0.6%). Conclusion: Clinical, laboratory and radiological findings of mycobacterial diseases other than tuberculosis were summarized. This collected datas will assist in the more detection of mycobacterial diseases other than tuberculosis in Korea in near future.

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Studies on the Cold Resistance of The tea Plant in Korea -Especially on Leaf form and Cold resistance (한국산다수(韓國産茶樹)의 내한성(耐寒性)에 관(關)한 연구(研究) -특(特)히 지역별(地域別) 엽형태(葉形態)와 내한성(耐寒性)을 중심(中心)으로)

  • Kim, Jai Saing;Kim, Chang Ho
    • Journal of Korean Society of Forest Science
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    • v.53 no.1
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    • pp.37-43
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    • 1981
  • This study was aimed at expanding the tea plant culture in Korea to further north, and the leaf-form and the cold resistance of the tea plants selected form 7 districts(around Korea) were investigated. 1. The length of tea leaf is 5.1cm to 8.4cm, the width of the leaf is 2.3cm to 3.6cm, but the area of tea leaf in Mt. Mudung is $26.88cm^2$ and that is the widest of all. 2. The tooth number of the tea leaf in 43 to 73 but the number of Mt. Borim is remarkably number of all. The tooth number is increased or decreased in proportion to the leaf width and to the leaf length. 3. The lateral vein number is generally 13 to 19. The vein number of Mt. Borim is especially number of all. That is also increased or decreased in proportion to the leaf width and to the leaf length. 4. In general, the number of leaf formation index is 2 to 3, and ablong. 5. In general, those which come upper lands are remarkably small in length and width of the tea leaf and those which come from level lands are large. 6. All kinds of tea plant which is growing in Korea, area, are the same as those imported from China : Thea sinensis Linne var. Bohea. 7. I supposed that the external form of tea plant has a little changed by geography or climate for many a long day, since the tea plant had been transplanted in Mt. Samsin. 8. In the treatment of low temperature and duration of vernalization of their plants, those selected from Mt. Mudung and Mt. Hwaun were the coldest resistance, those from Mt. Samsin and Mt. Borim were medium and those from Mt. Joge and Nursery were cold sensitive. 9. The critical temperature of the tea plant from Mt. Mudung, Mt, Hwaum, Mt, Samsin and Mt. Borim was about $-10^{\circ}C$, and that from Mt. Joga and Nursery was about $-5^{\circ}C$. The critical temperature of frost injury of all tea plants in this experiments was $-15^{\circ}C$. 10. In spite of increasing the vernalization time, the critical temperature was not effected, but the treatments over critical temperature were increased their frost injuries. Based on these results, the coldest resistance, Mt. Mudung tea plant, was considered expanding their culture to further north improvement yields of the tea plants in Korea.

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Adsorption of Arsenic onto Two-Line Ferrihydrite (비소의 Two-Line Ferrihydrite에 대한 흡착반응)

  • Jung, Young-Il;Lee, Woo-Chun;Cho, Hyen-Goo;Yun, Seong-Taek;Kim, Soon-Oh
    • Journal of the Mineralogical Society of Korea
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    • v.21 no.3
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    • pp.227-237
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    • 2008
  • Arsenic has recently become of the most serious environmental concerns, and the worldwide regulation of arsenic fur drinking water has been reinforced. Arsenic contaminated groundwater and soil have been frequently revealed as well, and arsenic contamination and its treatment and measures have been domestically raised as one of the most important environmental issues. Arsenic behavior in geo-environment is principally affected by oxides and clay minerals, and particularly iron (oxy)hydroxides have been well known to be most effective in controlling arsenic. Among a number of iron (oxy)hydroxides, for this reason, 2-line ferrihydrite was selected in this study to investigate its effect on arsenic behavior. Adsorption of 2-line ferrihydrite was characterized and compared between As(III) and As(V) which are known to be the most ubiquitous species among arsenic forms in natural environment. Two-line ferrihydrite synthesized in the lab as the adsorbent of arsenic had $10\sim200$ nm for diameter, $247m^{2}/g$ for specific surface area, and 8.2 for pH of zero charge, and those representative properties of 2-line ferrihydrite appeared to be greatly suitable to be used as adsorbent of arsenic. The experimental results on equilibrium adsorption indicate that As(III) showed much stronger adsorption affinity onto 2-line ferrihydrite than As(V). In addition, the maximum adsorptions of As(III) and As(V) were observed at pH 7.0 and 2.0, respectively. In particular, the adsorption of As(III) did not show any difference between pH conditions, except for pH 12.2. On the contrary, the As(V) adsorption was remarkably decreased with increase in pH. The results obtained from the detailed experiments investigating pH effect on arsenic adsorption show that As(III) adsorption increased up to pH 8.0 and dramatically decreased above pH 9.2. In case of As(V), its adsorption steadily decreased with increase in pH. The reason the adsorption characteristics became totally different depending on arsenic species is attributed to the fact that chemical speciation of arsenic and surface charge of 2-line ferrihydrite are significantly affected by pH, and it is speculated that those composite phenomena cause the difference in adsorption between As(III) and As(V). From the view point of adsorption kinetics, adsorption of arsenic species onto 2-line ferrihydrite was investigated to be mostly completed within the duration of 2 hours. Among the kinetic models proposed so for, power function and elovich model were evaluated to be the most suitable ones which can simulate adsorption kinetics of two kinds of arsenic species onto 2-line ferrihydrite.

Steroid Effect on the Brain Protection During OPen Heart Surgery Using Hypothermic Circulatory Arrest in the Rabbit Cardiopulmonary bypass Model (저체온순환정지법을 이용한 개심술시 스테로이드의 뇌보호 효과 - 토끼를 이용한 심폐바이패스 실험모델에서 -)

  • Kim, Won-Gon;Lim, Cheong;Moon, Hyun-Jong;Chun, Eui-Kyung;Chi, Je-Geun;Won, Tae-Hee;Lee, Young-Tak;Chee, Hyun-Keun;Kim, Jun-Woo
    • Journal of Chest Surgery
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    • v.30 no.5
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    • pp.471-478
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    • 1997
  • Introduction: The use of rabbits as a cardiopulmonary bypass(CPB) animal model is extremely dif%cult mainly due to technical problems. On the other hand, deep hypothermic circulatory arrest(CA) is used to facilitate surgical repair in a variety of cardiac diseases. Although steroids are generally known to be effective in the treatment of cerebral edema, the protective effects of steroids on the brain during CA are not conclusively established. Objectives of this study are twofold: the establishment of CPB technique in rabbits and the evaluation of preventive effect of steroid on the development of brain edema during CA. Material '||'&'||' Methods: Fifteen New Zealan white rabbits(average body weight 3.5kg) were divided into three experimental groups; control CA group(n=5), CA with Trendelenberg position group(n=5), and CA with Trendelenberg position + steroid(methylprednisolone 30 mglkg) administration group(n=5). After anesthetic induction and tracheostomy, a median sternotomy was performed. An aortic cannula(3.3mm) and a venous ncannula(14 Fr) were inserted, respectively in the ascending aorta and the right atrium. The CPB circuit consisted of a roller pump and a bubble oxygenator. Priming volume of the circuit was approximately 450m1 with 120" 150ml of blood. CPB was initiated at a flow rate of 80~85ml/kg/min, Ten min after the start of CPB, CA was established with duration of 40min at $20^{\circ}C$ of rectal temperature. After CA, CPB was restarted with 20min period of rewarming. Ten min after weaning, the animal was sacrif;cod. One-to-2g portions of the following tissues were rapidly d:ssected and water contents were examined and compared among gr ups: brain, cervical spinal cord, kidney, duodenum, lung, heart, liver, spleen, pancreas. stomach. Statistical significances were analyzed by Kruskal-Wallis nonparametric test. Results: CPB with CA was successfully performed in all cases. Flow rate of 60-100 mlfkgfmin was able to be maintained throughout CPB. During CPB, no significant metabolic acidosis was detected and aortic pressure ranged between 35-55 mmHg. After weaning from CPB, all hearts resumed normal beating spontaneously. There were no statistically significant differences in the water contents of tissues including brain among the three experimental groups. Conclusion: These results indicate (1) CPB can be reliably administered in rabbits if proper technique is used, (2) the effect of steroid on the protection of brain edema related to Trendelenburg position during CA is not established within the scope of this experiment.

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