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Effects of Artificial Acid Rain on Seed Germination, Radicle Growth and Seedling Growth of Several Woody Species (인공산성우(人工酸性雨)가 몇 수종(樹種)의 종자발아(種子發芽), 유근생장(幼根生長) 및 묘목생장(苗木生長)에 미치는 영향(影響))

  • Kim, Gab-Tae
    • Journal of Korean Society of Forest Science
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    • v.81 no.1
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    • pp.30-39
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    • 1992
  • Artificial acid rain(pH2.0, 3.0, 4.0 and 5.0) was treated on the seeded pots of 4 species to examine its effects on germination, leaf injury and seedling growth. Aluminum ammonium sulfate solution (0.5, 1.0 and 2.5mM) and artificial acid rain (pH3.0, 4.0 and 5.0) were treated on the seeded germinators of 3 species to examine its effects on germination and radicle growth. Artificial acid rain was prepared by diluting sulfuric acid with ground water and ground water(pH6.5) was used as control. Artificial acid rain was sprayed to seeded pots three times per week. About 5mm of artificial acid rain was treated each time from early April to early October, 1991. Germination, seedling establishment, radicle growth, leaf injury and seedling growth were measured and compared among the treatments. The results were summarized as follows 1. Germination, seedling establishment rate of Pinus densiflora were highest on the pH5.0 pot whereas those of Ailanthus altissima was highest on the control pot, and those of Magnolia sieboldii showed the highest value on the pH3.0 pot. 2. The differences in seedling height of Pinus densiflora and Pinus rigida were significant among the treatment levels of acid rain, whereas those of Magnolia sieboldii and Ailanthus altissima were not significant. Seedling heights of Pinus densiflora and Pinus rigida were highest on the pH3.0 pot, and that of Magnolia sieboldii was highest on the pH4.0 pot, and that of Ailanthus altissima was highest on the control pot. 3. Seedling dry weights of Pinus densiflora. Pinus rigida, and Ailanthus altissima differed significantly among the treatments, but that of Magnolia sieboldii did not differ. Highest seedling dry weights of Magnolia sieboldii and Ailanthus altissima were observed on the pH4.0 pot, and that of Pinus densiflora was observed on the pH3.0 pot, and that of Pinus rigida was observed on the pH5.0 pot. 4. With decrease of pH value of artificial acid rain, the number of injured needle and injured individual tended to be increased. 5. The differences in effects of soil acidity were highly significant among the treatments for all species. 6. Radicle growth of Pinus densiflora differed significantly among pH levels and aluminum concentrations.

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Effects of a traditional Chinese medicine formula and its extraction on muscle fiber characteristics in finishing pigs, porcine cell proliferation and isoforms of myosin heavy chain gene expression in myocytes

  • Yu, Qin Ping;Feng, Ding Yuan;He, Xiao Jun;Wu, Fan;Xia, Min Hao;Dong, Tao;Liu, Yi Hua;Tan, Hui Ze;Zou, Shi Geng;Zheng, Tao;Ou, Xian Hua;Zuo, Jian Jun
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.11
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    • pp.1620-1632
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    • 2017
  • Objective: This study evaluated the effects of a traditional Chinese medicine formula (TCMF) on muscle fiber characteristics in finishing pigs and the effects of the formula's extract (distilled water, ethyl acetate and petroleum ether extraction) on porcine cell proliferation and isoforms of myosin heavy chain (MyHC) gene expression in myocytes. Methods: In a completely randomized design, ninety pigs were assigned to three diets with five replications per treatment and six pigs per pen. The diets included the basal diet (control group), TCMF1 (basal diet+2.5 g/kg TCMF) and TCMF2 (basal diet+5 g/kg TCMF). The psoas major muscle was obtained from pigs at the end of the experiment. Muscle fiber characteristics in the psoas major muscle were analyzed using myosin ATPase staining. Cell proliferation was measured using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) dye and cytometry. Isoforms of MyHC gene expression were detected by real-time quantitative polymerase chain reaction. Results: The final body weight and carcass weight of finishing pigs were increased by TCMF1 (p<0.05), while the psoas major muscle cross-sectional area was increased by TCMF (p<0.05). The cross-sectional area and diameter of psoas major muscle fiber Ι, IIA, and IIB were increased by TCMF2 (p<0.05). The cross-sectional area and fiber diameter of psoas major muscle fiber IIA and IIB were increased by diet supplementation with TCMF1 (p<0.05). Psoas major muscle fiber IIA and IIB fiber density from the pigs fed the TCMF1 diet and the type IIB fiber density from the pigs fed the TCMF2 diet were lower compared to pigs fed the control diet (p<0.05). Pigs fed TCMF2 had a higher composition of type Ι fiber and a lower percentage of type IIB fiber in the psoas major muscle (p<0.05). The expression levels of MyHC Ι, MyHC IIa, and MyHC IIx mRNA increased and the amount of MyHC IIb mRNA decreased in the psoas major muscle from TCMF2, whereas MyHC Ι and MyHC IIx mRNA increased in the psoas major muscle from TCMF1 (p<0.05). Peroxisome proliferator-activated receptor ${\gamma}$ $coactivator-1{\alpha}$ and CaN mRNA expression in the psoas major muscle were up-regulated by TCMF (p<0.05). Porcine skeletal muscle satellite cell proliferation was promoted by $4{\mu}g/mL$ and $20{\mu}g/mL$ TCMF water extraction (p<0.05). Both $1{\mu}g/mL$ and $5{\mu}g/mL$ of TCMF water extraction increased MyHC IIa, MyHC IIb, and MyHC IIx mRNA expression in porcine myocytes (p<0.05), while MyHC Ι mRNA expression in porcine myocytes was decreased by $5{\mu}g/mL$ TCMF water extraction (p<0.05). Porcine myocyte MyHC Ι and MyHC IIx mRNA expression were increased, and MyHC IIa and MyHC IIb mRNA expression were down-regulated by $5{\mu}g/mL$ TCMF ethyl acetate extraction (p<0.05). MyHC Ι and MyHC IIa mRNA expression in porcine myocytes were increased, and the MyHC IIb mRNA expression was decreased by $1{\mu}g/mL$ TCMF ethyl acetate extraction (p<0.05). Four isoforms of MyHC mRNA expression in porcine myocytes were reduced by $5{\mu}g/mL$ TCMF petroleum ether extraction (p<0.05). MyHC IIa mRNA expression in porcine myocytes increased and MyHC IIb mRNA expression decreased by $1{\mu}g/mL$ in a TCMF petroleum ether extraction (p<0.05). Conclusion: These results indicated that TCMF amplified the psoas major muscle cross-sectional area through changing muscle fiber characteristics in finishing pigs. This effect was confirmed as TCMF extraction promoted porcine cell proliferation and affected isoforms of MyHC gene expression in myocytes.

The E-mail Survey on the Neck Pain for Acupuncture and Moxibustion Clinical Guideline (경항통에 관한 침구임상 진료지침 개발을 위한 전자우편 설문조사)

  • Kim, Hyun-Wook;Kim, Sung-Soo;Nam, Dong-Woo;Kim, Eun-Jung;Hong, Kwon-Eui;Kim, Sung-Chul;Kim, Sun-Woong;Lee, Jae-Dong;Kim, Kap-Sung;Lee, Geon-Mok
    • Journal of Acupuncture Research
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    • v.26 no.3
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    • pp.67-80
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    • 2009
  • Objectives : The purpose of this survey is the development on the neck pain for acupuncture and moxibustion clinical guideline. Methods : The survey questionnaire was developed by the committee of experts who major in acupuncture & moxibustion or statistics for acupuncture clinical trial protocol development. The questionnaires were distributed via e-mail to 75 members of Korean Acupuncture & moxibustion society. 57 members completed answers, and the computerized data were analyzed by SPSS 17.0 statistical program. Results and Conclusions : 1. The first selected pattern identification on the neck pain This study shows that the meridian pattern identification was selected 35 times(61.4%), the pattern identification based on cause of disease was selected 8 times(14.0%), the visceral pattern identification was selected 7 times(12.3%), the other pattern identification was selected 4 times(7.0%), Qi blood yin yang pattern identification was selected 2 times(3.5%), according to symptoms was selected 1 time(2.4%). 2. Meridian pattern identification Small intestine meridian of hand Taeyang was used 39 times(18.1%), Large intestine meridian of hand Yangmyeong and Bladder meridian of foot Taeyang was used 34 times(15.7%), Gall-bladder meridian of foot Soyang was 32 times(14.8%), Tripple energizer meridian of hand Soyang was used 31 times(14.4%), Governor meridian was used 30 times(13.9%), Lung meridian of hand Taeeum was used 8 times(3.7%), Heart meridian of hand Soeum and Pericarduim meridian of hand Gworeum was used 4 times(1.9%). 3. Pattern identification based on cause of disease Wind-Cold-Dampness was used 31 times(17.5%), Accumulation of the collateral by Phelgm-Dampness was used 16 times(14.0%), affection by exopathogen Wind-Cold(stiff neck, sprain of cervical) was used 13 times (11.4%), Defecient-Cold was used 10 times(8.8%), affection by exopathogen Wind-Dampness was used 9 times(7.9%), Deep Invasion by Wind-Cold was used 8 times(7.0%), Wind-Cold was used 7 times (6.1%), Wind-Cold was used 6 times(5.3%), Accumulation in the Center by Phelgm-Dampness, Imparement of bou fluid by Pathogenic Heat, Wind-Heat with Dampness was used 5 times(4.4%), affection by exopathogen Wind-Dampness and Accumulation of the collateral by Wind-Cold was used 4 times(3.5%), Invasion of Dampness-Heat was used 2 times(1.8%). 4. Visceral pattern identification Rising of the Liver yang was used 16 times(41%), Yin deficiency of Liver and Kidney+pathogens was used 15 times(38.5%), Yin deficiency of Liver and Kidney was used 8 times(20.5%) on this survey.

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Exploration of optimum conditions for production of saccharogenic mixed grain beverages and assessment of anti-diabetic activity (잡곡당화음료 제조 최적 조건 탐색 및 항당뇨 활성 평가)

  • Lee, Jae Sung;Kang, Yun Hwan;Kim, Kyoung Kon;Yun, Yeong Kyeong;Lim, Jun Gu;Kim, Tae Woo;Kim, Dae Jung;Won, Sang Yeon;Bae, Moo Hoan;Choi, Han Seok;Choe, Myeon
    • Journal of Nutrition and Health
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    • v.47 no.1
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    • pp.12-22
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    • 2014
  • Purpose: This study was conducted to establish the production conditions through optimization of the production process of beverages using Aspergillus oryzae CF1001, and to analyze volatile compounds and antidiabetic activity. Methods: The optimum condition was selected using the response surface methodology (RSM), through a regression analysis with the following independent variables gelatinization temperature (GT, $X_1$), saccharogenic time (ST, $X_2$), and dependent variable; ${\Delta}E$ value (y). The condition with the lowest ${\Delta}E$ value occurred with combined 45 min ST and $50^{\circ}C$ GT. The volatile compounds were analyzed quantitatively by GC-MS. Results: Assessment of antidiabetic activity of saccharogenic mixed grain beverage (SMGB) was determined by measurement of ${\alpha}$-glucosidase inhibition activity, and glucose uptake activity and glucose metabolic protein expression by reverse transcriptase polymerase chain reaction (RT-PCR) and western blot analysis. Results of volatile compounds analysis, 62 kinds of volatile compounds were detected in SMGB. Palmitic acid (9.534% ratio), benzaldehyde (8.948% ratio), benzyl ethyl ether (8.792% ratio), ethyl alcohol (8.35% ratio), and 2-amyl furan (4.826% ratio) were abundant in SMGB. We confirmed that ${\alpha}$-glucosidase inhibition activity, glucose uptake activity, and glucose-metabolic proteins were upregulated by SMGB treatment with concentration dependent manner. Conclusion: Saccharogenic mixed grain beverage (SMGB) showed potential antidiabetic activity. Further studies will be needed in order to improve the taste and functionality of SMGB.

Effects of Zardaverine in Freezing Extender on Kinetic Characteristics of Post-Thawed Boar Sperm (동결보존액에 Zardaverine의 첨가가 동결-융해 후 돼지 정자의 운동학적 특성에 미치는 영향)

  • Kim, Jeong A;Cho, Eun Seok;Jeong, Yong Dae;Choi, Yo Han;Hong, Jun Ki;Kim, Young Sin;Chung, Hak Jae;Baek, Sun Young;Sa, Soo Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.9
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    • pp.251-258
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    • 2020
  • This study investigated the effect of Zardaverine supplementation in freezing extender, on kinetic characteristics of post-thawed boar sperm. Cryopreservation of boar sperm is an important technique of assisted reproductive technology and genetic resource banking. Although this technique is particularly useful, freeze-thaw cycles associated with sperm cryopreservation significantly reduce sperm quality. Semen from mature Duroc boars were collected and cryopreserved in freezing extenders (LEY) treated with varying concentrations of Zardaverine (0, 20, 50, 75, 100 𝜇M). The time-dependent kinetic characteristics of post-thawed spermatozoa were determined after thawing by applying computer-assisted sperm analysis (CASA). We observed that the motility immediately after thawing was significantly higher in 20 𝜇M stocks than in control (0 𝜇M) and the other treatments (p<0.05). Curvilinear velocity (VCL) in 0 𝜇M and 20 𝜇M stocks were significantly higher than the other treatment groups, except 75 𝜇M (p<0.05). Higher average path velocity (VAP) was obtained at 20 𝜇M as compared to 100 𝜇M, whereas amplitude of head lateral displacement (ALH) was significantly higher at 20 𝜇M than 50 𝜇M and 100 𝜇M (p<0.05). No differences were obtained for Straight-line velocity (VSL) and Linearity (LIN). In conclusion, our results indicate that Zardaverine improves the motility, VCL, VAP, and ALH of post-thawed boar sperm.

Relationship between Admission and Clinical Features of Children Who Visited the Emergency Department with Seizures (경련을 주소로 응급실을 방문한 아이의 임상양상과 입원과의 관계)

  • Yoon, Sung Kwan;Kim, Eun Young;Yang, Eun Seok;Moon, Kyung Rye;Park, Sang Kee;Park, Young Bong;Rho, Young Il;Cho, Soo Hyeong
    • Clinical and Experimental Pediatrics
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    • v.46 no.10
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    • pp.1003-1007
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    • 2003
  • Purpose : To review the seizure-related complaints and analyze the relationship between admission rates and clinical features in children who had visited the emergency department with seizures. Methods : Retrospectively, we reviewed 180 patients(male 100, female 80) suffering from seizures, who had visited to the emergency department of Chosun University Hospital from January 2000 to June 2002. We have analyzed the correlation between admission rate and clinical features such as age, seizure type, seizure duration and individual laboratory findings(CT or MRI, and CSF). Results : Out of 4,865 total children who visited the emergency department, 180 patients(3.7%) were seizure related. The most common seizure type was simple febrile seizure(52.2%). The admission rate of children with seizures was 48.9%. The admission rate according to age, sex and abnormal laboratory findings revealed no significant correlations(P>0.05). There was a significant correlation between admission and both status epilepticus 82.4%(14/17) and complex febrile seizure 63.6%(14/22) (P<0.05). According to the duration of convulsions, admission rates were 41.2% when within five minutes, 60% when six-15 minutes, 58.8% when 16-30 minutes, 85.7% when 30 minutes, to one hour and 66.7% when above one hour of duration. According to the seizure frequency, admission rates of recurrent seizure patients(61.4%=43/70) was higher compared to the first time seizure patients(40.9%=45/110). Conclusion : We found that the admission rate of children visiting the emergency department for seizure treatment was 48.9% and significantly correlated with duration, type and frequency of seizure.

The Survey for Improvement in Clinical Practice Curriculum of Physiotherapy (물리치료 임상실습 교과내용 개선을 위한 조사연구)

  • Jang, Su-Gyeong
    • Journal of Korean Physical Therapy Science
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    • v.5 no.3
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    • pp.659-674
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    • 1998
  • This Study was to investigate elaborated research themes and direction through specifying the problems of clinical practice education and looking for the direction of improvement. It was in the basis of the viewpoint of the educators that professors and therapists who were the subjects of this study. Perform this study, the 15 colleges' professors and the 55 hospitals' therapists was made up questionnaire, and the data was analysing by Chi-square test and percentage. The results were as follow : ${\cdot}$ In a personal history among the general qualities, professors have little clinical practice history(l-5 years, 53.3%), and therapists have little lecture career(1-5 years, 43.6%, have no 49.0%), ${\cdot}$ The 78.6% subjects were unsatisfied of clinical practice systems. ${\cdot}$ The correlation between clinical history, school career and lecture career and the satisfaction level of clinical practice systems has no(P<.005), ${\cdot}$ The subjects were agreed to that clinical practice curriculum should be changed(67.1%), reinforced(82.9%), and specified(90.0%). ${\cdot}$ The clinical practice credits are 11 points averagely. ${\cdot}$ In the clinical practice curriculum, it made no difference in the practicum of diseases, modality, and the therapeutic techniques between professors and therapists. ${\cdot}$ The 100% professors said that the practicum of the patients' assessment is necessary, and the 63.6% therapists were training for that. ${\cdot}$ The 66.7% professors said that the practicum of the clinical psychology is necessary, and only the 20.0% therapists were training for that. ${\cdot}$ The 93.3% professors said that the practicum of the patients' management is necessary, and the 50.9% therapists were training for that. ${\cdot}$ The 66.7% professors said that the practicum of the medical ethics is necessary, and the 34.5% therapists were training for that. ${\cdot}$ The 46.7% professors said that the practicum of the hospital administration is necessary, but the 54.5% therapists have not training. ${\cdot}$ The 33.3% professors said that the practicum of the pharmacology is necessary, but the 81.8% therapists have not training. ${\cdot}$ The 86.7% professors said that the practicum of the patient's education is necessary, and the 43.6% therapists have training. ${\cdot}$ The 66.7% professors said that the practicum of the prosthesis and brace is necessary, but the 14.5% therapists have not training. ${\cdot}$ The 60.0% professors said that the practicum of the exercise prescription is necessary, but the 25.5% therapists have not training. ${\cdot}$ The 53.5% professors said that the practicum of the emergency treatment is necessary, but the 52.7% therapists have not training. ${\cdot}$ Drawing up the plan about the curriculum of clinical practice, the professors (46.7%) were agreed to national master plan framing by an expert advisor, but the therapists (58.2%) said that the plan that make the most of hospitals' characteristics should be specified. ${\cdot}$ It was found that a clinical special therapists(54.5%) was good as a person in charge of clinical practice education, in that each therapist's own good time (34.5%) was. ${\cdot}$ It made use of the form framing by college(40.0%) as the clinical practice textbook, the form framing by hospital (42.9%) and each therapist(22.9%) as the plan, and the form framing by college (74.3%) as the measurement. ${\cdot}$ The most difficult point in clinical practice education was the lacks of the theory-praciticum linkage(78.2%). ${\cdot}$ It was found that the period of clinical practice was in the second semester-third grade (40.0%) and the desirable period was in the first semester-third grade(50.0%). ${\cdot}$ Professors (53.3%) were agreed that the desirable clinical practice duration was from four months to six months(60.0%), and the therapists (60.0%) were agreed that from one month to three months. ${\cdot}$ This study presented the lacks of rearing the experts, the lacks of cultural education, and the lacks of the theory-clinical practice linkage. There were need to develop the systematic programs, clinical practice textbooks, the measurements and the special hospital for clinical practice. And it was need to reduce the gab between of the hospitals for clinical practice, to cut down the costs. and to improve the labour conditions of leaders. In view of this findings, it takes notice of that both professor and therapist were dissatisfied at the present clinical practice systems. These results point out the problems of clinical practice systems, and do not make expect to us the successive and positive clinical practice. The general, specific and intensive plan about the problems and the direction of improvement that establishing the level of hospital for clinical practice and physiotherapy can be elaborated.

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Analysis of CO2 Emission Intensity per Industry using the Input-Output Tables 2003 (산업연관표(2003년)를 활용한 산업별 CO2 배출 원단위 분석)

  • Park, Pil-Ju;Kim, Mann-Young;Yi, Il-Seuk
    • Environmental and Resource Economics Review
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    • v.18 no.2
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    • pp.279-309
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    • 2009
  • Greenhouse gas emissions should be precisely forecast to reduce the emissions from industrial production processes. This study calculated the direct and indirect $CO_2$ emission intensities of 401 industries using the Input-Output tables 2003 and statistical data on the amount of energy use. This study had some limitations in drawing study findings because overseas data were used given the lack of domestic data. Other limiting factors included the oil distribution problems in the oil refinery sector, re-review of carbon neutral, and insufficient consideration of waste treatment. Nonetheless, this study is very meaningful since the direct and indirect $CO_2$ emission intensities of 401 industries were calculated. Specifically, this study considered from the zero-waste perspective the effects of waste, which attract interest worldwide since coke gas and gas from the steel industry are obtained as byproducts for the first time in Korea. According to the results of the analysis of $CO_2$ emission intensity per industry, typical industries whose indirect $CO_2$ emission intensity is high include crude steel making, Remicon, steel wire rods & track rail, cast iron, and iron reinforcing rods & bar steel. These industries produce products using the raw materials produced in the industrial sector whose $CO_2$ emission intensity is high. The representative industries whose direct $CO_2$ emission intensity is high include cement, pig iron, lime & plaster products, andcoal-based compounds. These industries extract raw ore from nature and refine them into raw materials that are useful in other industries. The findings in this study can be effectively used for the following case: estimation of target $CO_2$ emission reduction level reflecting each industrial sector's characteristics, calculation of potential emission reduction of each policy to reduce $CO_2$ emissions, identification of a firm's $CO_2$ emission level, and setting of the target level of emission reduction. Moreover, the findings in this study can be utilized widely in fields such as System of integrated Environmental and Economic Accounting(SEEA) and Material Flow Analysis(MFA) as the current topic of research in Korea.

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Material Characteristics and Deterioration Assessment of the Stone Buddhas and Shrine in Unjusa Temple, Hwasun, Korea (화순 운주사 석조불감의 재질특성과 풍화훼손도 평가)

  • Park, Sung-Mi;Lee, Myeong-Seong;Choi, Seok-Won;Lee, Chan-Hee
    • Journal of Conservation Science
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    • v.24
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    • pp.23-36
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    • 2008
  • The stone Buddhas and Shrine of Unjusa temple (Korea Treasure No. 797) in Hwasun formed in Koryo Dynasty are unique style which the Buddha faces each other the back parts of south and north within the stone Shrine. The stone Buddhas and Shrine are highly evaluated in historical, artistic and academic respects. But, the stone properties have been exposed in the open system various aspects of degradations weathered for a long time without specific protective facilities. The rock materials of the stone Buddhas and Shrine are about 47 blocks, and total press load is about 56.6 metric ton. The host rocks composed mainly of white grey hyaline lithic tuff and rhyolitic tuff breccia. In addition, biotite granite used as part during the restoration works. The chemical index of alteration for host tuffaceous rocks and the replacement granites range from 52.1 to 59.4 and 50.0 to 51.0, respectively. Weathering types for the stone Buddhas and Shrine were largely divided with physical, chemical and biological weathering to make a synthetic deterioration map according to aspects of damage, and estimate share as compared with surface area. Whole deterioration degrees are represented that physical weathering appeared exfoliation. Chemical weathering is black coloration and biological weathering of grey lichen, which show each lighly deterioration degrees. According to deterioration degree by direction of stone Buddhas and Shrine, physical weathering mostly appeared by 39.1% on the sorthern part, and chemical weathering is 61.2% high share on the western part. Biological weathering showed 38.3% the largest distribution on the southern part. Therefore, it is necessary to try hardening for the parts with serious cracks or exfoliations, remove secondary contaminants and organisms through regular cleaning. Also necessary to make a plan to remove moisture of the ground which causes weathering, and estimate that need established and scientific processing through clinical demonstration of conservation plan that chooses suitable treatment.

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The effect of dexamethasone on the gene expression of the bone matrix protein in the periodontal ligament cells (치주인대세포의 골기질 단백질 유전자 발현에 대한 Dexamethasone의 영향)

  • Chung, Ha-Bong;Park, Jin-Woo;Suh, Jo-Young
    • Journal of Periodontal and Implant Science
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    • v.32 no.3
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    • pp.445-456
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    • 2002
  • The purpose of this study were to determine that dexamethasone(Dex) induces differentiation of periodontal ligament(PDL) cells to osteoblastic cells and to investigate expression of matrix Gla protein(MGP), which is one of bone matrix protein. The isolated human PDL cells and gingival fibroblasts were prepared and cultured. The fourth or sixth sub-passage cells were used in this experiments. control group, ascorbic acid and ${\beta}$-glycerophosphate treated group, ascorbic acid, ${\beta}$-glycerophosphate and l00nM Dex treated group, ascorbic acid, ${\beta}$-glycerophosphate, and 5 ${\mu}M$ Dex treated group were made for study. The results were as follows: Cellular morphological change of PDL cells according to time was investigated. At first, the cells exhibited confluent monolayer of spindle or polygonal appearance. The multilayer of cells were seen after 7 days of treatment. After 14 days, the cells lost polarity and were densely packed. The mineralized nodule formation was seen at 21 days in the only Dex treated PDL cell groups. In the gingival fibroblast groups and no Dex treated PDL cell groups, the mineralized nodule was not seen. The mineralized nodule formation of 5 ${\mu}M$ Dex treated group was higher than 100 nM Dex treated group. Alkaline phosphatase(ALP) activity was higher in the Dex treated PDL cell groups of 14 and 21 days than 0 and 7 days. MGP was expressed in the control and all experimental groups and the expression was constant at 0,7,14,21 day. The above results confirm that Dex is affected to differentiation of the PDL cells to osteoblastic or cementoblastic cells and has dose-dependent effect for mineralization. And, MGP is expressed in the PDL cells and is not affected to mineralization of PDL cells.