• Journal of the Korean Wood Science and Technology
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• v.27 no.1
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• pp.88-104
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• 1999

This study was carried out to classify the Hanjis into three groups that were indigenous Hanji, traditional Hanji, and improved Hanji handmade by paper making method according to the physical properties of each paper sheet such as tensile, bursting and tearing strength, folding endurance and fiber orientation in each layer. The results obtained were summarized as follows: 1. The multi-layered Hanjis made by "Oebal" Hanji making method in different direction of fiber orientation have good properties in tearing resistance. 2. The multi-layered Hanji in different direction of fiber orientation has good properties in the tearing resistance, but the burst index and the breaking length results were lower than the single layered Hanjis. 3. The different fiber orientation and multi-layered method didn't increase, the three indexes(burst index, tear index, breaking length). Only, the different direction of fiber orientation decreased the difference of width and length strength (tensile, tear) of the Hanji. 4. "Dochim"(Korean finishing touch process for indigenous Hanji by fulling round sticks) greatly increase folding endurance(double folds, not $log_{10}$) and good effect to tensile strength and burst strength. 5. The today's Oebal Hanji were the maximum of 2 layers and the indigenous Oebal Hanji were 16 layers the maximum. In addition, average of the indigenous Oebal Hanji was 4 layers(all 4-layer Hanji were the different fiber orientation of each layer). 6, The indigenous Hanji(multi-layered, and different fiber orientation) was good condition with "Dochim". Dochim increased tensile strength and burst strength of the indigenous Hanji. So the three-strength indexes were similar level("--"). 7. When the number of layer which were same fiber orientation increase, the increased Hanji became similar strength pattern("V", breaking length and burst index was higher than tear index) with "Ssangbal" Hanji. 8. The single layered papers that made by "Oebal" Hanji making method were similar strength pattern with Ssangbal Hanji. 9. There was no way to find the width and length direction of multi-layered Hanji by comparison between the difference of tensile strength and the difference of tearing resistance. 10. The compared pattern of tensile strength and tearing resistance of indigenous Oebal Hanji was different from today's Oebal Hanji. Especially, the tearing resistance of all indigenous Oebal Hanji(16 samples) was stronger on width of tearing resistance. And in the half of indigenous Oebal Hanji samples, the width of tensile strength and tearing resistance was stronger than length strength (Indigenous Oebal: '$\ulcorner\lrcorner$' 50%, '$\bigcup$' 50% $\leftrightarrow$ Today's Oebal: '$\ulcorner\lrcorner$' 12%, '$\bigcup$'6%, '$\llcorner\urcorner$'17%, '$\bigcap$'65%). In 65% today's Oebal, the length direction of tensile strength and tearing resistance was stronger than the width direction.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.1
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• pp.25-28
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• 2011

Purpose: The aim of study is to find accuracy of pocket dosimeter in measuring exposed dose in compared with survey meter and to compare exposed dose according as Nuclear medicine exams. Materials and Method: First, radiation dose to point source(185 MBq,370 MBq, ${\ldots}$, 1665 MBq, 1850 MBq) were measured in using a pocket dosimeter and a survey meter. Second, radiation dose to 12 patients injected $^{18}F$-FDG 370 MBq were measured in using a pocket dosimeter and a survey meter. Third, radiation dose to 10 patients injected $^{99m}Tc$-DPD 925 MBq were measured in using a pocket dosimeter and a surveymeter. Result: The average is $70.12{\pm}39.36{\mu}Sv/h$ in measurement of point source with Surveymeter and $5{\pm}3.06{\mu}Sv$ in measurement of point source with Pocket dosimeter. The average is $25.04{\pm}6.16{\mu}Sv/h$ in measurement of PET/CT patients with Surveymeter and $2.41{\pm}0.51{\mu}Sv$ in measurement of PET/CT with Pocket dosimeter. The average is $8.58{\pm}0.96{\mu}Sv/h$ in measurement of Bone Scan patients with Surveymeter and $1{\mu}Sv$ in measurement of Bone Scan patients with Pocket dosimeter. Significant difference found between Survey meter value and Pocket dosimeter value in all experimentation (p<0.001). Conclusion: Accoring to rusult Wearing Pocket dosimeter is usefulnee in manerage of exposed dose in nucler medicine exams.

• Journal of Sericultural and Entomological Science
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• no.12
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• pp.47-50
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• 1970

There are many factors affecting the development of sericultural industry in Korea. The setting of a rational pricing system for sericultural products is one of important activities of the Korean Government to improve the incentives to producers. The determination o： the prices for many years were based on the production costs including a certain level of profits. Some of cost items are in conflict both in cocoon producers and silk-reeling industries. Government officials have to evaluate these conflicting problems and estimate the consequences of their decisions. In this situation the final decision often became political decisions. This analysis is aimed at providing an alternative method of setting the prices of sericultural products. The criteria of the equilibrium employed in this analysis are based on economic principle which equilibrium condition is determined by the relationships between the marginal productivity of input factors and factor prices. In order to obtain the related information Cobb-Douglas'functions were fitted using KIST computer and data were obtained mostly from the Bank of Korea and the Ministry of Agriculture and Forestru, An important assumption is that "Opportunity Costs" of factors input in both cocoon production and silk-Peeling industries are same, The major finding s obtained are as followings. 1) The sum of coefficient of production elastisity in silk-reeling industries is greater than one. Silk-reeling industries are operating under the situation of increasing return to scale and it is, therefore, expected to develop the industries as the capital-intensive large scale. 2) The cocoon producing farmers are under the situations of the decreasing return to scale and it is expected to continue their cocoon farming as the labor-intensive small scale, assuming the present level of production technology. As the development of commercial farming, the resources input in cocoon production will be shifted to the production for higher profitable crops, 3) The price elastisity of production is higher in cocoon production than in silk-reeling industries. It is expected that the price changing effects on domestic production will be resulted from cocoon producers. 4) Based on analysis results of marginal productivities and the opportunity costs of resources, cocoon price for meeting equilibrium price condition is to be increased by 8-16 percent or standard price level of silk increased by 6-8 percent. There were the possibilities of over evaluation on opportunity cost of resources input in silk-reeling industries, or income transfered from the farmers to the industries. It is recommended that the prices for meeting equilibrium price conditions are to be determined by 72 percent for cocoon and 28 percent for silk-reeling costs, based on standard level of the exporting prices.

• The Korean Journal of Nuclear Medicine
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• v.27 no.1
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• pp.112-117
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• 1993

Background Radioiodine ($^{131}I$), a major component of nuclear fallout and a valuable therapeutic agent for thyrotoxicosis and thyroid cancer, has been regarded as a mutagen or a carcinogen without any convincing evidence. To evaluate the genotoxicity of radioiodine ($^{131}I$) we performed a micronuclei test in mice bone marrow. Materials and methods : Mice (ICR strain, $25{\sim}30 g$) were divided to 4 groups: control, group 1 (0.17 mCi/kg, usual therapeutic dose for thyrotoxicosis), group 2 (1.67 mCi/kg, usual therapeutic dose for thyroid cancer), and group 3 (16.67 mCi/kg, usual accumulated dose causing bone marrow suppression). $^{131}I$ was administered intraperitoneally. Ten mice of each group were sacrificed at days 1 and 3. Bone marrow were smeared and stained with May-Grunwald Giemsa method. One thou-sand polychromatic erythrocytes (PCE) and normochromatic erythrocytes (NCE) were counted under the light microscope, and the number of micronucleated PCEs were recorded. Results : The frequency of micronuclei in PCE (and NCE in parenthesis) in the control group was $0.25{\pm}0.07$ ($0.23{\pm}0.07$)% in day 1 and $0.24{\pm}0.07$ ($0.21{\pm}0.07$)% in day 3. Those in group 1 was $0.27{\pm}0.1$ ($0.23{\pm}0.09$)% in day 1 and $0.28{\pm}0.07$ ($0.25{\pm}0.06$)% in day 3. Micronuclei was noted in $0.29{\pm}0.08$ ($0.26{\pm}0.09$)% in day 1 and $0.31{\pm}0.05$ ($0.29{\pm}0.06$)% in day 3 in group 2, and in $0.32{\pm}0.06$ ($0.25{\pm}0.09$)% in day 1 and $0.33{\pm}0.08$ ($0.3{\pm}0.06$)% in day 3 in group 3. There was no difference in the frequency of micronuclei between each groups (p> 0.05). Conclusion : Radioiodine ($^{131}I$) did not cause any genotoxicity in mice bone marrow even at the large dose (16.67 mCi/kg).

• The Korean Journal of Nuclear Medicine
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• v.28 no.1
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• pp.85-88
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• 1994

근래 골조직에 있어서 자율신경의 기능에 대하여 많은 연구가 이루어지고 있으며, 골내의 자율신경의 해부학적 분포는 많이 알려져 있다. 그러나 임상적으로 반사적 교감신경 이상이나 레이노드 현상등과 같은 교감신경의 기능이상증에서나, 버거씨병 등의 치료 목적으로 시행되고 있는 교감신경 절제술 후, 자율신경기능의 변화가 사지골의 혈류나 골대사에 미치는 영향에 대하여는 아직도 논란의 여지가 있다. 저자들은 교감신경절제술 후 시간 경과에 따른 골에 미치는 영향을 알아보기 위하여 흰쥐에서 골대사와 혈류상태를 비교적 충실히 반영하는 정량적 골스캔을 시행하였다. 체중 $300{\sim}400g$의 수컷 흰쥐 10마리에서 복강을 통한 편측 요추부 교감신경절제술을 시행하였고, 수술 전과 후 1일, 3일, 1주, 2주, 3주, 4주에 양측 하지에서 각각 골스캔을 시행하고 교감신경 절제측 하지와 정상 하지에 대칭적으로 관심구역을 정하여 양측의 골스캔상 섭취계수를 비교하였다. 측정부위는 각 하지의 대퇴골간, 경골간 및 중족골로 하였다. 교감신경 절제술을 시행한 하지에서는 골스캔 소견상 수술 후 1일 또는 3일부터 동위원소 집적이 유의하게 증가되었으며 원위부로 갈수록 더욱 증가되었다. 그러나 3주 이후에는 정상측 수준으로 환원되었다. 교감신경절제술 후 골스캔상 동위원소집적이 증가되는 것은 골자체의 혈류가 증가되기 때문이며 이차적으로 골의 흡수를 유발하여 골밀도가 감소하는 것으로 생각되는데 이러한 변화는 시술 후 1일 째부터 관찰되어 사지골이 교감신경 절제에 매우 민감하게 반응하는 것을 알 수 있었다.9m}Tc$-MAA를 이용한 간 동맥 혈류 검사는 간암에서 색전술의 효과를 정확히 평가할 수 있는 유용한 검사법으로 이용될 수 있으리라 생각한다. 활성화 과정을 알아볼 수 있었으며 위상영상히스토그램을 통하여 이를 정량화하여 심실내 전기적 활성의 비동시성 여부를 추적관찰 할 수 있는 비관혈적검사임을 확인하였다.며, 3. $^{99m}Tc$으로 표지된 avidin과 streptavidin은 먼저 간으로 흡수된 후 대사된 다음 신장으로 배설된다는 사실을 알았다.damole에 의한 부작용은 흉통, 두통, 복통 등의 순이었고 전예에서 호전되었으며 생명에 위험을 초래할 수 있는 정도의 심장마비나 심부정맥은 한 예에서도 없었다. 결론적으로 dipyridamole은 약물부하 심근 SPECT 검사에 안전하게 사용할 수 있는 약물로 사료된다. 미소핵 빈도수가 증가하는 경향을 보였으나, 각 군간에 통계학적으로 유의한 차이는 없었다(p>0.05). 결론 : 임상적으로 치료를 중단하게 되는 1000mCi/60 Kg(16.67 mCi/Kg)를 투여한 군에서도 생쥐 골수내 미소핵이 발현되지 않는 것으로 보아, 방사성옥소는 비교적 안심하고 치료에 사용할 수 있는 제제로 사료되었다.반드시 비례하지만은 않아서 시간경과에 따른 추후 검사가 필요하리라 생각된다. 또한 방광요관역류가 있는 환아에서 DMSA 섭취율로 신기능을 평가할 때, 특히 영유아에서 연령에 따른 고려가 있어야 할 것으로 보인다.었다. 4) $^{99m}Tc-DISIDA$ hepatobiliary scintigram 음성율을

• Korean Journal of Medicinal Crop Science
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• v.9 no.2
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• pp.99-107
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• 2001

Germination of Codonopsis pilosula seeds and afterward their seedling emergence have been occasionally very poor due to their dormancy and structural defects. The study was done to determine the treatment effects of priming, $GA_3$, agitation and washing during and after priming, drying and water imbibition after drying on germination of its seeds and then of the successive three combined treatment after priming on the its seedling emergence to model its presown seed treatment. While agitation at the speed of 10 rpm was made or not, priming using $Ca(NO_3)_2$ and $GA_3$ under their different concentrations and light quality illuminated for 12 hours a day were done separately. Then their two best results were compared to determine the better one. Using the above determined best result, washing was done 3 minutes in the tap water or not, and drying of washed seeds was made under 4 different lights, and water imbibition of the dried seeds with differed period were successively done to deduce its presown seed treatment. In the comparison of the best germination rate of priming and $GA_3$, the former showed considerably higher rate than the latter; the priming treatment was done at agitated $Ca(NO_3)_2$ 150 mM solution under darkness or 12 hour red light illumination a day for 2 days. Washing after priming enhanced the rate compared to no-washing. Drying was the best way at which seeds washed were desiccated under $35^{\circ}C$ and 4 hour red light illumination. Water imbibition immediately before sowing must be made for 2 days. Seedling emergence rate was the highest at the seeds from successive 4 treatments, priming, washing, drying and water imbibition before sowing of two others, the priming and washing, or the priming, washing and water imbibition, meaning that its presown seed treatment must follow the procedure of the above 4 successive ones.

• Journal of Chest Surgery
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• v.40 no.3 s.272
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• pp.200-208
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• 2007

Background: The effect of patient-prosthesis mismatch (PPM) on the clinical outcome following aortic valve replacement (AVR) remains controversial. This study compared the surgical outcomes of AVR between patients with a patient-prosthesis mismatch and those having undergone an aortic annular enlargement. Material and Method: Six hundred and twenty seven adult patients, who underwent AVR with stented bioprosthetic or mechanical valves, between January 1996 and February 2006, were evaluated. PPM was defined as an indexed effective orifice area (iEOA) ${\leq}0.85cm^2/m^2$, and Severe if the iEOA${\leq}0.65cm^2/m^2$ PPM was present in 103 (16.4%, PPM group) patients, and severe in 11 (1.8%, SPPM group). During the period of the study, 21 patients underwent an AVR with annular enlargement (AE group). Result: The mean iEOA of the AE group was larger than that of the PPM group ($0.95\;vs.\;0.76cm^2/m^2,\;p=0.00$). The AE group had longer CPB, ACC and operation times than the PPM group, and showed a tendency toward higher operative mortality (14.3% vs. 2.9%, p=0.06). The SPPM group had higher AV pressure gradients (peak/mean) than the AE group (72/45 mmHg vs. 38/25 mmHg, p=0.02/0.06) and suffered more AV related events (AV reoperation or severe aortic stenosis)(45.5% vs. 9.5%, p=0.03). LV masses were not regressed in the patients who experienced an AV related event. Conclusion: During AVR in patients with a small aortic annulus, annular enlargement should be carefully applied taking into account the high risk of operative mortality due to annular enlargement and co-morbidities of patients. Aortic annular enlargement; however, should be considered as an alternative method in patients expected to have a severe PPM after an AVR.

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.79-95
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• 2017

Euiam and Paldang Reservoirs have often been facing water quality problems, such as eutrophication, algal blooms and off-flavors by treated wastewater effluent (TWE) in the North-Han and the Han River basins, but little is examined on the direct biological effect of TWE. This study tested algal growth potential (AGP) of four TWEs discharged into Euiam and Paldang Reservoirs to evaluate water fertility in September 2014 and March and September 2015. Test alga was used Anabaena circinalis isolated from Paldang Reservoir. Mean concentration of T-N and T-P in TWEs was $3,956.7{\mu}g\;N\;L^{-1}$ and $50.8{\mu}g\;P\;L^{-1}$, and the proportion of $NO_3-N$ and $PO_4-P$ to the total fraction was 72.1% and 40.8%, respectively. Both N and P were high in TWEs, but much higher N than P concentration indicates strong P-limitation. As a consequence, the maximum AGP was determined by $PO_4-P$ concentration (r=0.998, p<0.01). Mean AGP value was $15.4mg\;dw\;L^{-1}$ among four effluents indicating its eutrophic condition. Due to the establishment of tertiary (advanced T-P) treatment method in the studied plants recently, P concentration was significantly decreased in TWEs compared to the years prior to 2012. However, P concentration seems to be still high enough to cause eutrophication and algal blooms. Therefore, wastewater treatment to P-free level needs to be considered if effluents are directly discharged into the drinking water resources.

• Korean Journal of Ecology and Environment
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• v.50 no.1
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• pp.137-147
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• 2017

The identity of toxin producers remains only hypothesis unless there were identified by strain isolation and analytical confirmation of both the cyanotoxin production and the genetic identity of the monoculture. The purposes of this study were to identify a morphologic and phylogenetic classification in Aphanizomenon flos-aquae strains isolated from the Nakdong River and to investigate the potential ability of the strains to produce toxins such as saxitoxin and cylindrospermopsin using target genes. The 16S rRNA and sxtA, sxtI, cyrA, cyrJ genes were analyzed on two strains (DGUC001, DGUC003) isolated from the Nakdong River. Morphological features of the strains were observed a shape of aggregated trichomes in parallel fascicles which can reach up to macroscopic size and a hyaline terminal cell without aerotope. In addition, the 16S rRNA phylogenetic analyses showed that the strains were identified as the same species with high genetic similarity of 98.4% and grouped within a monospecific andsupported cluster I of Aphanizomenon flos-aquae selected from GenBank of the NCBI. The cyrA and cyrJ genes encoding for the cylindrospermopsin-biosynthesis were not detected in the present study. The sxtA gene was in detected both the two strains, whereas the sxtI gene which had been suggested as a suitable molecular marker to detect saxitoxin-producing cyanobacteria was not found both the strains. Thus, the two strains isolated from Nakdong River were identified as the same species of Aphanizomenon flos-aquae Ralfs ex Bornet et Flahault 1888, the two strains were confirmed as potential non-producing strains of the saxitoxin and cylindrospermopsin.

• Restorative Dentistry and Endodontics
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• v.32 no.2
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• pp.151-161
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• 2007

Dental caries is the most common disease in the oral cavity However, the mechanism and treatment of dental caries is not completely understood since many complex factors are involved. Especially the effect of pH on remineralization of early stage of dental caries is still controversial In this study, dental caries in dentin was induced by using lactic acidulated buffering solutions and the loss or inorganic substance was measured. Also decalcified specimens were remineralized by three groups of solution with different pH (group of pH 4.3, 5.0, and 5.5). Then, the amount and the area of inorganic substance precipitation was quantitatively analyzed with microradiograph. Also a qualitative comparison of the normal phase the demineralized phase, and the remineralized phase of hydroxyapatite crystal was made under SEM. The results were as follows, 1. In microradiograghic analysis, as the pH increased, the amount of remineralization in decalcified dentin tended to increase significantly As the pH decreaced, deeper decalcification, however, occurred along with remineralization. The group of pH 5.5 had a tendency to be remineralized without demineralization (p<0.05). 2. In SEM view, the remineralization in dentine caries occurred from the hydroxyapatite crystal surface surrounding the mesh of organic matrix, and eventually filled up the demineralized area. 3. 5 days after remineralization, hydroxyapatite crystal grew bigger with deposition of inorganic substance in pH 4.3 and 5.0 group, and the crystal in the remineralized area appeared to return to normal. After 10 days, the crystals in group of pH 4.3 and 5.0, which grew bigger after 5 days of remineralization, turned back to their normal size, but in group of pH 5.5, some crystals were found to double their size. In according to the results of this experiment, the decalcifying and remineralizing process of dentine is neither simple nor independent, but a dynamic process in which decalcification and remineralization occur simultaneously. The remineralization process occurred from the hydroxyapatite crystal surface.