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Clinical Efficacy of Bunny Multifocal Intraocular Lens after Cataract Surgery (버니 다초점인공수정체의 임상적 효용성)

  • Cho, Myung Ho;Park, Jae Yeong;Park, Byung Gun;Lee, Jong Soo
    • Journal of The Korean Ophthalmological Society
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    • v.59 no.12
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    • pp.1129-1136
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    • 2018
  • Purpose: To compare the postoperative clinical outcomes after cataract surgery and implantation using the BunnyLens $MF^{(R)}$ and $ReSTOR^{(R)}$ multifocal intraocular lenses. Methods: Sixty-five eyes implanted with multifocal intraocular lenses were divided into two groups involving either $ReSTOR^{(R)}$ (39 eyes) or BunnyLens $MF^{(R)}$ (26 eyes) lenses. In these two groups, the distant and near visual acuity, astigmatism, spherical equivalent, and contrast sensitivity test were examined at preoperative and postoperative 1 week, 8 weeks, and 24 weeks. We compared the clinical efficacy between the two groups before and after cataract surgery using statistical analysis. Results: The mean value of distant and near visual acuity, and spherical equivalent of both groups after intraocular lens implantation were significantly improved, compared with the preoperative values (p < 0.05), while there was no significant differences between the two groups (p > 0.05). The means of postoperative distant and near visual acuity, astigmatism, and contrast sensitivity test were not significantly different between $ReSTOR^{(R)}$ and BunnyLens $MF^{(R)}$ lenses (p > 0.05). The mean numeric error of spherical equivalent at the final postoperative 24 weeks was $-0.17{\pm}0.50$ diopters (D) for the $ReSTOR^{(R)}$ lenses and $-0.34{\pm}0.52D$ for the BunnyLens $MF^{(R)}$ lenses (p > 0.05). Conclusions: BunnyLens $MF^{(R)}$ and $ReSTOR^{(R)}$ lenses showed no significant difference in clinical efficacy, including distance and near vision, spherical equivalent error, and contrast sensitivity test after cataract surgery. However, it should be noted that BunnyLens $MF^{(R)}$ lenses had a tendency toward myopic shift compared with $ReSTOR^{(R)}$ lenses.

Validation of Satellite Scatterometer Sea-Surface Wind Vectors (MetOp-A/B ASCAT) in the Korean Coastal Region (한반도 연안해역에서 인공위성 산란계(MetOp-A/B ASCAT) 해상풍 검증)

  • Kwak, Byeong-Dae;Park, Kyung-Ae;Woo, Hye-Jin;Kim, Hee-Young;Hong, Sung-Eun;Sohn, Eun-Ha
    • Journal of the Korean earth science society
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    • v.42 no.5
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    • pp.536-555
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    • 2021
  • Sea-surface wind is an important variable in ocean-atmosphere interactions, leading to the changes in ocean surface currents and circulation, mixed layers, and heat flux. With the development of satellite technology, sea-surface winds data retrieved from scatterometer observation data have been used for various purposes. In a complex marine environment such as the Korean Peninsula coast, scatterometer-observed sea-surface wind is an important factor for analyzing ocean and atmospheric phenomena. Therefore, the validation results of wind accuracy can be used for diverse applications. In this study, the sea-surface winds derived from ASCAT (Advanced SCATterometer) mounted on MetOp-A/B (METeorological Operational Satellite-A/B) were validated compared to in-situ wind measurements at 16 marine buoy stations around the Korean Peninsula from January to December 2020. The buoy winds measured at a height of 4-5 m from the sea surface were converted to 10-m neutral winds using the LKB (Liu-Katsaros-Businger) model. The matchup procedure produced 5,544 and 10,051 collocation points for MetOp-A and MetOp-B, respectively. The root mean square errors (RMSE) were 1.36 and 1.28 m s-1, and bias errors amounted to 0.44 and 0.65 m s-1 for MetOp-A and MetOp-B, respectively. The wind directions of both scatterometers exhibited negative biases of -8.03° and -6.97° and RMSE values of 32.46° and 36.06° for MetOp-A and MetOp-B, respectively. These errors were likely associated with the stratification and dynamics of the marine-atmospheric boundary layer. In the seas around the Korean Peninsula, the sea-surface winds of the ASCAT tended to be more overestimated than the in-situ wind speeds, particularly at weak wind speeds. In addition, the closer the distance from the coast, the more the amplification of error. The present results could contribute to the development of a prediction model as improved input data and the understanding of air-sea interaction and impact of typhoons in the coastal regions around the Korean Peninsula.

Evaluation of beam delivery accuracy for Small sized lung SBRT in low density lung tissue (Small sized lung SBRT 치료시 폐 실질 조직에서의 계획선량 전달 정확성 평가)

  • Oh, Hye Gyung;Son, Sang Jun;Park, Jang Pil;Lee, Je Hee
    • The Journal of Korean Society for Radiation Therapy
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    • v.31 no.1
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    • pp.7-15
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    • 2019
  • Purpose: The purpose of this study is to evaluate beam delivery accuracy for small sized lung SBRT through experiment. In order to assess the accuracy, Eclipse TPS(Treatment planning system) equipped Acuros XB and radiochromic film were used for the dose distribution. Comparing calculated and measured dose distribution, evaluated the margin for PTV(Planning target volume) in lung tissue. Materials and Methods : Acquiring CT images for Rando phantom, planned virtual target volume by size(diameter 2, 3, 4, 5 cm) in right lung. All plans were normalized to the target Volume=prescribed 95 % with 6MV FFF VMAT 2 Arc. To compare with calculated and measured dose distribution, film was inserted in rando phantom and irradiated in axial direction. The indexes of evaluation are percentage difference(%Diff) for absolute dose, RMSE(Root-mean-square-error) value for relative dose, coverage ratio and average dose in PTV. Results: The maximum difference at center point was -4.65 % in diameter 2 cm size. And the RMSE value between the calculated and measured off-axis dose distribution indicated that the measured dose distribution in diameter 2 cm was different from calculated and inaccurate compare to diameter 5 cm. In addition, Distance prescribed 95 % dose($D_{95}$) in diameter 2 cm was not covered in PTV and average dose value was lowest in all sizes. Conclusion: This study demonstrated that small sized PTV was not enough covered with prescribed dose in low density lung tissue. All indexes of experimental results in diameter 2 cm were much different from other sizes. It is showed that minimized PTV is not accurate and affects the results of radiation therapy. It is considered that extended margin at small PTV in low density lung tissue for enhancing target center dose is necessary and don't need to constraint Maximum dose in optimization.

Geographical Variation of the Oriental Fruit Fly, Bactrocera dorsalis, Occurring in Taiwan (오리엔탈과실파리 유전변이 - 대만 지역 집단변이)

  • Kim, Yonggyun;Kim, Hyoil;Mollah, Md. Mahi Imam;Al Baki, Md. Abdullah
    • Korean journal of applied entomology
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    • v.58 no.2
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    • pp.133-142
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    • 2019
  • This study analyzed genetic variation of the Oriental fruit fly (OFF), Bactrocera dorsalis, which is designated to be a quarantine insect pest in Korea. OFF samples endemic to Taiwan were collected at three different locations (Taipei, Taichung, and Kaohsiung) for three days from July 30 to August 1 in 2018 and assessed in their age and mitochondrial DNA sequence variations. In these places, 1,085 OFF males were collected using methyl eugenol lure while 30 males of Zeugodacus cucurbitae and one male of Bactrocera tau were collected using Cuelure. A protein diet lure attracted 6 flies including one OFF and 5 flies of Z. cucurbitae. Male heads of OFF contained pterin, which increased in contents with age from 32 to $59{\mu}g/head$. There was a local variation in pterin amounts in OFF heads, in which Kaohsiung population had lower amounts of pterin than Taipei and Taichung populations. Genetic distance among these three populations were measured by random amplified polymorphic DNA and showed that Taipei population was separated from Taichung/Kaohsiung cluster. Genetic variation was also analyzed in sequence variations in cytochrome oxidase I (CO-I) and NADH dehydrogenase I (ND-I). There was 7.8% variation in CO-I sequence (360 residues) and 6.6% variation in ND-I sequence (213 residues). These polymorphic sites are proposed to be used to develop SNP (single nucleotide polymorphism) markers characteristic to Taiwan OFF populations.

Formative Characteristics of Water Space and Scenic Spot of Baegun-dong Wonlim in Gangjin Aaun Village (강진 안운마을 백운동원림의 승경과 수공간의 조영 특성)

  • Park, Yool-Jin;Kim, Hong-Gyun;Rho, Jae-Hyun;Kim, Hwa-Ok;Goh, Yea-Bin
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.29 no.2
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    • pp.99-107
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    • 2011
  • This study is aiming to acquire data for enhancing genuineness of restoration through reviewing external and internal scenery of Baegun-dong Wonlim such as Baegun-dong 8 Objects of Scenery(pines, bamboos, chrysanthemum, orchid, maehwa blossom, magnolia, fiddle and crane) and 12 Scenic Spots and reviewing internal and external scenery of Baegun-dong Wonlim such as views and scenery for plantation. For Baegun-dong 8 Young which sang songs about scenic spots of Baegun-dong Wonlim it seemed that its head words were formed through borrowing rhyming words from caption of Baegun-dong Yuseogi(白雲洞幽棲記). Accordingly it seemed these scenery secured its status of Wonlim from the beginning. Particularly the words of fiddle and crane in 琴棋書畵(Geumgisuhha) implied that playing Komungo and brushwriting were firmly rooted as romantic pursuits of classical scholars of that time. In consideration of distance upto Okpanbong which is one of 12 scenic spots of Baegun-dong radius of outer circumference is estimated to be around 1.6km. From Okgpanbong, the epicenter, Sandagyeong, Baegokmae, Hongokpok and Pungdan etc. correspond to transitional space. And inner scenery was formed with hub of thatched cottages and bowers surrounded with chrysanthemums, poenies, rhododendron, Phyllostachys bambusoides, pines and upper and lower water paths. Thus it seemed there was scenic structure of centrifugal nature as well as of multiplicity. Forms of majority of water paths with residual structure found in the country have streamlined forms on the other hand Baegun-dong water paths have straight line which almost dominate inner gardens in terms of scale and forms thus revealing its extraordinary idea and design. In order to promote genuine restoration of Baegun-dong Wonlim it will be necessary to have consideration from standpoint of managing perspective to assure presentation of gradual scenery with elements of scenic objects for outer view among 12 Scenic Spots.

Phylogeographic and population genetic study of a Korean endemic freshwater fish species, Zacco koreanus (한국 고유 담수어종 참갈겨니(Zacco koreanus) 개체군의 계통지리학 및 집단유전학 연구)

  • Kim, Yu Rim;Jang, Ji Eun;Choi, Hee-kyu;Lee, Hyuk Je
    • Korean Journal of Environmental Biology
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    • v.38 no.4
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    • pp.650-657
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    • 2020
  • We conducted a phylogeographic analysis of Korean endemic Zacco koreanus populations inhabiting the East-flowing river (Gangneung Yeongokcheon; GY, Yangyang Namdaecheon; YN), the Han River (Seomgang; SG, Soksacheon; SS), and the Nakdong River(Gilancheon; GA) using the mitochondrial DNA cytochrome oxidase I (COI) gene (619 bp). Population genetic analysis was further performed to assess the population connectivity for the GY river where there is a large number of human-made artificial weirs with several fishways. The phylogeographic analysis revealed that while the populations of the East-flowing river and those of the Han River formed a monophyletic lineage, the Nakdong River individuals represented a distinct lineage with 3.7-4.2% (mean=4.0%) genetic distance from the other lineages. The population genetic analysis of the GY showed that a mid-stream population harbored relatively higher mitochondrial diversity relative to up- and down-stream populations, and there was no genetic differentiation between these three populations. The latter findings might suggest high genetic connectivity between the populations via genetic flow along the fishways. However, an analysis using faster-evolving genetic markers, such as microsatellites, is needed to confirm the findings of high population connectivity. Our study suggests the possibility of the presence of cryptic species in Z. koreanus in the Nakdong River basin. However, further study with more individual samples as well as additional markers or even more advanced genomic tools is required to test our hypothesis. Ecological or phenotypic analyses should be conducted to test whether the observed Nakdong River lineage represents a different or cryptic species, or simply hidden, but excessive, intraspecific diversity.

Interviews on Learner's Interest in Learning of Lifelong Education Center in University (대학 평생교육원 학습자의 학습흥미유발에 대한 인터뷰)

  • Kim, Young-Woo
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.2
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    • pp.145-154
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    • 2019
  • The purpose of this study is to investigate the performance, learning motivation and satisfaction of the students who take the university 's Lifelong Education Program. The research method was interviewed. The results are as follows. In terms of operations; First, the awareness of the kindness of employees of the college lifelong education institute needs to be strengthened at the beginning of the school year. Second, in the operation of the College Lifelong Education Center, the support such as the parking fee should be extended to the students. Third, lifelong education facilities should be supplemented. In terms of participation motivation; First, it can be seen that there are the most learners who want to do complementary learning. Most of them are people who look back on their lives and prepare for their future directions. Second, as the life span of human beings became longer, the economic preparation for life became necessary. Thus, all learning tends to be perceived as a preparation for economic income. Third, most people who participate in lifelong education are very interested in health. Therefore, it is necessary to increase the motivation for participation by expanding health related programs. In terms of satisfaction; First, it depends on the purpose of the individual. Satisfaction was high for those who aimed at hobbies and relationships, and satisfaction for those who aimed for economic activities was low. Second, it is also necessary to consider the instructor 's instructional process. In other words, lifelong learners tend to be adults, so little complaints are not revealed. Therefore, I would like to ask the lecturers to advance the education for the class. The implications for the improvement direction of the lifelong education center are as follows; First, we need to drastically reduce the number of programs overlapping with other universities and conduct research to develop new programs. In order to do this, it is necessary to continuously carry out a survey of demanders' needs. Second, it is necessary to find the appropriate place for program operation considering the movement distance of learners. It should be avoided that the program should be operated with the existing university facilities. Third, universities' lifelong education should go to education that includes college students.

Effects of drumming exercise on the autonomic nervous system in overweight women (드러밍 운동이 과체중 여성의 자율신경계에 미치는 영향)

  • Jeong In Kwon;Jae Hoon Lee;Joon Yong Cho;Yoo Sung Oh
    • Journal of the Korean Applied Science and Technology
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    • v.41 no.2
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    • pp.219-232
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    • 2024
  • The aim of this study was to explore the impact of body mass index (BMI) and drumming exercise on autonomic nervous system function in adult women. Ten adult women (aged 30-50) were divided into two groups based on their BMI: a normal BMI group (Low BMI, LBMI < 23 kg/m2) and an overweight BMI group (High BMI, HBMI > 23 kg/m2). Both groups participated in a drumming exercise program, consisting of 50-minute sessions, three times a week, for a duration of 8 weeks. Body composition and heart rate variability were assessed before and after the 8-week exercise period. Heart rate variability was evaluated using linear analysis in the time domain and frequency domain. Additionally, non-linear analysis was conducted using a Poincaré plot. The autonomic nervous system index was determined by measuring parasympathetic nervous system index and sympathetic nervous system index. Following the 8-week intervention, the HBMI group exhibited a significant decrease in weight (p=0.034), BMI (p=0.044), body fat mass (p=0.032), and waist circumference (p=0.013) compared to the LBMI group. Furthermore, the HBMI group demonstrated significant increases in RMSSD (p=0.018) and TP (p=0.033) in linear analysis, as well as SD1 (p=0.018) in non-linear analysis and PNS Index (p=0.040) compared to the LBMI group. RMSSD, SD1, and PNS Index serve as indicators of parasympathetic nervous system activity in linear and non-linear analyses, respectively. These findings indicate that drumming exercise significantly enhances autonomic nervous system function in overweight women.

Efficacy and Accuracy of Patient Specific Customize Bolus Using a 3-Dimensional Printer for Electron Beam Therapy (전자선 빔 치료 시 삼차원프린터를 이용하여 제작한 환자맞춤형 볼루스의 유용성 및 선량 정확도 평가)

  • Choi, Woo Keun;Chun, Jun Chul;Ju, Sang Gyu;Min, Byung Jun;Park, Su Yeon;Nam, Hee Rim;Hong, Chae-Seon;Kim, MinKyu;Koo, Bum Yong;Lim, Do Hoon
    • Progress in Medical Physics
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    • v.27 no.2
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    • pp.64-71
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    • 2016
  • We develop a manufacture procedure for the production of a patient specific customized bolus (PSCB) using a 3D printer (3DP). The dosimetric accuracy of the 3D-PSCB is evaluated for electron beam therapy. In order to cover the required planning target volume (PTV), we select the proper electron beam energy and the field size through initial dose calculation using a treatment planning system. The PSCB is delineated based on the initial dose distribution. The dose calculation is repeated after applying the PSCB. We iteratively fine-tune the PSCB shape until the plan quality is sufficient to meet the required clinical criteria. Then the contour data of the PSCB is transferred to an in-house conversion software through the DICOMRT protocol. This contour data is converted into the 3DP data format, STereoLithography data format and then printed using a 3DP. Two virtual patients, having concave and convex shapes, were generated with a virtual PTV and an organ at risk (OAR). Then, two corresponding electron treatment plans with and without a PSCB were generated to evaluate the dosimetric effect of the PSCB. The dosimetric characteristics and dose volume histograms for the PTV and OAR are compared in both plans. Film dosimetry is performed to verify the dosimetric accuracy of the 3D-PSCB. The calculated planar dose distribution is compared to that measured using film dosimetry taken from the beam central axis. We compare the percent depth dose curve and gamma analysis (the dose difference is 3%, and the distance to agreement is 3 mm) results. No significant difference in the PTV dose is observed in the plan with the PSCB compared to that without the PSCB. The maximum, minimum, and mean doses of the OAR in the plan with the PSCB were significantly reduced by 9.7%, 36.6%, and 28.3%, respectively, compared to those in the plan without the PSCB. By applying the PSCB, the OAR volumes receiving 90% and 80% of the prescribed dose were reduced from $14.40cm^3$ to $0.1cm^3$ and from $42.6cm^3$ to $3.7cm^3$, respectively, in comparison to that without using the PSCB. The gamma pass rates of the concave and convex plans were 95% and 98%, respectively. A new procedure of the fabrication of a PSCB is developed using a 3DP. We confirm the usefulness and dosimetric accuracy of the 3D-PSCB for the clinical use. Thus, rapidly advancing 3DP technology is able to ease and expand clinical implementation of the PSCB.

A Consideration of Apron's Shielding in Nuclear Medicine Working Environment (PET검사 작업환경에 있어서 APRON의 방어에 대한 고찰)

  • Lee, Seong-wook;Kim, Seung-hyun;Ji, Bong-geun;Lee, Dong-wook;Kim, Jeong-soo;Kim, Gyeong-mok;Jang, Young-do;Bang, Chan-seok;Baek, Jong-hoon;Lee, In-soo
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.1
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    • pp.110-114
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    • 2014
  • Purpose: The advancement in PET/CT test devices has decreased the test time and popularized the test, and PET/CT tests have continuously increased. However, this increases the exposure dose of radiation workers, too. This study aims to measure the radiation shielding rate of $^{18}F-FDG$ with a strong energy and the shielding effect when worker wore an apron during the PET/CT test. Also, this study compared the shielding rate with $^{99m}TC$ to minimize the exposure dose of radiation workers. Materials and Methods: This study targeted 10 patients who visited in this hospital for the PET/CT test for 8 days from May 2nd to 10th 2013, and the $^{18}F-FDG$ distribution room, patient relaxing room (stand by room after $^{18}F-FDG$ injection) and PET/CT test room were chosen as measuring spots. Then, the changes in the dose rate were measured before and after the application of the APRON. For an accurate measurement, the distance from patients or sources was fixed at 1M. Also, the same method applied to $^{99m}TC's$ Source in order to compare the reduction in the dose by the Apron. Results: 1) When there was only L-block in the $^{18}F-FDG$ distribution room, the average dose rate was $0.32{\mu}Sv$, and in the case of L-blockK+ apron, it was $0.23{\mu}Sv$. The differences in the dose and dose rate between the two cases were respectively, $0.09{\mu}Sv$ and 26%. 2) When there was no apron in the relaxing room, the average dose rate was $33.1{\mu}Sv$, and when there was an apron, it was $22.3{\mu}Sv$. The differences in the dose and dose rate between them were respectively, $10.8{\mu}Sv$ and 33%. 3) When there was no APRON in the PET/CT room, the average dose rate was $6.9{\mu}Sv$, and there was an APRON, it was $5.5{\mu}Sv$. The differences in the dose and dose rate between them were respectively, $1.4{\mu}Sv$ and 25%. 4) When there was no apron, the average dose rate of $^{99m}TC$ was $23.7{\mu}Sv$, and when there was an apron, it was $5.5{\mu}Sv$. The differences in the dose and dose rate between them were respectively, $18.2{\mu}Sv$ and 77%. Conclusion: According to the result of the experiment, $^{99m}TC$ injected into patients showed an average shielding rate of 77%, and $^{18F}FDG$ showed a relatively low shielding rate of 27%. When comparing the sources only, $^{18F}FDG$ showed a shielding rate of 17%, and $^{99m}TC$'s was 77%. Though it had a lower shielding effect than $^{99m}TC$, $^{18}F-FDG$ also had a shielding effect on the apron. Therefore, it is considered that wearing an apron appropriate for high energy like $^{18}F-FDG$ would minimize the exposure dose of radiation workers.

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