• Title/Summary/Keyword: Modified materials

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Estimation of Oxygen Consumption Rate and Organic Carbon Oxidation Rate at the Sediment/Water Interface of Coastal Sediments in the South Sea of Korea using an Oxygen Microsensor (산소 미세전극을 이용한 남해연안 퇴적물/해수 계면에서 산소소모율 및 유기탄소 산화율 추정)

  • Lee, Jae-Seon;Kim, Kee-Hyun;Yu, Jun;Jung, Rae-Hong;Ko, Tae-Seung
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.8 no.4
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    • pp.392-400
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    • 2003
  • We used an oxygen microelectrode to measure the vertical profiles of oxygen concentration in sediments located near point sources of organic matter. The measurements were carried out between 13th and 17th May, 2003, in semi-closed bay and coastal sediments in the central part of the South Sea. The measured oxygen penetration depths were extremely shallow and ranged from 1.30 to 3.80 mm. This suggested that the oxidation and reduction reactions in the early diagenesis should be studied at the mm depth scale. In order to estimate the oxygen consumption rate, we applied the one-dimension diffusion-reaction model to vertical profiles of oxygen near the sediment/water interface. Oxygen consumption rates were estimated to be between 10.8 and 27.6 mmol O$_2$ m$\^$-2/ day$\^$-1/(average: 19.1 mmol O$_2$ m$\^$-2/ day$\^$-1/). These rates showed a positive correlation with the organic carbon of the sediments. The corresponding benthic organic carbon oxidation rates calculated using an modified Redfield ratio (170/110) at the sediment/water interface were in the range of 89.5-228.1 mg C m$\^$-2/ day$\^$-1/(average: 158.0 mg C m$\^$-2/ day$\^$-1/). We suggest that these results are maximum values at the presents situation in the bay because the sampling sites were located near point sources of organic materials. This study will need to be carried out at many coastal sites and throughout the seasons to allow an understanding of the mechanisms of eutrophication e.g. the spatial distribution of oxygen consumption within the oxic zone and hypoxic conditions in the coastal sea.

The effect of tumor necrosis factor (TNF)-α to induce matrix metalloproteinase (MMPs) from the human dental pulp, gingival, and periodontal ligament cells (사람의 치수, 치은, 치주인대 세포에 tumor necrosis factor (TNF)-α로 자극 시 matrix metalloproteinase (MMPs)의 분비에 관한 연구)

  • Rhim, Eun-Mi;Park, Sang-Hyuk;Kim, Duck-Su;Kim, Sun-Young;Choi, Kyoung-Kyu;Choi, Gi-Woon
    • Restorative Dentistry and Endodontics
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    • v.36 no.1
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    • pp.26-36
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    • 2011
  • Objectives: In the present study, three kinds of tissues cells (pulp, gingiva, and periodontal ligament) were investigated if those cells express MMP and TIMP when they were stimulated with neuropeptides (substance P, CGRP) or proinflammatory cytokine, TNF-$\alpha$. Materials and Methods: The cells cultured from human dental pulp (PF), gingiva (GF) and periodontal ligament were (PDLF) stimulated with Mock, SP, TNF-$\alpha$, and CGRP for 24 hrs and 48 hrs. for an RNase protection assay and Enzyme Linked Immunosorbent Assay. Cells (PF, GF and PDLF) seeded in 100 mm culture dish were stimulated with SP ($10^{-5}$, $10^{-8}\;M$) or only with medium (Mock stimulation) for 4hrs and for 24 hrs for RNase Protection Assay, and they were stimulated with CGRP ($10^{-5}\;M$) and TNF-$\alpha$(2 ng/mL) for 24 hrs and with various concentraion of TNF-$\alpha$(2, 10, and 100 ng/mL) for Rnase Protection Assay with a human MMP-1 probe set including MMP 1, 2, 8, 7, 8, 9, 12, and TIMP 2, 3. In addition, cells (PF, GF and PDLF) were stimulated with Mock and various concentraion of TNF-$\alpha$(2, 10, and 100 ng/mL) for 24 hrs and with TNF-$\alpha$(10 ng/mL) for 48 hrs, and the supernatents from the cells were collected for Enzyme Linked Immunosorbent Assay (ELISA) for MMP-1 and MMP-13. Results: The expression of MMPs in PF, GF, PDLF after stimulation with SP and CGRP were not changed compared with Mock stimulation for 4 hrs and 24 hrs. The expression of MMP-1, -12, -13 24 hrs after stimulation with TNF-$\alpha$ were upregulated, however the expression of TIMP-3 in PF, GF, PDLF after stimulation with TNF-$\alpha$ were downregulated. TNF-$\alpha$(2 ng/mL, 10 ng/mL, 100 ng/mL) increased MMP-1 and MMP-12 expression in PF dose dependently for 24 hrs. Conclusions: TNF-$\alpha$ in the area of inflammation may play an important role in regulating the remodeling of dentin, cementum, and alveolar bone.

Study on the Casting Technology and Restoration of "Sangpyong Tongbo" (상평통보 주조와 복원기술연구)

  • Yun, Yong-hyun;Cho, Nam-chul;Jeong, Yeong-sang;Lim, In-ho
    • Korean Journal of Heritage: History & Science
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    • v.47 no.4
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    • pp.224-243
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    • 2014
  • This study examined the materials and casting technology(cast, alloy, etc.) used in the manufacturing of bronze artifacts based on old literature such as Yongjae Chonghwa, Cheongong Geamul, and The Korea Review. In the casting experiment for restoration of Sangpyong Tongbo, a bronze and brass mother coin mold was made using the sand mold casting method described in The Korea Review. The cast was comprised of the original mold plate frame, wooden frame, and molding sand. Depending on the material of the outer frame, which contains the molding sand, the original mold plate frame can be either a wooden frame or steel frame. For the molding sand, light yellow-colored sand of the Jeonbuk Iri region was used. Next, the composition of the mother alloy used in the restoration of Sangpyong Tongbo was studied. In consideration of the evaporation of tin and lead during actual restoration, the composition of Cu 60%, Zn 30%, and Pb 10% for brass as stated in The Korea Review was modified to Cu 60%, Zn 35%, and Pb 15%. For bronze, based on the composition of Cu 80%, Sn 6%, and Pb 14% used for Haedong Tongbo, the composition was set as Cu 80%, Sn 11%, and Pb 19%. The mother coin mold was restored by first creating a wooden father coin, making a cast from the wooden frame and basic steel frame, alloying, casting, and making a mother coin. Component analysis was conducted on the mother alloy of the restored Sangpyong Tongbo, and its primary and secondary casts. The bronze mother alloy saw a 5% increase in copper and 4% reduction in lead. The brass parent alloy had a 5% increase in copper, but a 4% and 12% decrease in lead and tin respectively. Analysis of the primary and secondary mother coin molds using an energy dispersive spectrometer showed that the bronze mother coin mold had a reduced amount of lead, while the brass mother coin mold had less tin. This can be explained by the evaporation of lead and tin in the melting of the primary mother coin mold. In addition, the ${\alpha}$-phase and lead particles were found in the mother alloy of bronze and brass, as well as the microstructure of the primary and secondary coin molds. Impurities such as Al and Si were observed only in the brass mother coin mold.

A Study of the Construction and Change of Chugyeongwon in Donggweol (동궐(東闕) 추경원(秋景苑)의 조영과 변천에 관한 고찰)

  • Oh, Jun-young
    • Korean Journal of Heritage: History & Science
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    • v.52 no.1
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    • pp.44-63
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    • 2019
  • This study empirically investigated the construction and aspects of change in Chugyeongwon, which is located in Donggweol (東闕). In detail, this study investigated the location of the construction and range of Chugyeongwon, the background and intention of the construction, and the affiliated system and aspects of spatial changes of it. The research results can be summarized as follows: First, Chugyeongwon has been assumed to be the space near Haminjeong (涵仁亭) or between Simindang (時敏堂) and Jinsudang (進修堂) in Changgyeonggung Palace. However, according to related historical materials, it is said that Chugyeongwon was located west of Dochongbu (都摠府) in Hyeopsangmun (協祥門) and near Sungmundang (崇文堂). Through Donggweoldohyeong (東闕圖形), evidence of the construction of Chugyeongwon can be found, which verifies such claims. According to The Plan of Changgyeonggung Palace (昌慶宮配置圖), in the form of modern measured drawing, Chugyeongwon today is the green space created in the south of Munjeongjeon (文政殿) and Sungmundang in Changgyeonggung Palace. Second, According to Donggweoldo (東闕圖), Chugyeongwon was a green space where trees grew on the ground within the walls. No artificial facilities were constructed inside. In addition, Chugyeongwon was located at a site with an altitude higher than the surroundings. Especially, the composition forms and location characteristics of Chugyeongwon are similar to those of the Palace Outer Garden located in Hanyang. Thus, based on this evidence about the form and other aspects of the operation of the Palace Outer Garden, it can be inferred that Chugyeongwon was constructed for the preservation and cultivation of the geographical features inside Donggweol. Third, in the late Joseon period, Chugyeongwon was assigned to Changdeokgung Palace or Changgyeonggung Palace in the same manner as was Donggung (東宮). Thus, it is very likely that Chugyeongwon served as a garden for the Royal Family in the Donggung area. The west boundary of Chugyeongwon, which originally consisted of walls and a side gate, was changed into the form in which the walls and colonnades were combined. Chugyeongwon has been modified due to various acts of development since the Japanese colonial era, and in the end, it has disappeared so that no trace can be found.

Report on the improvement of the in vitro and specimen reception environment system (핵의학과 검체 접수 환경시스템의 개선사례 보고)

  • Kim, Jung In;Kang, Mi Ji;Kim, Na Kyung;Park, Ji Sol;Kwon, Won Hyun;Lee, Kyung Jae
    • The Korean Journal of Nuclear Medicine Technology
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    • v.25 no.2
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    • pp.29-34
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    • 2021
  • Purpose Sample reception environment system in nuclear medicine has not changed much compared to 20 years ago. When preparing sample for in vitro test, there was no significant change because the test was carried out by generating an own specimen from the parent specimen. In this study, We would like to introduce a method that automatically removes the sample cap using the automated decapper equipment and enables automatic reception at the same time. In addition, including a provisional reception system. Materials and Methods In 2019, it was intended to get a device that automatically removes the cap of a patient's blood sample. This equipment is the same as the equipment used in the Department of Laboratory Medicine (Vacuette Ⓡ Unicap Belt Decapper, Greiner bio-one, Austria). However, the purchase was delayed due to differences in tube size, budget, and space. In January 2020, we borrowed domestic automatic decapper equipment and modified it to suit our laboratory environment. After 9 months, we were able to introduce a system that automatically removes the lid of a patient's blood sample and at the same time automatically accepts the test. And, through the provisional reception system, it was possible to know the arrival of the specimen in a short time. Results With the use of an automatic decapper device, the sample cap was automatically removed, and the reception proceeded at the same time. So, it was very efficient at work because it shortened the sample preparation time by about 20 minutes. In addition, it was possible to prevent the examiner's musculoskeletal disorders caused by repeated wrist use. After using the provisional reception system, patients were able to be discharged quickly, and the number of phone calls to confirm the arrival of samples was reduced. Conclusion Most hospitals have about four employees in the nuclear medicine in vitro laboratory. It is effective to use automatic decapper equipment and a provisional reception system for organizations that perform work with the minimum number of personnel.

A Study on the Establishment of Preservation Area for the Preservation of Historical and Cultural Space in the Ancient Village - Focused on the Hongcun, China - (고촌락 역사문화공간 보존을 위한 보호구역 설정 방안 연구 - 중국 굉촌을 중심으로 -)

  • Shin, Hyun-Sil;Dai, Gai-Rong
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.40 no.1
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    • pp.65-73
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    • 2022
  • This paper analyzed the characteristics of ancient villages in Hongcun and the method of resetting the preservation area for the preservation of the changed historical and cultural space in Hongcun through the process of change. To this end, the current status of preservation areas and utilization areas in the village was identified through ancient documents, old paintings, policy materials, and interviews related to the village, and through this, the problem of resetting the preservation area was examined. As a result, the following conclusions were drawn. First, Hongcun is a village built under the influence of Confucianism, Buddhism, and Taoism, and the spatial organization was created according to the hierarchy of Confucianism. As a result, it was possible to inherit and preserve the heritage of ancestors even though the central government did not preserve it. Second, the concept of preservation in a limited sense has been applied as Hongcun has been recognized as a cultural heritage that has been passed down since ancient times, but the Great Leap Forward and the Cultural Revolution brought about changes in the village space. Since then, ancient buildings, water systems, and forests have been preserved through regulations on new construction and expansion of a building with the Hongchon preservation plan, but the development within the preservation area is underway due to changes in the lives of original inhabitants, which were followed by continued development pressure and reform and opening. Third, the original inhabitant of ancient villages had a high perception of the value of the heritage, but they demanded the preparation of measures to improve living conditions and create profits, and the active use of villages for this. Fourth, the forest consisting of old trees is being restored, but the gardens in the old house are showing a phenomenon that the garden space is reduced or transformed for use. The bridges and parking lots were newly built in the southern area, which was extended from the western area, the original entrance to the ancient village, resulting in changes in the existing entrance. This was found to be the primary cause of the spatial change of the ancient village, as the road system was modified to make it convenient for tourists to enter and exit. Fifth, the existing preservation area should be reset and preserved by resetting the preservation route centered on Wolso(half Moon Pool), while the surrounding area should be set as a direct and indirect experience space, and according to the hierarchy of each space, the utilization should proceed while the preservation is carried out by crossing the preservation and the utilization.

Reliability and validity of Korean version of the OHIP for edentulous subjects: A pilot study (무치악 환자들을 위한 한국어 버전의 구강건강영향지수 신뢰도와 타당성 평가를 위한 모의연구)

  • Shin, Jae Seob;Bae, So Young;Park, Jin Hong;Shim, Ji Suk;Lee, Jeong Yol
    • The Journal of Korean Academy of Prosthodontics
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    • v.59 no.3
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    • pp.305-313
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    • 2021
  • Purpose. The purpose of this pilot study is to evaluate the reliability and validity of the Korean version of the oral health impact profile (OHIP-EDENT K) for edentulous patients. Materials and methods. The study was conducted on 12 patients who fabricated overdenture in the Department of Prosthodontics, Korea University, Guro Hospital. All subjects completed the Korean version of Oral Health Impact Profile (OHIP K) questionnaire. Shorten version of the OHIP called OHIP-14 K and OHIP-EDENT K were derived from the datasets. Cronbach's alpha was used to measure internal consistency of the summary scores for OHIP-EDENT K. The Spearman's correlation coefficient between the summary scores for OHIP-EDENT K and OHIP K was calculated to evaluate concurrent validity. Results. The reliability of the summary scores for OHIP-EDENT K was acceptable (α=.736). The Spearman's correlation coefficient of the summary scores for OHIP-EDENT K and OHIP K was 0.966, which was statistically significant (P<.001). OHIP-EDENT K exhibited less susceptibility to floor effects than OHIP-14 K and appeared to measure change as effectively as OHIP K. In order to prove the reliability, responsiveness and validity of OHIP-EDENT K, further studies with more samples are needed. Conclusion. The OHIP-EDENT K, a questionnaire on oral health-related QOL comprising 19 items, has measurement properties comparable with the full 49-item version. This modified shortened version can be an alternative questionnaire to full version of OHIP K and OHIP-14 K in edentulous patients.

The Trend of Cigarette Design and Tobacco Flavor System Development

  • Wu, Jimmy Z.
    • Journal of the Korean Society of Tobacco Science
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    • v.24 no.1
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    • pp.67-73
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    • 2002
  • In light of addressing consumer health concern, coping with anti-tobacco movement, and promoting new product, tobacco industry is actively pursuing to make a new generation of cigarettes with low tar and nicotine deliveries, and less harmful substances. Low tar and low nicotine cigarettes increases their market shares dramatically world wide, especially in KT&G, multinational tobacco companies, EU countries, even in China regulated by CNTC to set up yearly target to lower tar and nicotine deliveries. On the other hand, to design a new cigarette with reduced harmful substances begins to gain speed. The "modified Hoffmann list" publishes thirty plus substances in tobacco leaf and main smoke stream, which is the prime suspect causing health problems. Various ways and means are developed to reduce such components including new tobacco breeds, new curing method, tobacco leaf treatment before processing, selected filtration system, innovated casing system to reduce free radicals, as well as some non conventional cigarette products. In TSRC held this year, the main topic is related to reduce tobacco specific nitrosamines in tobacco leaf. The new generation of cigarette is in the horizon. It still needs a lot help to produce commercial products with satisfied taste and aroma characters. The flavor industry is not regulated by many governments demanding which ingredients might or might not be for tobacco use. However, most of the cigarette companies self impose a list of ingredients to guide flavor suppliers to design flavors. Unfortunately, the number of ingredients in those lists is getting shorter every year. It is understandable that the health is not the only reason. Some cigarette companies are playing safe to protect the company from potential lawsuit, while others are just copying from their competitors. Moreover, it is obvious that it needs more assistance from casings and flavors to design new generation of cigarettes with missing certain flavor components in tobacco leaf and main smoke stream. These flavor components are either non-existed or at lower level at new form of cured tobacco leaf or filtered in the main smoke stream along with reduced harmful substances. The use of carbon filters and other selected filtration system poses another tough task for flavor system design. Specific flavor components are missing from the smoke analysis data, which brings a notion of "carbon taste" and "dryness" of mouth feel. It is ever more demanded by cigarette industry to flavor suppliers to produce flavors as body enhancer, tobacco notes, salivating agents, harshness reducer, and various of aromatic notes provided they are safe to use. Another trend is that water based flavor or flavor with reduced ethanol as solvent is gaining popularity. It is preferred by some cigarette companies that the flavor is compounded with all natural ingredients or all ingredients should he GMO free. The new generation of cigarettes demands many ways of new thinking process. It is also vital for tobacco industry. It reflects the real needs for the consumers that the cigarette product should be safe to use as well as bearing the taste and aroma characters smokers always enjoyed. An effective tobacco flavor system is definitely a part of the equation. The global trend of tobacco industry is like trends of any other industries lead by consumer needs, benefited with new technology availability, affected by the global economy, and subjected for various rules and regulations. Anti-tobacco organizations and media exceptionally scrutinize cigarette, as a legal commercial product. Cigarette is probably the most studied commercial product for its composition, structure, deliveries, effects, as well as its new developmental trend. Therefore, any new trend of cigarette development would be within these boundaries. This paper is trying to point out what it would be like for tobacco industry in the next few yews and what concerns the tobacco industry. It focuses mostly on the efforts to produce safer cigarettes. It is such a vital task for the tobacco industry and its affiliate industries such as cigarette papers, filters, flavors, and other materials. The facts and knowledge presented in this paper might be well known for the public. Some of the comments and predictions are very much personal opinion for a further discussion.

A Study on Problems and Improvement of Home-help Services of Long-term Care Insurance (노인장기요양보험 재가서비스의 문제점과 개선방안)

  • Lee, Jun Woo;Jin, Hee
    • 한국노년학
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    • v.29 no.1
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    • pp.149-175
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    • 2009
  • The purpose of this research is to analyze the overall problems at the moment of October 2008, and then to find the improvements of home-help services of the Long-Term Care Insurance(LTCI), which has been revealed many problems since it was released in July 2008. The research uses the literature survey which analyzes 2nd-hand materials studied by other people already, and survey research was executed from active social workers in the area of LTCI. Based on the policy analysis framework of Gilbert and Specht, all the data are analyzed in the scopes of client·benefit(service)·finance·transferring system. This research has found the problems in each scope of home-help services of the LTCI. Firstly, the client system has some problems in mismatching between registered and service clients, estimating client number, and judging service levels. Secondly, the service system reveals deficiency in professionality of social workers, service quality lowering by loose qualification criteria on workers, non-reasonable limitation of service time available, and the same fare system applied to visiting-help service in spite of different levels. Thirdly, in financing system, clients need to pay additional money to get extra services such as meal, hair cutting, bathing etc., due to government financial support stopped, some organizations have to reduce services and replace full-time workers to part-time ones, which makes the service quality worse. Lastly, in the transferring system, the management system for service quality is not well prepared. There are too much competion because of allowing too many home-help service organizations and care worker academies. The suggestions that this research has found to improve the policy are as follows. ① It is desirable to make the registered clients the service ones as many as possible in the long term perspective. ② The LTCI organization requires more workers and higher professionality. ③ Many elderly people who are not eligible now require connection system to be more served. ④ Management system and service manual for care worker are to be developed. ⑤ Laws related to the service contents and process should be modified, the proportion of client charge needs to adjust. ⑥ Home-help service organization licensed by the LTCI needs to be financially supported publicly. ⑦ Monitoring system to home-help service organization needs to be strengthened. ⑧ Evaluation tools to home-help service organization and workers is required. ⑨ Specification to open the home-help service organization needs to be more strict.

Single Center Experience of the Balloon-Stent Technique for the Treatment of Unruptured Distal Internal Carotid Artery Aneurysms: Sharing a Simple and Reliable Tip to Use Scepter-Atlas Combination (원위내경동맥에 위치한 비파열성 동맥류의 치료에 있어 풍선-스텐트 테크닉에 대한 단일기관의 경험: Scepter-Atlas 조합을 사용하기 위한 간단하지만 확실한 방법)

  • Yu-jung Park;Jieun Roh;Seung Kug Baik;Jeong A Yeom;Chul-Hoo Kang;Hee Seok Jeong;Sang Won Lee
    • Journal of the Korean Society of Radiology
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    • v.82 no.5
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    • pp.1258-1273
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    • 2021
  • Purpose The balloon-stent technique (BST) has certain strengths as an assisted technique for the treatment of complex aneurysms. After Atlas release, the BST can be executed without an exchange maneuver of the balloon to the stent-delivery catheter. The purpose of this article is to share our experience with the BST using the Scepter-Atlas combination. Materials and Methods Device inspection led us to a simple method to avoid failure in loading Atlas to the Scepter. From March 2018 to December 2019, 57 unruptured distal internal carotid artery (dICA) aneurysms were treated with coil embolization; among which, 25 aneurysms in 23 patients were treated with BST. Clinical and angiographic data were retrospectively collected and reviewed. Results The technical success rate of the Scepter-Atlas combination increased from 50% to 100% after careful inspection. BST angiographic results were comparable to the stent-assisted coil (SAC) group treated during the immediately post-embolization same period (modified Raymond-Roy classification [MRRC] 1 & 2 84% in BST, 96.3% in SAC) and during short-term follow-up (MRRC 1 & 2 95.8% in BST, 88.4% in SAC). A small number of patients showed periprocedural complications, but none had clinical consequences. Conclusion BST using the Scepter-Atlas combination can provide an effective and safe method for the treatment of dICA aneurysms. Scepters can be used as delivery catheters for Atlas.