• Title/Summary/Keyword: 구조적안전

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Preservation of Subvalvular Apparatus During Mitral Valve Replacement (판막하부 구조물을 보존하는 인공 승모판막 치환술)

  • 임창영;임정철
    • Journal of Chest Surgery
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    • v.29 no.12
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    • pp.1329-1336
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    • 1996
  • From January, 1994 to January. 1996, mitral valve replacement was performed in 27 patients. Among these, 17 patients underwent mitral valve replacement(MVR) with preservation of the annulo-papillary continuity(PAPCMVR) (-Group I), and 10 patients underwent conventional methods of excision of all the chordae(Group II). The operative technique for PAPCM VR consists of the division of the anterior leaflet into anterior and posterior segments, shifting and reattachment of the divided segments to the mitral ring of the respective commissural areas. This retrospective study has been designed to evalute the postoperative left ventricular function in the two groups. In the group 1, LVEF(Left Vnetricular Ejection Fraction : %) was 52 $\pm$ 3 preoperatively And 50$\pm$3 postoperatively, LVESI Vent icular End Systolic Volume Index/mL/m2) wIns 59 :6 and 51 $\pm$ 7, LVEDI Ventricular End Diastolic Volume Index/mL/m2) was 124$\pm$ 11 and 91 :8. In the group II, LVEF was 56$\pm$1 and 47:), LVESVI 62$\pm$12 and 61$\pm$15, LVEDVI 133$\pm$27 and 104$\pm$17. : the variation of the LVEF in these two group was statistically different(p(0.05). A comparison of left ventricular function data between Group I(n: 17) and Group II(n: 10) revealed better results in echocardiographic LVEF(p<0.05), LVEDVI(p<0.01) in the former group. The mean functional class(UYHA) was 2.6 preoperative and improved to 1.0 postoperatively In group 1, and 2.8 and to 1.0 in group II. We conclude that maintenance of continuity between the mitral annulus and papillary muscles is expected to have a beneficial effect on postoperative left ventricular performance.

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Early Clinical Experience in Aortic Valve Replacement Using On-X$^{circledR}$Prosthetic Heart Valve (On-X$^{circledR}$ 기계판막을 이용한 대동맥판 치환술의 조기 임상 경험)

  • 안병희;전준경;류상완;최용선;김병표;홍성범;박종춘;김상형
    • Journal of Chest Surgery
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    • v.36 no.9
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    • pp.651-658
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    • 2003
  • Since the first implanted in September 1997, the use of On-X prosthetic heart valve has been increasing around in the world. This study was designed to assess the feasibility, safety, and the postoperative hemodynamics with this new valve in clinical setting. Material and Method: The current study was carried out on 52 patients undergoing aortic valve replacement with this prosthesis between April 1999 to August 2002 at Chonnam National University Hospital to evaluate the surgical results. 52% of the patients were male and the average age at implant was 50$\pm$13 years. The study followed the guidelines of the AATS/STS. Preoperatively, 32(61.5%) patients were in NYHA functional class III or IV and 2 patients had previous aortic valve surgery. Concomitant cardiac surgery was performed in 71.1%. The implanted valve sizes were 19 mm in 13 patients, 21 mm in 26, 23 mm in 10 and 25 mm in 3, respectively. Mean follow-up was 16.6$\pm$10.5 months (1∼39 months). Echocardiographic assessment was performed pre- and immediate postoperatively, as well as 3, 6, 12 months after surgery, evaluating pressure loss and regression of left ventricular hypertrophy. Result: Mean cardiopulmonary bypass time was 191$\pm$94.7 minutes with an aortic cross-clamp time of 142$\pm$51.7 minutes. There was no early and late mortality, Freedom from adverse events at 1 year in the study were as follows: thromboembolism, 95.6$\pm$6%; bleeding events, 90.2$\pm$4%; paravalvular leakage 92.3$\pm$4%; and overall valve-related morbidity at 1 year was 76.6$\pm$3%. There were no cases of valve thrombosis, prosthetic valve endocarditis and structural or non-structural failure. Left ventricular function at 12 months after surgery (EF=62.7$\pm$9.8%) revealed a statistically significant improvement compared to preoperative investigation (EF=55.8$\pm$15.9%, p=0.006). Left ventricular mass index was 247.3$\pm$122.3 g/$m^2$ on preoperative echocardiographic study, but regressed to 155.5$\pm$58.2 g/$m^2$ at postoperative 1 year (p=0.002). Over the follow-up period a further decrease of peak transvalvular gradients was observed in all patients: 62.5$\pm$38.0 mmHg on preoperative assessment, 18.2$\pm$6.8 mmHg at immediate postoperative period (p < 0.0001), 7.6$\pm$5.09 mmHg (p<0.0001) at 6 month, 18.0$\pm$10.8 mmHg (p<0.0001) at 1 year. Conclusion: The On-X prosthetic heart valve performs satisfactorily in the first 1 year period. Clinical outcome by examining NYHA functional classification revealed especially good results. Effective regression of left ventricular hypertrophy and statistically significant decrease of transvalvular gradient were observed over the first year, but longer-term follow-up of this patient group is needed to establish the expected rates for late valve-related events as well as the long-term clinical efficacy of this valve.

A Study on Characteristics of Vegetation Distribution according to Revetment Techniques of Riverbank in Han River, Korea (한강 하천제방 호안공법에 따른 식생분포 특성 연구)

  • Kim, Won-Sik;Kwak, Jeong-In;Lee, Kyong-Jae;Han, Bong-Ho
    • Korean Journal of Environment and Ecology
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    • v.25 no.1
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    • pp.17-30
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    • 2011
  • This study has analyzed the vegetation composition in the areas using different slope revetment techniques of riverbanks, in a way to improve the vegetation induction in the future considering the ecological aspects of the induction in Garaeyoul Village, Gangdong-gu, Seoul. The result of the vegetation distribution in each different slope revetment technique was analyzed, that the naturalized herb was dominant in the pole block accounting for 70.7%, while native herb was dominant in the lawn block occupying 48.5% and in the crib block occupying 55.7%. The vegetation coverage measured by different slope revetment techniques was highest in the crib block(average 97.5%), followed by the lawn block(average 95.3%) and pole block(average 27.9%). The vegetation base area was the most wide in the crib block and the most narrowest in the pole block. The result of community analysis in areas using different slope revetment techniques, dry herbs and vine herbs were dominated and the coverage was very poor in the pole block. In the lawn block, the barb was fragmented into narrow areas due to the blocks, which prevented the creation of large-scale plant communities. In the crib block, Miscanthus sacchariflorus, Fescue arundinacea and Aster pilosus, which also consisted of large-scale communities. Average dry weight was also measured by each slope revetment technique. The weight was heaviest in the crib block with $187.63g/m^2$, followed by the lawn block($137.65g/m^2$) and pole block($6.75g/m^2$). The soil moisture contents in the crib block and lawn block was 16.3% and 15.2%, respectively, while that of the pole block was 4.7%, which revealed the highly dry condition of the pole block soil. The analysis result of soil chemical property showed that there was little difference in soil texture, soile acidity(pH), and exchangeable ion content, however, the soil organic matter(OM) content and available $P_2O_5$ were highest in the pole block. In the future, in order to induce more vegetation into river banks and walls, a proper construction method should be applied so that the vegetation area can be expanded as much as possible, considering the safety of the banks.

Determination and Monitoring of Grayanotoxins in Honey Using LC-MS/MS (LC-MS/MS를 이용한 벌꿀 중 grayanotoxin 분석법 연구 및 실태조사)

  • Lee, Sook-Yeon;Choi, Youn-Ju;Lee, Kang-Bong;Cho, Tae-Yong;Kim, Jin-Sook;Son, Young-Wook;Park, Jae-Seok;Im, Sung-Im;Choi, Hee-Jung;Lee, Dong-Ha
    • Korean Journal of Food Science and Technology
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    • v.40 no.1
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    • pp.8-14
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    • 2008
  • This study was performed to establish analysis methods, and evaluated for grayanotoxin in domestic/foreign honey and wild honey. The molecular weight of grayanotoxins I, II and III, excluding grayanotoxin III that has been commercialized, were analyzed by LC-MS/MS. Then, the molecular structure of grayanotoxins I and II were analyzed by NMR. A total 111 samples (25 Korean honey, 21 Korean wild honey, 13 Korean honeycomb honey, 44 foreign honey, 8 foreign wild honey) were examined to determined whether or not each sample contained grayanotoxins I, II, and III. The honey samples were mixed with methanol and loaded into a tC18 cartridge, the filtrate was diluted with water, and the mixture was then analyzed by ESI triple-quadrupole LC-MS/MS. Grayanotoxins were only found in the foreign wild honey and were not detected in Korean honey, Korean honeycomb honey, or Korean wild honey. Three of the samples contained grayanotoxin I, II, and III, and one sample contained only grayanotoxins I and III. The lowest level for grayanotoxin I was 3.13 ${\pm}$ 0.00 mg/kg, and the highest level was 12.93 ${\pm}$ 0.01 mg/kg. The levels of grayanotoxin II were 0.84 ${\pm}$ 0.01 mg/kg, 0.92 ${\pm}$ 0.00 mg/kg and 1.08 ${\pm}$ 0.01 mg/kg, respectively. The lowest level of grayanotoxin III was 0.25 ${\pm}$ 0.01 mg/kg and the highest level was 3.29 ${\pm}$ 0.74 mg/kg. Through this study, safety management for foreign wild honey has been enabled.

Development of New Natural Antioxidants for Cosmeceuticals (천연물 유래 항산화 기능성 화장품 신소재 개발)

  • Yoo, Ick-Dong;Kim, Jong-Pyung;Kim, Won-Gon;Yun, Bong-Sik;Ryoo, In-Ja
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.31 no.4 s.54
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    • pp.349-357
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    • 2005
  • New antioxidative substances for cosmeceuticals were screened from natural resources such as microbial metabolites, mushrooms, and medicinal plants. Four antioxidants were isolated from the fungal metabolite of Eupenicillium shearii and their structures were determined to be new phenolic compounds. The compounds were designated as melanocins A, B, C, and D. Melanocins $A{\sim}D$ exhibited free radical scavenging activity on DPPH and superoxide with $EC_{50}$ values of $21{\sim}94\;and\;7{\sim}84{\mu}M$, respectively, which were stronger activity than those of ${\alpha}-tocopherol$ and BHA. Melanocin A showed anti-wrinkle effects on the UV-irrated hairless mouse skin. A novel hispidin antioxidative compound designated as inoscavin A was isolated from the fruiting body of the mushroom, Inonotus xeranticus. Inoscavin A scavenged superoxide radical with $EC_{50}$ values of $0.03{\mu}g/mL$, and inhibited rat liver microsomal lipid peroxidation with $EC_{50}$ values of $0.3{\mu}g/mL$. Benzastatins $A{\sim}G$, the novel antioxidants isolated from the culture of Streptomyces nitrosporeus showed potent lipid peroxidation inhibitory activity with $EC_{50}$ values of $3{\sim}30{\mu}M$. A cyclopentene compound with strong hypopigmentary effect was isolated from the fungal metabolite of Penicillium sp. and identifed as terrein. Terrein significantly reduced melanin levels in a melanomacyte cell line, Mel-Ab. It showed 10 times stronger activity than kojic acid, but exhibited no cytotoxic effect even in $100{\mu}M$. It was suggested that terrein reduced melanin synthesis by reducing tyrosinase production by MITF down-regulation.

CALPUFF Modeling of Odor/suspended Particulate in the Vicinity of Poultry Farms (축사 주변의 악취 및 부유분진의 CALPUFF 모델링: 계사 중심으로)

  • Lim, Kwang-Hee
    • Korean Chemical Engineering Research
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    • v.57 no.1
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    • pp.90-104
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    • 2019
  • In this study, CALPUFF modeling was performed, using a real surface and upper air meterological data to predict trustworthy modeling-results. Pollutant-releases from windscreen chambers of enclosed poultry farms, P1 and P2, and from a open poultry farm, P3, and their diffusing behavior were modeled by CALPUFF modeling with volume sources as well as by finally-adjusted CALPUFF modeling where a linear velocity of upward-exit gas averaged with the weight of each directional-emitting area was applied as a model-linear velocity ($u^M_y$) at a stack, with point sources. In addition, based upon the scenario of poultry farm-releasing odor and particulate matter (PM) removal efficiencies of 0, 20, 50 and 80% or their corresponding emission rates of 100, 80, 50 and 20%, respectively, CALPUFF modeling was performed and concentrations of odor and PM were predicted at the region as a discrete receptor where civil complaints had been frequently filed. The predicted concentrations of ammonia, hydrogen sulfide, $PM_{2.5}$ and $PM_{10}$ were compared with those required to meet according to the offensive odor control law or the atmospheric environmental law. Subsequently their required removal efficiencies at poultry farms of P1, P2 and P3 were estimated. As a result, a priori assumption that pollutant concentrations at their discrete receptors are reduced by the same fraction as pollutant concentrations at P1, P2 and P3 as volume source or point source, were controlled and reduced, was proven applicable in this study. In case of volume source-adopted CALPUFF modeling, its required removal efficiencies of P1 compared with those of point source-adopted CALPUFF modeling, were predicted similar each other. However, In case of volume source-adopted CALPUFF modeling, its required removal efficiencies of both ammonia and $PM_{10}$ at not only P2 but also P3 were predicted higher than those of point source-adopted CALPUFF modeling. Nonetheless, the volume source-adopted CALPUFF modeling was preferred as a safe approach to resolve civil complaints. Accordingly, the required degrees of pollution prevention against ammonia, hydrogen sulfide, $PM_{2.5}$ and $PM_{10}$ at P1 and P2, were estimated in a proper manner.

Evaluating of the Effectiveness of RTK Surveying Performance Based on Low-cost Multi-Channel GNSS Positioning Modules (다채널 저가 GNSS 측위 모듈기반 RTK 측량의 효용성 평가)

  • Kim, Chi-Hun;Oh, Seong-Jong;Lee, Yong-Chang
    • Journal of Cadastre & Land InformatiX
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    • v.52 no.2
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    • pp.53-65
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    • 2022
  • According to the advancement of the GNSS satellite positioning system, the module of hardware and operation software reflecting accuracy and economical efficiency is implemented in the user sector including the multi-channel GNSS receiver, the multi-frequency external antenna and the mobile app (App) base public positioning analysis software etc., and the multichannel GNSS RTK positioning of the active configuration method (DIY, Do it yourself) is possible according to the purpose of user. Especially, as the infrastructure of multi-GNSS satellite is expanded and the potential of expansion of utilization according to various modules is highlighted, interest in the utilization of multi-channel low-cost GNSS receiver module is gradually increasing. The purpose of this study is to review the multi-channel low-cost GNSS receivers that are appearing in the mass market in various forms and to analyze the utilization plan of the "address information facility investigation project" of the Ministry of Public Administration and Security by constructing the multi-channel low-cost GNSS positioning module based RTK survey system (hereinafter referred to as "multi-channel GNSS RTK module positioning system"). For this purpose, we constructed a low-cost "multi-channel GNSS RTK module positioning system" by combining related modules such as U-blox's F9P chipset, antenna, Ntrip transmission of GNSS observation data and RTK positioning analysis app through smartphone. Kinematic positioning was performed for circular trajectories, and static positioning was performed for address information facilities. The results of comparative analysis with the Static positioning performance of the geodetic receivers were obtained with 5 fixed points in the experimental site, and the good static surveying performance was obtained with the standard deviation of average ±1.2cm. In addition, the results of the test point for the outline of the circular structure in the orthogonal image composed of the drone image analysis and the Kinematic positioning trajectory of the low cost RTK GNSS receiver showed that the trajectory was very close to the standard deviation of average ±2.5cm. Especially, as a result of applying it to address information facilities, it was possible to verify the utility of spatial information construction at low cost compared to expensive commercial geodetic receivers, so it is expected that various utilization of "multi-channel GNSS RTK module positioning system"

A Case Study on the Design of Pickup Truck Tuning Equipment according to the Lifestyle of Modern People (현대인의 라이프스타일에 따른 픽업트럭 튜닝 용품 디자인 사례 연구)

  • Lee, Dong-Hun;Park, Hae-Lim;Lee, Sang-Ki
    • Journal of Service Research and Studies
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    • v.13 no.4
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    • pp.131-141
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    • 2023
  • Changes in consumer needs and behaviors according to lifestyle changes lead to consumption culture, affecting the automobile market. However, research and research to provide options tailored to the lifestyle of consumers in related markets are still insufficient. Focusing on pickup truck accessories applied to pickup trucks that reflect lifestyle the most among vehicle types, this study first examined the theoretical background of the aftermarket market and lifestyle of pickup trucks. Second, through image mapping, the market possibilities and opportunity factors of pickup trucks were discovered through market size analysis and possibilities, and through this, user types could be classified. Third, interviews were conducted with those representing user types, the contents were organized, and interviews were conducted centering on related groups to create a persona of a user group, and what needs each group's persona wanted. Finally, a design concept suitable for the issue keywords and insights derived for each user lifestyle type was presented. In this study, the user type was divided into ① outdoor activity type, ② hobby activity type, and ③ small-scale work type, and a design case study was conducted by applying the concept suitable for the keyword for each group. For the outdoor activity type, a variable storage structure and a living space-type accessory design were presented, and for the hobby type, a modular decktop design and a sports coupe-type hardtop design were presented. For the small business type, a partition that is easy to fix the load and a stepper design that is easy to board the cargo box were presented. It is expected that the size of the pickup truck aftermarket will be expanded by diversifying the option designs that users want by lifestyle by applying them to the development of pickup truck accessories that fit the lifestyle of pickup truck users in the automobile market, which is currently mass customized.

School Dietitians' Perceptions and Intake of Healthy Functional Foods in Jeonbuk Province (전북지역 일부 학교 영양사의 건강기능식품 인식 및 이용실태)

  • Kang, Young-Ja;Jung, Su-Jin;Yang, Ji-Ae;Cha, Youn-Soo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.36 no.9
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    • pp.1172-1181
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    • 2007
  • This research involved 226 Jeonbuk Province school dietitians as subjects to investigate intake and perceptions of the healthy functional foods. Sixty nine percent of the school dietitians didn't even know about the law enforcement concerning the health functional foods. Although 68.1% of the respondents said that they slightly knew about health functional foods, only 25% knew exactly what it was. As shown in the survey, most didn't have the cognitive understanding did not understand which should be obtained by education. Sixty two percent of the answerers said they had experience of taking health various functional food products of various kinds such as supplements (57.9%), red ginseng products (52.9%), and chlorella products (30.0%). The motive of intake was in the order of fatigue restoration (25.7%), sickness prevention (22.9%), and nutrient replenishment (22.9%). A fascinating fact from this study was that the reason for healthy functional product intake was different between groups that was primarily interested in the products and those that was not. For those who had interest, the reason for intake was for sickness prevention. On the other hand, for those who didn't have any interest, the reasons was primarily for fatigue restoration and they were mostly persuaded by close friends and relatives. Main concerns were in the order of side effects (4.72), efficacy after intake (4.59), cleanliness (4.51), reliability of the company (4.29), and price (4.23). In view of the study, it is clear that a lot of people are showing interest in healthy functional food products. However, dietitians who are experts in food and nutrition lacked knowledge and information on healthy functional food.