• 제목/요약/키워드: damage sensitivity

검색결과 500건 처리시간 0.023초

평가인자 가중치에 대한 베이지안 추론과 민감도 분석을 통한 적정 하천설계빈도 결정 (Estimation of the Hydrological Design Frequency of Local Rivers Using Bayesian Inference and a Sensitivity Analysis of Evaluation Factors)

  • 유재희;김지은;이진영;박경운;김태웅
    • 대한토목학회논문집
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    • 제42권5호
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    • pp.617-626
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    • 2022
  • 우리나라는 기상관측 이래 연평균 강수량과 변동성은 점진적으로 증가하는 추세이고, 지역 간 편차가 크다. 또한, 최근의 이상기후로 인하여 재해에 대한 위험도가 증가되고 있는 실정이다. 풍수해의 피해는 주로 하천주변에서 발생하기 때문에 하천기본계획을 수립하기 위해서는 우선적으로 적정한 설계빈도를 결정하는 과정이 반드시 필요하다. 본 연구에서는 설계빈도 결정에 대한 기존 방법론을 분석하여 문제점 및 개선 방향에 대해 제시하였다. 충청남도에 위치한 지방하천 중 자료구축이 가능한 하천인 413개소를 대상으로, 7개의 평가인자(유역면적, 형상계수, 하도경사, 수계차수, 배수영향 구간, 이상강우 발생빈도, 시가화 침수면적)를 선정하고, 베이지안 추론을 통해 가중치를 산정하였다. 그 결과, 이상강우 발생빈도 및 시가화 침수면적의 가중치가 각각 18로 가장 크게 산정되어, 하천 설계빈도 결정에 큰 영향을 미치는 것으로 판단된다. 이러한 가중치를 통해 설계 빈도를 추정한 결과, 기수립 설계빈도보다 본 연구에서 추정된 설계빈도가 증가하는 하천은 255개이고 감소하는 하천은 158개로 나타났다.

어깨 회전근개 파열 진단을 위한 초음파 검사와 자기공명영상 검사의 진단적 유용성 연구 (A Study on the Diagnostic Usefulness of Ultrasound and Magnetic Resonance Imaging for the Diagnosis of Shoulder Rotator Cuff Tear)

  • 강채원;이효영
    • 한국방사선학회논문지
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    • 제16권7호
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    • pp.961-968
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    • 2022
  • 회전근개 파열은 성인 어깨 통증의 주요 원인이다. 사회활동의 증가로 인해 어깨 통증을 호소하는 환자가 증가하고 있으며, 어깨질환에 대한 관심도 높아지고 있다. 초음파 장비의 발달로 진단의 정확도가 높아지면서 근골격계 질환 중에서 회전근개 파열 진단에 주로 이용되면서 초음파검사는 회전근개 파열에서 MRI 검사를 보완할 수 있는 방법으로 인정받고 있다. 따라서 본 연구에서는 어깨 회전근개 파열의 진단에 있어 초음파와 MRI 검사의 진단적 유용성을 알아보고자 하였다. 초음파검사와 MRI검사를 완료한 후 관절내시경검사로 최종 회전근개의 손상을 진단받은 환자 262명을 대상으로 후향적 분석을 하였다. 회전근개중 파열의 빈도가 가장 높은 극상건과 견갑하건 두 힘줄의 초음파검사와 MRI검사의 결과에 대한 민감도, 특이도, 양성예측도, 음성예측도, 정확도를 분석하였다. 또한 회전근개파열의 정도를 5단계로 점수화하여 비교하였다. 초음파 검사는 전층파열과 부분파열 모두 MRI 검사 결과와 유사하였고 통계적으로 유의한 차이는 없었다. 부분파열 검사 결과는 MRI 검사보다 양성예측도와 정확도가 높았다. 결론적으로 초음파는 회전근개 질환을 검사하기 위한 선별검사로 충분히 활용될 수 있으며, 환자의 체질과 상황에 따라 선택하여 임상적으로 활용될 것으로 생각된다.

목포항 해수면 상승에 따른 선박 계류평가요소의 민감도 분석 연구 (A Study on the Sensitivity Analysis of Ship Mooring Evaluation Factors According to Sea Level Rise in Mokpo Port)

  • 김승연
    • 해양환경안전학회지
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    • 제29권5호
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    • pp.445-455
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    • 2023
  • IPCC에서 발표한 제6차 기후변화 보고서에 따르면 지구온난화에 따른 해수면 상승이 가속화되고 있으며, 2100년 예상 해수면 상승은 저탄소 시나리오(SSP 1~2.6)에서는 47cm, 고탄소 시나리오(SSP 5~8.5)에서는 82cm로 분석되었다. 해수면 상승은 항만 인프라에 심각한 피해를 입히고, 항만 내에 정박 중인 선박의 계류안전성을 저하시킬 수 있다. 본 연구에서는 해수면 상승시 부두에 계류한 선박의 계류안전성 향상 방안을 도출하기 위해 만조시 침수 피해가 잦은 목포항을 선정하여 해수면 상승 시나리오에 따른 실제 접안 선박에 대한 계류 평가 요소의 민감도를 분석하였다. 분석 결과, 해수면이 상승함에 따라 동일한 환경조건에서 계류라인 장력, 계선주 하중, 계류라인 수직각도, 선체 6자유도 운동값이 대체로 증가하는 것으로 분석되었다. 또한, 마루높이가 상향되면 모든 계류 평가 요소의 값이 대체로 감소하여 선박 및 부두의 안전성 향상에 유리한 것으로 분석되었다. 본 연구 결과는 목포항 해수면 상승에 따른 항만 및 선박의 안전성 향상 방안을 확보하기 위한 기초자료로 활용될 수 있을 것이다.

기후변화 적응 농경지 토양유실 취약성 평가 (Vulnerability Assessment of Soil Loss in Farm area to Climate Change Adaption)

  • 오영주;김명현;나영은;홍선희;백원기;윤성탁
    • 한국토양비료학회지
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    • 제45권5호
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    • pp.711-716
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    • 2012
  • 기후변화는 100년 후에 남한의 강수량이 17% 증가할 것으로 예측되었다. 우리나라와 같이 여름철 집중호우가 발생하는 경우는 농경지 토양유실이 많아질 것으로 예상된다. 또한 폭풍을 동반한 국지성 호우는 농경지에 많은 피해를 주고 있기 때문에 이에 대한 영향을 최소화하기 위한 적응계획 수립이 시급한 실정이다. 이에 본 연구는 232개 시군구를 대상으로 농경지 토양유실의 취약성 평가를 실시하였다. 취약성 평가의 기간은 현재는 2000년, 미래는 A1B 시나리오를 기준으로 2020년, 2050년, 20100년에 대한 자료를 취합하였다. 취약성을 평가하기 위해 기후노출, 민감도, 적응능력의 대용변수를 선정하였다. 취합된 자료는 표준화 과정을 거쳐 델파이 조사에서 도출된 가중치를 고려하여 취약성을 산정하였다. 취약성은 현재는 남부지방인 제주도와 경상남도가 취약한 것으로 판단되었으나 미래 취약성은 강원도가 증가 추세를 보였다. 본 연구를 통하여 지자체 단위에서 농경지 토양침식에 대한 기후변화 적응계획을 수립하는데 도움이 되고자 한다.

Radiation-induced Apoptosis, Necrosis and G2 Arrest in Fadu and Hep2 Cells

  • Lee Sam-Sun;Kang Beom-Hyun;Choi Hang-Moon;Jeon In-Seong;Heo Min-Suk;Choi Soon-Chul
    • Imaging Science in Dentistry
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    • 제30권4호
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    • pp.275-279
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    • 2000
  • Purpose: Radiation damage is produced and viable cell number is reduced. We need to know the type of cell death by the ionizing radiation and the amount and duration of cell cycle arrest. In this study, we want to identified the main cause of the cellular damage in the oral cancer cells and normal keratinocytes with clinically useful radiation dosage. Materials and Methods: Human gingival tissue specimens obtained from healthy volunteers were used for primary culture of the normal human oral keratinocytes (NHOK). Primary NHOK were prepared from separated epithelial tissue and maintained in keratinocyte growth medium containing 0.15 mM calcium and a supplementary growth factor bullet kit. Fadu and Hep-2 cell lines were obtained from KCLB. Cells were irradiated in a /sup 137/Cs γ-irradiator at the dose of 10 Gy. The dose rate was 5.38 Gy/min. The necrotic cell death was examined with Lactate Dehydrogenase (LDH) activity in the culture medium. Every 4 day after irradiation, LDH activities were read and compared control group. Cell cycle phase distribution and preG1-incidence after radiation were analyzed by flow cytometry using Propidium Iodine staining. Cell cycle analysis were carried out with a FAC Star plus flowcytometry (FACS, Becton Dickinson, USA) and DNA histograms were processed with CELLFIT software (Becton Dickinson, USA). Results: LDH activity increased in all of the experimental cells by the times. This pattern could be seen in the non-irradiated cells, and there was no difference between the non-irradiated cells and irradiated cells. We detected an induction of apoptosis after irradiation with a single dose of 10 Gy. The maximal rate of apoptosis ranged from 4.0% to 8.0% 4 days after irradiation. In all experimental cells, we detected G2/M arrest after irradiation with a single dose of 10 Gy. Yet there were differences in the number of G2/M arrested cells. The maximal rate of the G2/M ranges from 60.0% to 80.0% 24h after irradiation. There is no significant changes on the rate of the G0/G1 phase. Conclusion: Radiation sensitivity was not related with necrosis but cell cycle arrest and apoptosis. These data suggested that more arrested cell is correlated with more apoptosis.

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Antimutagenic Effects of Ginsenoside Rb$_1$, Rg$_1$ in the CHO-K1 Cells by Benzo[a]pyrene with Chromosomal Aberration Test and Comet Assay

  • Kim, Jong-Kyu;Kim, Soo-Jin;Rim, Kyung-Taek;Cho, Hae-Won;Kim, Hyeon-Yeong;Yang, Jeong-Sun
    • Molecular & Cellular Toxicology
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    • 제5권2호
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    • pp.126-132
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    • 2009
  • The usage and types of chemicals are advancing, specializing, large-scaled increasing, and new chemical exposed workers are concerning to occupational disease. The generation of reactive oxygen in the body from carcinogen, mutation and DNA damage in cancer is protected by natural antioxidants (phytochemicals) with antimutagenic effect. There were many reports of ginsenoside Rb$_1$, Rg$_1$ grievances of the genetic mutation to suppress the effect confirm the genetic toxicity test with chromosomal aberration test and the Comet (SCGE) assay confirmed the suppression effect occurring chromosomal DNA damage. We had wanted to evaluate the compatibility and sensitivity between the chromosomal aberration (CA) test and the Comet assay. We used the CA test and Comet assay to evaluate the anti-genotoxicity of ginsenoside Rb$_1$ and Rg$_1$, in CHO-K1 (Chinese hamster ovary fibroblast) cell in vitro, composed negative control (solvent), positive control (benzo[a]pyrene), test group (carcinogen+variety concentration of ginsenoside) group. The positive control was benzo[a]pyrene (50 $\mu$M), well-known carcinogen, and the negative control was the 1 % DMSO solvent. The test group was a variety concentration of ginsenoside Rb$_1$, Rg$_1$ with 10$^{-8}$%, 10$^{-6}$%, 10$^{-4}$%, 10$^{-2}$%, 1%, 10%. In chromo-somal aberration test, we measured the number of cells with abnormally structured chromosome. In Comet assay, the Olive tail moment (OTM) and Tail length (TL) values were measured. The ratio of cell proliferation was increased 8.3% in 10$^{-8}$%, 10$^{-6}$%, 10$^{-4}$%, 10$^{-2}$%, 1%, 10% Rb$_1$ treated groups, and increased 10.4% in 10$^{-10}$%, 10$^{-8}$%, 10$^{-6}$%, 10$^{-4}$%, 10$^{-2}$%, 1% Rg$_1$ treated groups. In the CA test, the number of chromosomal aberration was decreased all the Rb$_1$ and Rg$_1$ treated groups. In the Comet assay, the OTM values were decreased in all the Rb$_1$ and Rg$_1$ treated groups. To evaluate the compatibility between CA and Comet assay, we compared the reducing ratio of chromosomal abnormalities with its OTM values, it was identified the antimutagenicity of ginsenoside, but it was more sensitive the CA test than the Comet assay. Ginsenoside Rb$_1$ and Rg$_1$ significantly decrease the number of cells with chromosomal aberration, and decrease the extent of DNA migration. Therefore, ginsenoside Rb$_1$, Rg$_1$ are thought as an antioxidant phytochemicals to protect mutagenicity. The in vitro Comet assay seems to be less sensitive than the in vitro chromosomal aberration test.

소나무 풍매차대묘의 오존 내성 및 민감성 가계간 생장, SOD 활성 및 MDA 함량 차이 (Difference in Growth, SOD Activity and MDA Content Between Ozone Tolerant and Sensitive Families of Open-Pollinated Pinus densiflora)

  • 이재천;오창영;한심희;김장수
    • 한국산림과학회지
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    • 제95권3호
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    • pp.323-327
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    • 2006
  • 국내 주요 경제수종인 소나무의 내성 가계와 민감성 가계간의 오존에 대한 피해반응 및 내성반응을 알아보고자 본 연구를 수행하였다. 내성 가계와 민감성 가계를 각각 5가계씩 선발하여 오존 100 ppb 농도에서 90일간 처리를 하여 근원경 생장, SOD 활성, MDA 함량을 측정하였다. 근원경 생장에서 오존 처리 초기에 내성 가계가 민감성 가계에 비하여 약 3배 높은 생장율을 보였으며, 처리 기간 동안 내성 가계의 생장이 더 우수한 것으로 나타났다. 대조구에 대한 처리구의 SOD 활성비는 민감성 가계의 경우 오존 처리 초기에 증가하고 처리 기간이 길어짐에 따라서 지속적으로 감소한 반면, 내성 가계는 60일까지 증가한 후 감소하였다. 오존 처리구의 MDA 함량은 대조구에 비하여 전체적으로 높게 나타났으며, 민감성 가계가 내성 가계보다 높은 MDA 함량을 나타냈다. 따라서 내성 가계는 민감성 가계에 비하여 항산화 능력이 우수하기 때문에 지질과산화 작용을 억제하는 등 생리적 장애를 극복하는 능력이 높아 생장감소가 적게 나타나는 것으로 판단된다.

Implications of paraquat and hydrogen peroxide-induced oxidative stress treatments on the GABA shunt pathway in Arabidopsis thaliana calmodulin mutants

  • Al-Quraan, Nisreen A.;Locy, Robert D.;Singh, Narendra K.
    • Plant Biotechnology Reports
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    • 제5권3호
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    • pp.225-234
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    • 2011
  • Arabidopsis mutants with T-DNA insertion in seven calmodulin genes (CAM) were used to determine the specific role of CAM in the tolerance of plants to oxidative stress induced by paraquat and hydrogen peroxide ($H_2O_2$) treatments. Arabidopsis calmodulin mutants (cam) were screened for seedling growth, seed germination, induced oxidative damage, and levels of ${\gamma}$-aminobutyric acid (GABA) shunt metabolites. Only the cam5-4 and cam6-1 mutants exhibited an increased sensitivity to paraquat and $H_2O_2$ during seed germination and seedling growth. In response to treatments with $3{\mu}M$ paraquat and 1 mM $H_2O_2$, only the cam5-4, cam6-1 mutants showed significant changes in malonaldehyde (MDA) levels in root and shoot tissues, with highly increased levels of MDA. In terms of the GABA shunt metabolites, GABA was significantly elevated in root and shoot tissues in response to the paraquat treatments in comparison to alanine and glutamate, while the levels of all shunt metabolites increased in root tissue but not in the shoot tissue following the $H_2O_2$ treatments. GABA, alanine and glutamate levels were significantly increased in root and shoot of the cam1, cam4, cam5-4, and cam6-1 mutants in response to paraquat (0.5, 1 and $3{\mu}M$), while they were increased only in the root tissue of the cam1, cam4, cam5-4, and cam6-1 mutants in response to $H_2O_2$ (200 and $500{\mu}M$, 1 mM). These data show that the cam5-4 and cam6-1 mutants were sensitive to the induced oxidative stress treatments in terms of seed germination, seedling growth, and oxidative damage. The accumulation of GABA shunt metabolites as a consequence of the induced oxidative stress treatments (paraquat and $H_2O_2$ treatments) suggests that the GABA shunt pathway and the accumulation of GABA metabolites may contribute in antioxidant machinery associated with reactive oxygen species and in the acquisition of tolerance in response to induced oxidative stress in Arabidopsis seedlings.

The Beneficial Effects of Ferulic Acid supplementation during In Vitro Maturation of Porcine Oocytes on Their Parthenogenetic Development

  • Lee, Kyung-Mi;Hyun, Sang-Hwan
    • 한국수정란이식학회지
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    • 제32권4호
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    • pp.257-265
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    • 2017
  • Ferulic Acid (FA) is a metabolite of phenylalanine and tyrosine, a phenolic compound commonly found in fruits and vegetables. Several studies have shown that FA has various functions such as antioxidant effect, prevention of cell damage from irradiation, protection from cell damage caused by oxygen deficiency, anti-inflammatory action, anti-aging action, liver protective effect and anti-cancer action. In this study, we investigated the maturation rate, intracellular glutathione (GSH) and reactive oxygen species (ROS) of porcine oocytes by adding FA to the in vitro maturation (IVM) medium and examined subsequent embryonic developmental competence at 5% oxygen through parthenogenesis. There is no significant difference between the control group ($0{\mu}M$) and treatment groups ($5{\mu}M$, $10{\mu}M$, $20{\mu}M$) on maturation rates. Intracellular GSH levels in oocyte treated with $5{\mu}M$ of FA significantly increased (P < 0.05), and $20{\mu}M$ of FA revealed significant decrease (P < 0.05) in intracellular ROS levels compared with the control group. Oocytes treated with FA exhibited significantly higher cleavage rates (79.01% vs 89.19%, 92.20%, 90.89%, respectively) than the control group. Oocytes treated with $10{\mu}M$ showed significantly higher blastocyst formation rates (28.3% vs 40.3%, respectively) after PA than the control group. Total cell numbers in blastocyst of $10{\mu}M$ FA displayed significantly higher (39.4 vs 51.9, respectively) than the control group. In conclusion, these results suggested that treatment with FA during IVM improved the developmental potential of porcine embryos by increasing intracellular GSH synthesis and reducing ROS levels. Also, there was an improvement of cleavage rate, blastocyst formation and total cell numbers in blastocysts. It might be associated with Keap1-Nrf2 pathway as an antioxidant regulate pathway that plays a crucial role in determining the sensitivity of cells to oxidative damages by regulating the basal and inducible expression of enzymes which is related to detoxification and anti-oxidative effects, stress response enzymes and/or proteins and ABC transporters.

($CO_2$)레이저 치료에 의한 치근표면의 구조적 변화 (Strutural Change of Root Surface Following $CO_2$ Laser Treatment)

  • 김도영;한수부;고재승;박성현;계승범;황광세;김우성
    • Journal of Periodontal and Implant Science
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    • 제27권3호
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    • pp.469-478
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    • 1997
  • The purpose of this study was to evaluate the structural change of root surface and the occlusion of dentinal tubule following $CO_2$ laser treatment. Seven extracted healthy human premolar werw curetted, sectioned, and four specimens were randomly assigned to each of 6 different treatment groups : 1) untreated EDTA etched control: 2) root plande only: 3) $CO_2$ laser treated with 2W mode 6(10msec/pulse, 20pps) for 1 minute: 4) $CO_2$ laser treated with 2W mode 6(lOmsec/pulse, 20pps) for 2 minutes: 5) $CO_2$ laser treated with 2W mode 7(20msec/pulse, 20pps) for 1 minute: 6) $CO_2$ laser treated with 2W mode 7(20msec/pulse, 20pps) for 2 minutes. Following the prescribed treatment, the specimens were prepared for SEM evaluation. Results showed that $CO_2$ laser may be effective to occlude dentinal tubules tor dentin sensitivity treatment. The effect of dentinal tubule occlusion was enhanced with increasing the total energy level lased to specimen regardless of lasing mode. The structural changes of root surfaces were restricted to superficies, and these changes included fissuring, charring, crater formation over the smooth lava like texture. The charring and crater formation implying root damage was observed in the case of the longer duration of a pulse. The results of the present study suggests that the pulsed $CO_2$ laser with shorter pulse duration and longer exposure time can be used effectively in order to obtain the optimal dentinal tubule occlusion with minimal root damage.

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