• 제목/요약/키워드: dose response

검색결과 2,332건 처리시간 0.039초

Robot Techologies in Response to Accidents in Nuclear Power Plants

  • Kim, Seungho;Jung, Kyung-Min;Kim, Chang-Hoi;Seo, Yong-Chil
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2002년도 ICCAS
    • /
    • pp.43.6-43
    • /
    • 2002
  • $\textbullet$ KAEROT/m1 with an omni-directional planetary wheel mechanism for the narrow corridor. $\textbullet$ KAEROT/m2 can pass over the ditch with specially designed four wheel of a re-configurable crawler. $\textbullet$ Stereo imaging system with master manipulator enhancing the tele-presence. $\textbullet$ Small hybrid dosimeter detecting radiation dose and dose rate simultaneously.

  • PDF

Individual-Based Models Applied to Species Abundance Patterns in Benthic Macroinvertebrate Communities in Streams in Response to Pollution

  • Cho, Woon-Seok;Nguyen, Tuyen Van;Chon, Tae-Soo
    • 생태와환경
    • /
    • 제45권4호
    • /
    • pp.420-443
    • /
    • 2012
  • An Individual-Based Model (IBM) was developed by employing natural and toxic survival rates of individuals to elucidate the community responses of benthic macroin-vertebrates to anthropogenic disturbance in the streams. Experimental models (dose-response and relative sensitivity) and mathematical models (power law and negative exponential distribution) were applied to determinate the individual survival rates due to acute toxicity in stressful conditions. A power law was additionally used to present the natural survival rate. Life events, covering movement, exposure to contaminants, death and reproduction, were simulated in the IBM at the individual level in small (1 m) and short (1 week) scales to produce species abundance distributions (SADs) at the community level in large (5 km) and long (1~2 years) scales. Consequently, the SADs, such as geometric series, log-series, and log-normal distribution, were accordingly observed at severely (Biological Monitoring Working Party (BMWP<10), intermediately (BMWP<40) and weakly (BMWP${\geq}50$) polluted sites. The results from a power law and negative exponential distribution were suitably fitted to the field data across the different levels of pollution, according to the Kolmogorov-Smirnov test. The IBMs incorporating natural and toxic survival rates in individuals were useful for presenting community responses to disturbances and could be utilized as an integrative tool to elucidate community establishment processes in benthic macroin-vertebrates in the streams.

The Effect of Rheum palmatum L. and Rheum undulatum L. on Rat Thoracic Aorta and Abdominal Aorta

  • Kim, Tack;Kim, Hyung-Hwan;Ahn, Duk-Kyun;Choi, Ho-Young
    • 대한한의학회지
    • /
    • 제24권4호
    • /
    • pp.87-91
    • /
    • 2003
  • Objectives: To examine the relaxational response to the water extract of Rheum palmatum L. and Rheum undulatum L. on rat thoracic aorta and abdominal aorta. Methods: Segments of thoracic aorta and abdominal aorta obtained from rats immediately after delivery were mounted in organ baths superfused on a polygraph. Results : We found that the thoracic aorta segments responded to the water extract of genus Rheum with a dose-dependent vasorelaxation. At $10^{-4}$ M 5-HT, the maximal contraction force was 93.5% of the maximum KCI-response. The 5-HT induced contractions at $10^{-4}$ M were inhibited by 86.4% and 62.1 % after addition of the high concentrations of R. palmatum root (RPR) and leaf (RPL) and R. undulatum root (RUR) and leaf (RUL). At 10 mg/ml RPR and RUR, the relaxational response at thoracic aorta and abdominal aorta with and without endothelium were 86.4%, 83.2%, 85.8%, and 62.1% of the maximum 5-HT induced contraction. Conclusion: Our result showed that RPL and RUL induced dose-dependent vasorelaxation on rat thoracic aorta and abdominal aorta, and that RPL and RUL roots have more potent effects than the leaves.

  • PDF

Reversal of Immunogenicity in Pediatric Inflammatory Bowel Disease Patients Receiving Anti-Tumor Necrosis Factor Medications

  • Kang, Elise;Khalili, Ali;Splawski, Judy;Sferra, Thomas J.;Moses, Jonathan
    • Pediatric Gastroenterology, Hepatology & Nutrition
    • /
    • 제21권4호
    • /
    • pp.329-335
    • /
    • 2018
  • Loss of response to anti-tumor necrosis factor (anti-TNF) agents in the treatment of inflammatory bowel disease (IBD) is a major consideration to maintain sustained response. Reversal of immunogenicity can re-establish response and increase the durability of these agents. Strategies to reverse immunogenicity include dose-intensification and/or the addition of an immunomodulator. However, there is a relative paucity of data on the efficacy of such interventions in pediatric IBD patients. Available reports have not strictly utilized homogenous mobility shift assay, which reports on anti-drug antibodies even in the presence of detectable drug, whereas prior studies have been confounded by the use of drug sensitive assays. We report four pediatric inflammatory bowel disease patients with successful reversal of immunogenicity on an anti-TNF agent using dose intensification and/or addition of an immunomodulator.

Energy Response in Chemiluminescence Dosimetry with Sugar and Sorbite

  • Jun, J.S.;Guggenberger, R.;Dalheimer, A.
    • Nuclear Engineering and Technology
    • /
    • 제33권6호
    • /
    • pp.626-637
    • /
    • 2001
  • A series of study on energy dependence in chemiluminescence dosimetry with sugar and sorbite produced in two different countries was carried out administering a dose of 5 Gy to the samples at six different mean photon energies of 30, 50, 80, 130, 662 and 1250 keV. The results revealed distinct energy dependence of chemiluminescence(CL) output of sugar and sorbite. Although the energy dependence, in general, could be fitted by a polynomial of (os E, with I being radiation energy, up to cubic term, we reached a conclusion that the adoption of a fitting function, $y_{R}$$^{=a}$.(1-e $^{-b.logE}$)$^{c}$ +d, deduced from theoretical energy response curve calculated as the ratio of the mass energy absorption of the samples of interest to the soft tissue is more reasonable and rational. Herecoefficients $y_{R}$ is CL intensity, and a, b, c and d are constants to be determined in the fitting process. Energy dependence of relative sensitivities of one sample to the other, discrepancy in sensitivities of the samples from the two countries, and prominent grain size effect in Sorbitol were also shown.shown.

  • PDF

Do neonicotinoid insecticides impaired olfactory learning behavior in Apis mellifera?

  • Imran, Muhammad;Sheikh, Umer Ayyaz Aslam;Nasir, Muhammad;Ghaffar, Muhammad Abdul;Tamkeen, Ansa;Iqbal, Muhammad Aamir
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • 제38권1호
    • /
    • pp.1-5
    • /
    • 2019
  • Bee's population is declining and disappearing at alarming rate. There are many factors responsible for declining the population of bees including diseases, natural enemies, environmental conditions and pesticides. Insecticides play its role dramatically for their population decline and neonicotinoid insecticides are critically important due to their wide application for pest control. Keeping in view of above problem, effect of neonicotinoid insecticides on olfactory learning behavior in Apis mellifera was observed using Proboscis Extension Reflex (PER) method. In this method, bees were harnessed in centrifuges tubes and feed on insecticides mixed sugar solution after three hours hunger. Bees were checked by feeding on non-treated sugar solution to observe PER response. Minimum proboscis extension was observed for acetamiprid and imidacloprid with 26% and 20% respectively at their recommend field doses while it was maximum for dinotefuran and thiamethoxam with 73% and 60% respectively. Only 40% bees showed response when exposed at 1/10 concentration of field dose for imidacloprid and the least at 1/100 of field dose. At control (Sugar solution) about 90% bees showed PER response. Among these neonicotinoid insecticides tested, imidacloprid and acetamiprid were the most damaging which impaired the olfactory learning performance in Apis mellifera.

물리학 선량법을 이용한 갑상선암의 개인별 최대안전용량 I-131 치료법 개발과 유용성 평가 (Development and Assessment Individual Maximum Permissible Dose Method of I-131 Therapy in High Risk Patients with Differentiated Papillary Thyroid Cancer)

  • 김정철;윤정한;범희승;제갈영종;송호천;민정중;정환정;김성민;허영준;이명호;박영규;정준기
    • 대한핵의학회지
    • /
    • 제37권2호
    • /
    • pp.110-119
    • /
    • 2003
  • 목적: 분화갑상선암 환자에 대한 방사성옥소(I-131) 치료는 재발율과 사망률을 감소시키는 효과적인 치료법이지만, 치료용량을 증가시킴으로써 치료율을 향상시킬 수 있는지에 대해서는 아직 논란이 있다. 본 연구에서는 최대허용선량 치료법의 효용성을 검증하고자 하였다. 대상 및 방법: 임상적 병기가 제3, 4병기이고, 6개월 이후에 I-131 전신스캔(이하 IWBS)과 혈중 thyroglobulin (이하 Tg), anti-thyroglobulin antibody (이하 ATA), 초음파검사(이하 US) 및 F-18 FDG PET 등을 통해 치료여부를 확인할 수 있었던 58명(남:여=9:49, 평균연령 $50{\pm}11$세)의 유두상갑상선암 환자를 대상으로 하였다. 이중 11명은 제4병기, 47명은 제3병기였으며, 43명(남:여=4:39, 평균연령 $50{\pm}11$세)은 7.4 GBq 이하의 고식적인 저용량치료법으로 치료하였고, 9.25 GBq 이상의 고용량 치료를 받은 환자는 15명(남:여=5:10, 평균연령 $50{\pm}12$세)으로 고용량군에서 남자가 더 많았으나 연령의 차이는 없었다. 고용량군 환자 모두에서 추적용량의 방사성옥소(평균 $77{\pm}3MBq$)를 경구 투여한 후 혈중 방사능소실곡선을 통해 최대허용선량(maximum permissible dose, 이하 MPD)을 계산하였으며, 7명에서는 말초혈액림프구의 중기염색 체분석법에 의해 생물학적으로 MPD를 계산하였다. 14명에서는 치료용량의 방사성옥소를 투여한 후 혈중 방사능소실곡선을 통해 MPD를 계산하였다. 완전치유(complete response, 이하 CR)는 IWBS에서 병소가 없어지고, 혈중 Tg치가 1 ng/mL 이하로 감소한 경우로 정의하였으며, 부분치유(partial response, 이하 PR)는 IWBS에서 병소가 없어졌더라도 혈중 Tg, ATA치가 높거나, US 또는 PET 검사에서 병소가 남아있는 경우로 정의하였다. 치료후 IWBS에서 병소가 오히려 증가하거나 변함없는 경우는 없었다. 방사성옥소 치료에 의한 부작용은 입원기간 중 타액선이 현저하게 붓고 통증이 있거나, 구토를 심하게 하는 경우, 그리고 퇴원후 1개월째 백혈구수가 20% 이상 감소한 경우로 정의하였다. 결과: 양 군간에 연속적인 수치변화를 비교하는 경우는 paired t-test를 이용하였으며, 대상군간 치료효과와 부작용의 비교는 chi-square test를 이용하였다. p값 0.05 미만을 통계적으로 유의한 차이로 인정하였다. 고용량군 환자 모두에서 추적용량과 치료용량의 방사성옥소 투여 후 혈액의 피폭선량은 각각 $0.012{\pm}0.3Gy,\;1.66{\pm}25Gy$였으며, 방사성옥소 투여 후 혈액에 전달되는 피폭선량은 추적용량보다 치료용량에서 더 많았고(1.21: 166 rad, p<0.0001), 방사성옥소 1 mCi당 혈액에 전달되는 피폭선량은 차이가 없었다($0.58{\pm}0.1\;vs.\;0.56{\pm}0.1$ rad/37 MBq, p=0.34). 추적용량 방사성옥소 투여 후 구한 MPD는 평균 $13.3{\pm}1.9GBq\;(9.7{\sim}16GBq)$ 이였고, 치료용량 방사성옥소 투여 후 구한 MPD는 평균 $13.8{\pm}2.1GBq(10.4{\sim}16.3GBq)$로 유의한 차이가 얻었으며 (p=0.20), 두 수치간에는 유의한 상관 관계가 있었다(r=0.8, p<0.0001). 7명의 환자에서 말초혈액림프구 중기염색체 분석법으로 MPD를 측정하였는데 혈액의 피폭선량은 $1.78{\pm}0.03Gy$였으며, 같은 환자에서 혈중 방사능소실곡선으로부터 구한 피폭선량은 $1.54{\pm}0.03Gy$로 유의하게 낮았으나 (p=0.01), 두 측 정치 간에는 유의한 상관관계(r=0.86, p=0.01)가 있었다. 저용량 치료군 43명 중 22명(51.2%)에서 완전치유를 보였고 21명(48.8%)에서는 부분치유를 보인 반면, 고용량 치료군 15명 중 12명(80%)에서 완전치유를 보였고 3명(20%)에서만 부분치유를 보여 고용량 치료군에서 유의하게 높은 완전치유를 얻을 수 있었다(p=0.05). 한편 부작용 발생빈도는 저용량 치료군 43명 중 13명(30.2%), 고용량 치료군 15명중 6명(40%)로 양군간에 유의한 차이가 없었다(p=0.46). 임상적인 병기, 연령 및 성별에 따라서는 치유의 차이가 없었다(모두 p>0.05). 결론: 혈중소실곡선으로부터 MPD를 결정하고 이를 토대로 환자 개개인별로 적절한 선량을 선택하여 치료하는 방법은 부작용을 최소화하면서도 치료효과를 높일 수 있는 매우 유용한 치료법이며, 고위험군 분화갑상선 암 환자에게 가장 적절한 치료법이라고 사료되었다.