• 제목/요약/키워드: Tail Effect

검색결과 622건 처리시간 0.038초

ANALYSIS OF CHARGE COLLECTION EFFICIENCY FOR A PLANAR CdZnTe DETECTOR

  • Kim, Kyung-O;Kim, Jong-Kyung;Ha, Jang-Ho;Kim, Soon-Young
    • Nuclear Engineering and Technology
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    • 제41권5호
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    • pp.723-728
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    • 2009
  • The response property of the CZT detector ($5{\times}5{\times}5\;mm^3$), widely used in photon spectroscopy, was evaluated by considering the charge collection efficiency, which depends on the interaction position of incident radiation, A quantitative analysis of the energy spectra obtained from the CZT detector was also performed to investigate the tail effect at the low energy side of the full energy peak. The collection efficiency of electrons and holes to the two electrodes (i.e., cathode and anode) was calculated from the Hecht equation, and radiation transport analysis was performed by two Monte Carlo codes, Geant4 and MCNPX. The radiation source was assumed to be 59.5 keV gamma rays emitted from a $^{241}Am$ source into the cathode surface of this detector, and the detector was assumed to be biased to 500 V between the two electrodes. Through the comparison of the results between the Geant4 calculation considering the charge collection efficiency and the ideal case from MCNPX, an pronounced difference of 4 keV was found in the full energy peak position. The tail effect at the low energy side of the full energy peak was confirmed to be caused by the collection efficiency of electrons and holes. In more detail, it was shown that the tail height caused by the charge collection efficiency went up to 1000 times the pulse height in the same energy bin at the calculation without considering the charge collection efficiency. It is, therefore, apparent that research considering the charge collection efficiency is necessary in order to properly analyze the characteristics of CZT detectors.

봉독이 우울증 모델 흰쥐에게 미치는 영향 (Experimental Study on the Anti-depressive Effect of Bee Venom Injection)

  • 이진희;김근우;구병수
    • 동의신경정신과학회지
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    • 제21권2호
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    • pp.61-73
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    • 2010
  • Objectives : The purpose of this study was to assess anti-depressive effects of Bee Venom(BV) on an Animal Model of Depression induced immobility stress. Methods : There was 2 pre-experiments MTT(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and Western blot test and 3 main experiments ; forced swimming test, tail suspension test and Y-maze task. Male rats were used for main experiment. The subject was divided into 4 groups(1. control group injected only saline, without immobility stress 2. Negative group injected saline after 2 hours immobility stress 3. Positive group injected Amitriptyline after 2 hours immobility stress 4. BV group injected Bee Venom after 2 hours immobility stress). Each group consisted of 6 rats. Forced swimming test, tail suspension test, Y-maze task were used to evaluate anti-depressive effect of Bee Venom. Results : In MTT assay, as the density of BV increased, the existence rate of primary neuronal cell increased. In Western blot test, the density of CREB and AKT was increasing as time went by. In forced swimming test, BV group showed immobility decreased more than Normal group and Positive group. In tail suspension test, Normal group and Positive group showed immobility decreased more than BV group. In Y-maze task, BV group showed immobility decreased more than Normal group, but Positive group showed immobility decreased more than BV group. Conclusions : These results suggest that Bee Venom may have anti-depressive effect on depression.

Spinal Co-Administration of Ginsenosides with Morphine Prevents the Development of Opioid Tolerance and Attenuates Opioid Dependence

  • Choi Seok;Jung Se-Yeon;Nah Jin-Ju;Ahn Eun-Soon;Kim Yoon-Hee;Nam Ki-Yeul;Kim Seok-Chang;Ko Sung-Ryong;Rhim Hyewhon;Nah Seung-Yeol
    • Journal of Ginseng Research
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    • 제23권4호
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    • pp.239-246
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    • 1999
  • 백서를 이용하여 진세노사이드 흑은 모르핀을 척수강내 투여한 다음 tail-flick test를 통하여 진통 작용을 연구하였다. 또한, 진세노사이드를 모르핀과 함께 척수강내 장기 처리할 경우 모르핀에 의한 내성 및 의존성 유발에 미치는 영향을 연구하였다. 연구 결과, 척수강내 진세노사이드의 투여는 200 ${\mu}g$/rat에서 약한 진통 작용이 있는 것으로 나타났다. 모르핀은 투여 농도에 의존적으로 좋은 진통 효능을 보여주었으며, $ED_50$은 1.2 ${\mu}g/rat$인 것으로 나타났다. 그러나 진세노사이드의 모르핀을 함께 척수강내 투여할 경우 모르핀의 진통 작용을 증가 시키지 않은 것으로 나타났다. 200 ug/rat 진세노사이드를 10 ${\mu}g$/rat모르핀을 7일 동안 같이 투여할 경우 모르핀에 의한 통증 작용에 대한 내성을 억제하였으며, 모르핀에 의한 의존성을 부분적으로 억제하는 것으로 나타났다. 이러한 연구 결과는 척수 수준에서 진세노사이드가 모르핀의 장기 투여에 의하여 유도되는 모르핀에 대한 내성 및 의존성을 억제하는 것으로 사료된다.

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홍미삼 에탄올 추출분획의 항산화 활성 (Antioxidative Activity of Ethanol Extraction Fraction from the Korean Red Tail Ginseng)

  • 이종원;도재호
    • 한국식품과학회지
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    • 제33권4호
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    • pp.497-500
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    • 2001
  • 본 연구의 목적은 홍미삼의 기능성 연구의 일환으로 총 페놀성 화합물의 추출방법과 DPPH에 대한 수소공여능, linoleic acid의 산화방지활성 및 LDL에 의한 항산화활성 등을 중심으로 연구한 결과이다. 홍미삼에 60% 에탄올를 첨가하여 추출회수별 총 페놀성 화합물을 조사한 결과 3회까지 추출했을 때 대부분이 추출되었기 때문에 추출횟수는 3회가 적당한 것으로 판단되었다. 60% 에탄올 추출액의 수율은 3회까지 추출했을 때 약 37.35%가 추출되었다. 추출 용매에 따른 총 페놀성 화합물의 추출 효율은 물 추출구를 100%로 했을 때, 60% 에탄올 용액으로 추출한 뒤 농축하여 물로 부피를 재조정한 시험구는 122%로 조사되었다. 항산화활성 조사에서 DPPH에 대한 수소공여능에서 시간이 경과함에 따라 항산화 활성이 약간씩 증가하나 활성은 약한 편이었다. Linoliec acid 산화에 대한 산화억제 효과는 1,500 ppm 농도에서 약 72.23%의 저해율을 나타났으며, LDL에 대한 산화방지 효과는 250 ppm 농도에서 그 저해율이 약 22.52%로 나타났다.

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한국형 기동헬기 꼬리 날개 디페인팅 현상을 통한 도장 품질 향상에 관한 연구 (A study on improvement of painting quality through a de-painting phenomenon of KUH-1 tail blade)

  • 장인기;김영진;서현수;전부일
    • 품질경영학회지
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    • 제42권3호
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    • pp.325-338
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    • 2014
  • Purpose: The purpose of this study was to explain de-painting phenomenon of KUH-1 tail blade and to propose useful solution of it by test. The proposed solution was evaluated by real flight, and then it applied to mass product to improve the paint qual ity of KUH-1 tail blade. Methods: This study investigated an adhesive ability of primer following surface sanding condition. The cross cut and scratch test were conducted to evaluate the adhesive strength. And the water flow test was designed to simulate a real flight condition under rain. Through water flow test, an optimal condition of tail blade to prevent a de-painting phenomenon was deduced. Finally, the improvement method was evaluated by real flight under rain. Results: The results of this study are as follows; The sequential polishing was most excellent method in primer painting quality. The results of test including cross cut, scratch and water flow showed that MIL-DTL-53039 paint with epoxy primer has excellent adhesive ability. To proof the effect of improvement, a real flight during a rain condition was conducted. Finally, the comparison between original and improved configuration was conducted. Conclusion: The painting quality of KUH-1 tail blade was improved through deriving an optimal painting condition. In detail, a condition of optimal sanding and a sort of primer and paint was showed. Finally, the reliability of tail blade was guaranteed through improving the quality of painting.

The Analgesic Effect of Bee Venom Acupuncture and Its Mechanism on the Type II Collagen-Induced Arthritis Rats

  • Seo, Byung-Kwan;Baek, Yong-Hyun;Choi, Do-Young;Park, Dong-Suk
    • Journal of Acupuncture Research
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    • 제22권2호
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    • pp.19-32
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    • 2005
  • Objectives : to evaluate the analgesic effect of bee venom acupuncture on Choksamni (ST36) in the collagen-induced arthritis rats and investigate the role played by serotonergic receptor subtypes (5-HT1a, 5-HT2a) in the antinociceptive effect of bee venom acupuncture in a thermal hyperalgesia test Methods : Experiments were performed on 5 week-aged 60 male Sprague-Dawley rats according to National Institute of Health guidelines and the ethical guidelines of the International Association for the Study of Pain (IASP). Arthritis was induced with arthrogenic collagen emulsion (Bovine type II collagen ${\mu}g$ with incomplete Freund's adjuvant $100\;{\mu}g$). The onset of arthritis was considered to be present when erythema and swelling were detected in at least one joint. The thermal hyperalgesia was evaluated weekly with tail flick test in the rats of severity grade 3 without any injury at tail and foot (including inflammation, ulceration, snap). In the fourth week after first immunization, the analgesic effect of bee venom acupuncture (Choksamni, ST36) was measured with consecutive tail flick latency after intraperitoneal injection of spiroxatrine (1mg/kg) and spiperone (1mg/kg). Results : Chronic inflammatory pain was induced as time elapsed after the immunization of arthrogenic collagen and the maximum value was reached from third to fifth week. Chronic inflammatory pain induced by CIA was inhibited by bee venom acupuncture on the left ST36. The analgesic effect of bee venom acupuncture was inhibited by intraperitoneal injection of 5-HT1a antagonist spiroxatrine and 5-HT2a antagonist spiperone. Conclusions : Therefore, a conclusion. that the analgesic effect of bee venom acupuncture in the chronic inflammatory pain is partially mediated by 5-HT1a and 5-HT2a receptors can be made.

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Inverted Staggered-Type 비정질 실리콘 박막트랜지스터의 수치적 분석 (Numerical Analysis of Inverted Staggered-Type Hydrogenated Amorphous Silicon Thin Film Transistor)

  • 오창호;박진석;한민구
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1990년도 추계학술대회 논문집 학회본부
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    • pp.93-96
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    • 1990
  • The characteristics of an inverted staggered-type hydrogenated amorphous silicon thin film transistor has been analyzed by employing numerical simulation. The field effect mobility and threshold voltage are characterized as a function of density of deep and tail states and lattice temperature. It has been found that the density of deep states plays an important role of determining the threshold voltage, while the field effect mobility are very sensitive to the slope of band tail states. Also, the numerically temperature dependence of field effect mobility and threshold voltage has been in good agreements with the experimental results.

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Suppressive Effects of Propolis in Rat Adjuvant Arthritis

  • Park, Eun-Hee;Kahng, Ja-Hoon
    • Archives of Pharmacal Research
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    • 제22권6호
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    • pp.554-558
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    • 1999
  • The effects of ethanolic extract (EEP) of propolis on chronic inflammation were evaluated using rat adjuvant arthritis. In the chronic inflammatory animal model, the arthritis index was suppressed by EEP treatments (50 mg/kg/day and 100 gm/kg/day, p.o.). Moreover, physical weakness, induced by the chronic disease state, was dose-dependently improved in the EEP-treated groups. It s analgesic effect, assessed using the tail-flick test, was comparable to prednisolone (2.5 mg/kg/day, p.o.) and acetyl salicylic acid (100 mg/kg/day, p.o.). In carrageenan rat hind paw edema, which was conducted to test the effects of subfractions of EEP, the petroleum ether sub-fraction (100 mg/kg, p.o.) showed an inhibitor effect on the paw edema whereas EEP (200 mg/kg, p.o.) showed a significant anti-inflammatory effect at 3 and 4 hrs after carrageenan injection. From these results, we conclude that the ethanolic extract of propolis had a profound anti-inflammatory effects on both chronic and acute inflammations.

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고출력 마이크로파 펄스의 대기권 전파시 방전 및 주파수 스펙트럼에 관한 특성 (Characteristics on the Breakdown and Frequency Spectrum of High Power Microwave Pulse Propagating through the Atmosphere)

  • 김영주
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제48권8호
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    • pp.591-597
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    • 1999
  • The propagation characteristics of high power microwave pulse in an air-breakdown environment are examined. The maximum electron density produced by microwave air-breakdown is limited to $10^6cm^{-3}$ by the tail-erosion effect. Inorder to increase the electron density, the scheme using two pulses intersecting at a desired height is considered. Increasing the carrier frequency, it is shown that microwave pulse can be transferred without the serious erosion in the numerical simulation. This result is useful for the above scheme. Also, an experiment is conducted to show the tail-erosion effect and confirm that a rapidly generated lossy plasma can cause spectral breaking and frequency shift of a high-power microwave pulse. The experimental results are presented by comparing the frequency spectrum of an incident pulse with that of the pulse transmitted through a self-induced air-breakdown environment. The experimental results show that the amount of frequency upshift is co-related with the ionization rate, whereas that of frequency downshift is correlated with the energy losses from the pulse in the self-generated plasma.

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Anti-nociceptive and Anti-inflammatory Effect of an Ethanol Extract of The Leaf and Stem of Aralia cordata

  • Jang, Ji Yeon;Seong, Yeon Hee
    • Natural Product Sciences
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    • 제20권4호
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    • pp.301-305
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    • 2014
  • The aim of our study is to investigate the anti-nociceptive and anti-inflammatory properties of an ethanol extract of the leaf and stem of Aralia cordata. Writhing responses induced by acetic acid, tail immersion test, and formalin-induced paw pain response for nociception and formalin-induced paw edema for inflammation were evaluated in mice. A. cordata (50 - 200 mg/kg, p.o.) and ibuprofen (100 mg/kg, p.o.), a positive non-steroidal anti-inflammatory drugs (NSAIDs), inhibited the acetic acid-induced writhing response, but they did not protect the thermal nociception in tail immersion test. However, morphine (5 mg/kg, s.c.) used as positive opioid control alleviated both the acetic acid-induced writhing response and thermal nociception in tail immersion test. In the formalin test, A. cordata (50 - 200mg/kg) and ibuprofen (200mg/kg) inhibited the second phase response (peripheral inflammatory response), but not the first phase response (central response), whereas morphine inhibited both phase pain responses. Both A. cordata (100 mg/kg) and ibuprofen (200 mg/kg) significantly alleviated the formalin-induced increase of paw thickness, the index of inflammation. These results show for the first time that the leaf and stem of A. cordata has a significant anti-nociceptive effect that seems to be peripheral, but not central. A. cordata also displays an anti-inflammatory activity in an acute inflammation model. The present study supports a possible use of the leaf and stem of A. cordata to treat pain and inflammation.