• Title/Summary/Keyword: Tail Effect

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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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    • v.41 no.5
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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.

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

  • Lee, Jin-Hee;Kim, Geun-Woo;Koo, Byung-Soo
    • Journal of Oriental Neuropsychiatry
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    • v.21 no.2
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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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    • v.23 no.4
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    • pp.239-246
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    • 1999
  • The analgesic effect of ginsenosides or morphine was determined following intrathecal (i.t.) administration in rat tail-flick test. The effects of intrathecal co-administration of ginsenosides with morphine on the development of opioid tolerance and dependence were also examined using rat tail-flick test and naloxone-pre-cipitated withdrawal, respectively. Administration of ginsenosides (i.t.) produced a weak antinociception in a dose-dependent manner. Administration of morphine (i.t.) also produced antinociception in a dose-dependent manner. The $ED_50$ was $1.20\;{\mu}g\;(1.14\~1.29\;{\mu}g)$. However, the acute co-administration of $200{\mu}g$ ginsenosides with 0.1-1.0${\mu}g$ morphine did not show additive effect on morphine induced analgesia in rat tail-flick test. I.t. co-administration of 200 ${\mu}g$ ginsenosides with 10 ${\mu}g$ morphine for 7 days inhibited development of tolerance induced by 10 ${\mu}g$ morphine in rat tail-flick test, although i.t. co-administration of 50 or 100 ${\mu}g$ ginsenosides with morphine was without effect. I.t. co-administration of 200 ${\mu}g$ ginsenosides for 7 days also partially attenuated the development of morphine dependence as assessed by naloxone-precipitated withdrawal. In conclusion, these results suggest that i.t. administered ginsenosides produce a weak antinociception in rat tail-flick test and also prevent opioid tolerance and attenuate opioid dependence in chronic treatment with morphine at the spinal sites.

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

  • Lee, Jong-Won;Do, Jae-Ho
    • Korean Journal of Food Science and Technology
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    • v.33 no.4
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    • pp.497-500
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    • 2001
  • The purpose of this study was to investigate the extraction method and antioxidative activities of phenolic compounds from Korean red tail ginseng. Antioxidative activities of red tail ginseng were evaluated with its ability to donate hydrogen to DPPH, and to inhibit the oxidation of linoleic acid and LDL induced by $H_2O_2$ and $FeCl_2$, respectivly by measuring the MDA formation. Total phenolic compounds expressed as % caffeic acid were 0.80%, 0.12%, 0.06%, 0.03%, 0.01% when red tail ginseng was consecutively extracted with 60% ethanol for 5 times, most of the phenolic compounds was recovered in the extract obtained after 3 times of extraction. The extraction efficacy of 60% ethanol was superior to that of water in extraction phenolic compounds, and the efficacy did not change after evaporating the extract followed by dissolving with water. 60% ethanol extract of red tail ginseng had weak ability to donate hydrogen to DPPH. MDA determination showed the antioxidative effect with inhibition ratio of 72.23% on linoleic acid oxidation by addition of red tail ginseng extract at the concentration of 1,500 ppm. 22.52% of LDL oxidation was inhibited by addition of 250 ppm.

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

  • Chang, In-Ki;Kim, Young-Jin;Seo, Hyun-Soo;Jeon, Boo-Il
    • Journal of Korean Society for Quality Management
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    • v.42 no.3
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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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    • v.22 no.2
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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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Effects of Wheel Profile on KTX Dynamic Characteristics (차륜답면 형상변화에 따른 KTX의 동특성)

  • 장종기;이승일;최연선
    • Journal of the Korean Society for Railway
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    • v.7 no.3
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    • pp.259-263
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    • 2004
  • The running safety of a railway vehicle depends on the design parameters and contact condition between wheel and rail. In this study, the effect of the conicity of wheel tread is analyzed using ADAMS/RAIL software on running situation. Modal analysis shows in 0.6 Hz natural frequency of lateral mode in fully arranged the KTX cars. The excessive vibration of the tail cars occurs in the 17th car as the speed and the stiffness of the secondary suspension increases, and especially for 1/40 conicity of the GV40 wheel. Also, the analysis shows that combination of wheel profile, GV40 for power cars and XP55 for passenger cars can reduce the lateral vibration of the tail cars.

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

  • Kim, Yeong-Ju
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.48 no.8
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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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    • v.20 no.4
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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.

A Study on Refresh Time Improvement of DRAM using the MEDICI Simulator (MEDICI 시뮬레이터를 이용한 DRAM의 Refresh 시간 개선에 관한 연구)

  • 이용희;이천희
    • Journal of the Korea Society for Simulation
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    • v.9 no.4
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    • pp.51-58
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    • 2000
  • The control of the data retention time is a main issue for realizing future high density dynamic random access memory. The novel junction process scheme in sub-micron DRAM cell with STI(Shallow Trench Isolation) has been investigated to improve the tail component in the retention time distribution which is of great importance in DRAM characteristics. In this' paper, we propose the new implantation scheme by gate-related ion beam shadowing effect and buffer-enhanced ${\Delta}Rp$ (projected standard deviation) increase using buffered N-implantation with tilt and 4X(4 times)-rotation that is designed on the basis of the local-field-enhancement model of the tail component. We report an excellent tail improvement of the retention time distribution attributed to the reduction of electric field across the cell junction due to the redistribution of N-concentration which is Intentionally caused by ion Beam Shadowing and Buffering Effect using tilt implantation with 4X-rotation. And also, we suggest the least requirements for adoption of this new implantation scheme and the method to optimize the key parameters such as tilt angle, rotation number, Rp compensation and Nd/Na ratio. We used MEDICI Simulator to confirm the junction device characteristics. And measured the refresh time using the ADVAN Probe tester.

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