• Title/Summary/Keyword: Physical dependence

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Study on rock reinforcement process and the effect of produced strength right after rockbolt installation (록볼트의 타설 직후의 강도발현 과정 및 효과에 관한 연구)

  • Itoh, Jhun;Park, Hae-Geun;Kim, Dong-Wan;Kim, Jea-Kwon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.5 no.2
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    • pp.189-198
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    • 2003
  • For the huge section of tunnel, it is highly required to observe the role of each rock support and their effect of rock reinforcement in order to investigate more reasonable rock support structure. Especially for unstable tunnel situation with no shotcrete strength right after an excavation, sufficient investigation is needed for rock support structure. In this paper, we clarify the relations of compressive strength and material age, cohesion strength and material age, and cohesion stiffness and material age of grout with time-dependence through tests and numerical analysis simulation with trial rock mass considering hardening of bolt grouting material. By means of this process, effect of rock reinforcement for rockbolt is investigated right after an excavation and modelling and physical constants of young aged rockbolts are obtained. Additionally, the effect of rock reinforcement with hydraulic tensile friction bolt is examined right after an excavation, which grout effect is no need to be waited.

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Effect of High Pressure on Polarographic Parameters of Metal Complex Ion (金屬錯이온의 폴라로그래피的 파라미터에 미치는 壓力의 影響)

  • Heung Lark Lee;Zun Ung Bae;Jong Hoon Yun
    • Journal of the Korean Chemical Society
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    • v.31 no.5
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    • pp.444-451
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    • 1987
  • The dependence of polarographic parameters on the pressure for the reduction of copper(II), cadmium(II), and zinc(II) complex ions with ethylenediamine, propylenediamine, and diethylenetriamine has been studied. In this study the dropping mercury electrode, the mercury pool electrode, and helix type of platinum wire were used as the working, the reference, and the auxilary electrode, respectively. With increasing the pressure from 1 atmosphere to 1,500 atmospheres, the reduction half-wave potentials of metal complex ions are shifted to the negative values and the diffusion currents become considerably larger, in keeping with the theory on the change of the physical properties of the electrolytic solution such as the density, the viscosity, the dielectric constant, and the electrical conductance, etc. The slope values of the logarithmic plot are increased with increasing the pressure, which indicates the more irreversible reduction. The temperature coefficients of diffusion current observed over the range of the temperature from 25$^{\circ}$C to 35$^{\circ}$C are about two percentage with increasing the pressure, therefore the polarographic reduction under the high pressure is controlled by diffusion. The linear relationships between diffusion current and concentration of metal complex ions are established over all pressure range.

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Pharmacological Action of Panax Ginseng on the Behavioral Toxicities Induced by Psychotropic Agents

  • Kim Hyoung-Chun;Shin Eun-Joo;Jang Choon-Gon;Lee Myung-Koo;Eun Jae-Soon;Hong Jin-Tae;Oh Ki-Wan
    • Archives of Pharmacal Research
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    • v.28 no.9
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    • pp.995-1001
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    • 2005
  • Morphine-induced analgesia has been shown to be antagonized by ginseng total saponins (GTS), which also inhibit the development of analgesic tolerance to and physical dependence on morphine. GTS is involved in both of these processes by inhibiting morphine-6-dehydrogenase, which catalyzes the synthesis of morphinone from morphine, and by increasing the level of hepatic glutathione, which participates in the toxicity response. Thus, the dual actions of ginseng are associated with the detoxification of morphine. In addition, the inhibitory or facilitated effects of GTS on electrically evoked contractions in guinea pig ileum (I-L-receptors) and mouse vas deferens $(\delta-receptors)$ are not mediated through opioid receptors, suggesting the involvement of non-opioid mechanisms. GTS also attenuates hyperactivity, reverse tolerance (behavioral sensitization), and conditioned place preference induced by psychotropic agents, such as methamphetamine, cocaine, and morphine. These effects of GTS may be attributed to complex pharmacological actions between dopamine receptors and a serotonergic/adenosine $A_{2A}1\delta-opioid$ receptor complex. Ginsenosides also attenuate the morphine-induced cAMP signaling pathway. Together, the results suggest that GTS may be useful in the prevention and therapy of the behavioral side effects induced by psychotropic agents.

A Study on the Attenuation of High-frequency P and S Waves in the Crust of the Southeastern Korea using the Seismic Data in Deok-jung Ri (덕정리 지진자료를 이용한 한국남동부지역 지각의 P, S파 감쇠구조 연구)

  • Chung, Tae-Woong;Sato, Haruo
    • Journal of the Korean Geophysical Society
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    • v.3 no.3
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    • pp.193-200
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    • 2000
  • The attenuation characteristics($Q^{-1}$) are important factors representing the physical properties of the Earth interiors, and are essential for the quantitative prediction of strong ground-motion. Based on 156 earthquakes including 76 single-station record on the seismic station located Deok-jung Ri, southeastern Korea, we made the simultaneous measurement of P and S wave attenuation($Q_P^{-1}\;and\;Q_S^{-1}$) by means of extended coda-normalization method. Estimated $Q_P^{-1}\;and\;Q_S^{-1}$ decreased from $1{\times}10^{-2}\;and\;9{\times}10^{-3}$ at 1.5 Hz to $6{\times}10^{-4}\;and\;5{\times}10^{-4}$ at 24 Hz, respectively. This can be expressed by $Q_P^{-1}=0.01\;f^{-1.07}\;and\;Q_S^{-1}=0.01\;f^{-1.03}$ which indicate strong frequency dependence.

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Simulation of Manipulating Various Pulsed Laser Operations Through Tuning the Modulation Depth of a Saturable Absorber (포화 흡수체의 투과변조깊이 조절을 통한 다양한 펄스상태 조작 방법에 관한 전산 모사)

  • Gene, Jinhwa;Yeom, Dong-Il;Kim, Byoung Yoon
    • Korean Journal of Optics and Photonics
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    • v.28 no.6
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    • pp.351-355
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    • 2017
  • In this paper, we conduct a simulation of manipulating various pulsed laser operations through tuning the modulation depth of the saturable absorber in a laser cavity. The research, showing that various pulsed operations could be manipulated from Q-switching through Q-switched mode locking to mode locking by tuning the modulation depth of the saturable absorber in a cavity, has been studied by experimental means. We conduct a simulation with the Haus master equation to verify that these experimental results are consistent with expectations from theory. The time dependence of the gain was considered to express Q-switching fluctuation through applying a rate equation with the Haus master equation. Laser operation was manipulated from mode locking through Q-switched mode locking to Q-switching as modulation depth was increased, and this result agreed well with the theoretical expectation.

Clinical and Neuropsychological Characteristics of Adult Alcohol Use Disorder Patients with or without Attention-Deficit Hyperactivity Symptom (성인 알코올사용장애 환자에서 주의력결핍 과잉행동 증상 유무에 따른 임상적 및 신경심리학적 특성)

  • Jo, Jung Min;Lee, Dong Jun;Jung, Kyung Hi;Oh, Song In;Ahn, Dong Hyun
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.25 no.4
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    • pp.209-216
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    • 2014
  • Objectives : Alcohol use disorder (AUD) is often comorbid with adult attention-deficit hyperactivity disorder (ADHD) and other psychiatric illnesses. When associated with other mental problems, the prognosis of the AUD can be more serious. This study shows research on the clinical and neuropsychological characteristics according to whether or not ADHD symptoms and AUD were comorbid. Methods : A total of 64 adult inpatients who completed AUD scales about adult ADHD, alcohol dependence, depression, anxiety, and impulsiveness. They also completed neuropsychological tests about attention and executive function. According to the Adult ADHD Self-Report Scale score, patients were categorized into two groups (ADHD symptom positive/negative group). Results : Fourteen among the 64 subjects were part of the ADHD symptom positive group (21.9%). They had statistically significant shorter abstinence periods and a higher rate of history of 'rule violation during school' and 'physical damage in childhood' compared to the ADHD symptom negative group. Conclusion : The comorbidity rate with ADHD symptom in adult AUD is higher than the general population. The ADHD symptom positive group suffered from more severe and refractory AUD. Considering the more frequent history of rule violation during school in the ADHD symptom positive group, the association between ADHD and AUD may be mediated by conduct disorder. Therefore we suggest the necessity of careful evaluation and intervention in children and adolescents with ADHD and conduct disorder.

A Study on the Variables that Influence Stages of Change in Smoking Cessation (금연실천단계의 영향변인에 대한 연구)

  • Chang Sung-Ok;Park Chang-Seung
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.8 no.3
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    • pp.391-401
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    • 2001
  • Purpose: The purpose of this study was to identify variables that influence smoking cessation based on the transtheoretical model. Methods: Variables that influence the stages of change in smoking cessation were selected based on transtheoretical model. Data were collected from 176 men aged 30-64 who smoked, Data collection was done in community settings in Seoul and vicinity, Korea between December, 1999 and June, 2000. Data were analyzed by descriptive statistics and logistic analysis using the pc-SAS program. Results: According to the logit model, the influence of significant variables on stage of change for smoking cessation suggest that ; When the scores for Pros in decision making for smoking cessation are high, the possibility that the subjects are in the action, precontemplation and contemplation stage of change will be lower than the possibility that the subjects are in the maintenance stage of change. When the scores of habitual craving in smoking temptation is high, the possibility that the subjects are in the precontemplation and contemplation stage of change will be higher than the possibility that the subjects are in the maintenance stage of change. When the scores of smoking temptation in negative affect situations are high, the possibility that the subjects are in the contemplation stage of change will be higher than the possibility that the subjects are in the maintenance stage of change. When the scores of cognitive process in the process of change are high, the possibility that the subjects are in the contemplation stage of change will be higher than the possibility that the subjects are in the maintenance stage of change. Conclusions : The results provide evidence that physical and psychological dependence on smoking are main barriers to smoking cessation. Therefore nursing interventions based on stage that focus on increasing motivation and intention for smoking cessation need to be developed.

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A Study on the Physical Properties of xB2O3-yBi2O3-zPbO-5SiO2 Glass System (xB2O3 -yBi2O3-zPbO-5SiO2계 유리의 전기적인 특성)

  • Joung, Maeng Sig;Ju, Kyung Bok;Lee, Nam Han
    • Journal of Korean Ophthalmic Optics Society
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    • v.6 no.1
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    • pp.111-117
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    • 2001
  • The temperature dependence of dielectric constant and electrical conductivity for the BBPS glasses system was studied over a temperature range between $30^{\circ}C$ and $500^{\circ}C$ and at a frequency ranged from $10^3$ Hz to $10^7$ Hz. The dielectric constant ${\varepsilon}$ at room temperature of $xB_2O_3-yBi_2O_3-zPbO-5SiO_2 $ glasses was measured to be 15 at $10^5$ Hz for all samples and found to be almost frequency independent. At the relatively low temperature ranger (<$70^{\circ}C$), the dielectric constant was almost temperature independent and above that it increased with increasing temperature: the rate of increase being different at different frequencies. This behavior could be explained on the basis of the presence of molecular dipoles. The dielectric constant was found to depend on the composition as well as the crystalline phases formed in the glass matrix.

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Therapeutic Effects of Panax ginseng on the Neurotoxicity Induced by Abuse Drugs

  • Oh Ki-Wan
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2005.11a
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    • pp.49-66
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    • 2005
  • Panax ginseng has been useful for the treatment of diverse disease in oriental countries for thousands of years. In addition, a folk medicine prescribed by seven herbal drugs including Panax ginseng has been antinarcotics in the treatment of morphine-dependent patients. Many articles have been reported on these works. Therefore, we review the protective effects of Panax ginseng on the neurotoxicity induced by abuse drugs. Ginseng total saponins (GTS) extracted and isolated by Panax ginseng antagonized Morphine-induced analgesia, and inhibited the development of analgesic tolerance to and physical dependence on morphine. GTS inhibited morphine-6 dehydrogenase, which catalyzes production of mophinone from morphine, and increased hepatic glutathione level responsible to toxicity. Therefore, we hypothesized that these dual actions of ginseng can be associated with the detoxication of morphine. In addition, the inhibitory or facilitated effects of GTS on electrically evoked contraction in guinea pig ileum ($\mu$-receptors) and mouse vas deferens($\delta$-receptors) were not mediated through opioid receptors, suggesting non-opioid mechanisms. On the hand, antagonism of U-50,488H ($\kappa$-agonist)-induced antinociception is mediated by serotonergic mechanisms. GTS also inhibited hyperactivity, reverse tolerance (sensitization) and conditioned place preference-induced by psychostimulants such as methamphetamine, cocaine and morphine. On the other hand, GTS reduced the dopamine levels induced by methamphetamine. Moreover, GTS blocked the development of dopamine receptor activation, showing antidopaminergic effect. We suggest that GTS Prevent the methamphetamine-induced striatal dopaminergic neurotoxicity. In addition, Ginsenoside also attenuates morphine-induced cAMP signaling pathway. These results suggested that GTS might be useful for the therapy of the adverse actions of drugs with abuse liability.

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INITIATION OF LIPID PEROXIDATION AS A RESULT OF THE COMBINED ACTION OF FERRIC IRON AND LIGHT ON MEMBRANES

  • Park, Zee-Yong;Kim, Chang-Sook;Jung, Jin
    • Journal of Photoscience
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    • v.1 no.2
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    • pp.83-88
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    • 1994
  • The synergic effect of iron plus blue light on the peroxidation of membrane lipid was investigated, using liposomes made of phospholipid. While strong irradiation did not affect Fe$^{+2}$-promoted lipid peroxidation that turned out to be O$_2$-dependent, ferric iron in bright light exerted a pronounced effect on the initiation of lipid peroxidation: this combined action of light and Fe$^{+3}$ on liposomal membranes was apparently independent of O$_2$. When liposomal samples containing Fe$^{+3}$ were subjected to irradiation, some portions of Fe$^{+3}$ were converted into Fe$^{+2}$. The extent of the Fe$^{+3}$-Fe$^{+2}$ conversion increased with increasing time of irradiation, which resembled the dependence of Fe$^{+3}$-promoted lipid peroxidation on irradiation. Further, it was observed that the effect of irradiation in liposomal samples containing Fe$^{+2}$ was strikingly mimicked by that of Fe$^{+2}$ addition to the same samples. The obligatory requirement of a suitable Fe$^{+3}$/Fe$^{+2}$ ratio for the genesis of iron-dependent lipid peroxidation, a controversial proposition, was also confirmed by the observation that lipid peroxidation was substantially enhanced by the addition of a mixture of Fe$^{+3}$ and Fe$^{+2}$, as compared to the addition of Fe$^{+3}$ or Fe$^{+2}$ alone. The results obtained in this study not only suggest that light acts as an effector for initiating lipid peroxidation, when Fe$^{+3}$ is present in membrane systems, but also imply that any chemical or physical factor that influences the redox states of iron in membranes can play a role in lipid peroxidation reactions.

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