• Title/Summary/Keyword: $LR_{2}$

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Further Applications of Johnson's SU-normal Distribution to Various Regression Models

  • Choi, Pilsun;Min, In-Sik
    • Communications for Statistical Applications and Methods
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    • v.15 no.2
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    • pp.161-171
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    • 2008
  • This study discusses Johnson's $S_U$-normal distribution capturing a wide range of non-normality in various regression models. We provide the likelihood inference using Johnson's $S_U$-normal distribution, and propose a likelihood ratio (LR) test for normality. We also apply the $S_U$-normal distribution to the binary and censored regression models. Monte Carlo simulations are used to show that the LR test using the $S_U$-normal distribution can be served as a model specification test for normal error distribution, and that the $S_U$-normal maximum likelihood (ML) estimators tend to yield more reliable marginal effect estimates in the binary and censored model when the error distributions are non-normal.

Experimental research on the creep buckling of fire-resistant steel columns at elevated temperature

  • Yang, Kuo-Chen;Yu, Zong-Han
    • Steel and Composite Structures
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    • v.15 no.2
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    • pp.163-173
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    • 2013
  • The thermal creep is one of the major factors causing the buckle of steel columns in the fire events. But, few related studies have been reported to evaluate the factors affecting the thermal creep of steel column experimentally or numerically. In this study a series of Fire-resistant steel columns with three different slenderness ratios under a sustained load are tested under a uniform temperature up to six hours in order to evaluate the creep upon three selected factors, temperature, applied load, and column slenderness. Based on experimental results, a proposed creep strain rate model is established as the function of a single parameter of the load ratio of temperature LR(T) to determine the buckling time of steel column due to creep. Furthermore it is found that the creep can be neglected when LR(T) is smaller than 0.77.

A Study on Volume of Difference of Two Joint pdf′s, Focused on the Relation to Normal Theory LR Tests

  • Lee, Kwangjin
    • Communications for Statistical Applications and Methods
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    • v.10 no.3
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    • pp.749-764
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    • 2003
  • In this paper we explain that normal theory likelihood-ratio tests(z, t, $x^2$. F) for mean(s) or variance(s) can be geometrically related to volume of difference of two joint pdf's. One is an estimated joint pdf under null parameter space $\omega$ and the other is an estimated joint pdf under full parameter space $\Omega$. For explanations, ‘distance between two distributions’ is defined. We study properties of it, and derive some results on the distance between two multivariate normal distributions.

Occurrence of Microcystin-Containing Toxic Water Blooms in Central India

  • Agrawal Manish K.;Ghosh Shubhro K.;Bagchi Divya;Weckesser Juergen;Erhard Marcel;Bagchi Suvendra N.
    • Journal of Microbiology and Biotechnology
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    • v.16 no.2
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    • pp.212-218
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    • 2006
  • Three out of fourteen Microcystis-dominant cyanobacterial blooms in Central India were found to be toxic to mice ($LD_{50}$ ranging from 35-450 mg bloom dry mass/kg body weight). The liver architecture of the treated mice showed characteristic symptoms of hepatotoxicity relative to the untreated controls, with increased enzyme activities of serum lactate dehydrogenase (LDH), serum glutamate oxaloacetate transaminase (SGOT), alkaline phosphatase (ALP), and serum glutamate pyruvate transaminase (SGPT). RP-HPLC revealed the presence of microcystin-LR, microcystin-RR, and desmethyl microcystin-RR in the given region to maximum amounts of 390, 1,030, and $860{\mu}g/g$ bloom dry weight, respectively, corresponding to a maximum of 2.8 mg/l microcystin-LR in the lake water. Further confirmation of the microcystin variants was conducted using a MALDI-TOF MS analysis.

Alterations of Cerebral Metabolic Activation Following Electro-Acupuncture Stimulation on ST36 and LR3 Acu-Points in Rats (흰쥐의 족삼리 및 태충 전침자극에 따른 뇌대사활성의 변화)

  • Sohn, Young-Joo;Jung, Hyuk-Sang;Ku, Ja-Seung;Won, Ran;Kim, Yong-Suk;Park, Young-Bae;Sohn, Nak-Won
    • Journal of Acupuncture Research
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    • v.19 no.1
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    • pp.159-174
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    • 2002
  • Objective : The meridian theory in oriental medicine explains that each acu-point has a characteristic functional effect. It will be supposed that an acupuncture stimulation on different acu-point evokes different activation on different areas in the central nervous system(CNS) according to the meridian theory. On this supposition, our group tried the semi-quantitative [14C]2-deoxyglucose([14C]2-DG) autoradiography on the acupuncture stimulation to the hindlimb acu-points of Sprague-Dawley rats. Methods : A venous catheter for the intravenous administration of isotope was equipped in the right external jugular vein on 3 days prior to the [14C]2-DG study. On the day of the study, two acupuncture needles were inserted into the ST36(Zusanli) or LR3(Taichong) on the left hindlimb. Electro-acupuncture stimulation (2 Hz, 5 ms, 1~3 mA, 15 minutes) started just before the i.v. injection of [14C]2-DG ($25{\mu}Ci/rat$). The brain and the spinal cord were removed and processed for the [14C] 2-DG autoradiography. Results : The EA stimulation on ST36 reveals over 120% metaboilc activation in Arcuate nucleus, Anterior pretectal nucleus, Dorsal cochlear nucleus, Interposed cerebellar nucleus, and Nucleus of Darkschewitsch. The EA stimulation on LR3 reveals over 120% metaboilc activation in Lateral habenula nucleus, Medial vestibular nucleus, Ventromedial thalamic nucleus, Anteroventral thalamic nucleus, Anterior cingulate cortex, Dentate gyrus, Antero cortical amygdaloid nucleus, Anterior pretectal nucleus, and Dorsal tegmental nucleus compared with the non EA stimulation control group. Conclusion : These results demonstrate that the different acu-points evoke the different activations in brain areas. And with this functional brain mapping study, a new scientific elucidation for the basis of the acupuncture-meridian theory in oriental medicine through differences of activated area in CNS according to the each acupuncture point.

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Differential effect of electroacupuncture analgesia depending on the point selection in a rat model of CFA-induced arthritis (CFA로 유도한 관절염에서 선혈(選穴)에 따른 전침(電鍼)의 진통효과 차이)

  • Yang, Bum-Sik;Koo, Sung-Tae;Kim, Kyoung-Sik;Sohn, In-Cheul
    • Korean Journal of Acupuncture
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    • v.22 no.1
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    • pp.95-108
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    • 2005
  • Objective : In the present study, the effect of electroacupuncture (EA) applied to several acupoints and non-acupoint in CFA-induced knee arthritis was examined. Methods : A common source of persistent pain in humans is arthritis. Arthritis was induced by injection of CFA $125\;{\mu}l$ into knee joint cavity under enflurane anesthesia. The rat subsequently showed swelling of the ankle and a reduced stepping force of the affected limb for the next several days. The reduced stepping force of the limb was presumably due to a painful knee. EA was applied to either of $LR_2,\;LI_4$, or non-acupoint on the contralateral forelimb for 30 min under gaseous anesthesia. After the termination of EA, behavioral tests measuring stepping force were periodically conducted during the next 4 h. Results : EA applied to $LR_2$ point produced a significant improvement of stepping force of the affected foot lasting for at least 2 h. However, neigher $LI_4$ point nor non-point produced any significant increase of weight bearing force. The improvement of stepping pressure was interpreted as an analgesic effect. The analgesic effect was specific to the acupuncture point since the analgesic effect on CFA-induced knee arthritic pain model could not be mimicked by EA applied to a point, $LI_4$ or non-acupoint. In addition, both NO production and iNOS protein expression increased by arthritis were suppressed by EA applied to $LR_2$ point. Conclusion : These data suggest that EA produces a potent analgesic effect in the rat model of CFA-induced knee arthritis. This analgesic effect is produced by applying EA to an acupoint at opposite side from the painful area in a stimulus point-specific way.

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Antidepressant Effect of Liver Tonification and Four Gate Acupuncture Treatments and Its Brain Neural Activity (간정격과 사관혈 침 치료의 우울 행동 개선 효과 및 뇌신경 반응성 분석 연구)

  • Eom, Geun-Hyang;Ryu, Jae-Sang;Park, Ji-Yeun
    • Korean Journal of Acupuncture
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    • v.38 no.3
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    • pp.162-174
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    • 2021
  • Objectives : We aimed to identify the antidepressant effect of liver tonification acupuncture treatment (ACU (LT); KI10, LR8, LU8, LR4) and four gate acupuncture treatment (ACU (FG); LI4, LR3) and its brain neural activity in the normal and chronic restraint stress (CRS)-induced mouse model. Methods : Firstly, normal mice were given ACU (LT) or ACU (FG) and the c-Fos expressions in each brain region were analyzed to examine brain neural activity. Secondly, CRS was administered to mice for 4 weeks, then ACU (LT) or ACU (FG) was performed for 2 weeks. The depression-like behavior was evaluated using open field test (OFT) before and after acupuncture treatment. Then, the c-Fos expressions in each brain region were analyzed to examine brain neural activity. Results : In normal mice, ACU (FG) regulated brain neural activities in the hypothalamus, hippocampus, and periaqueductal gray. ACU (LT) changed more brain regions in the prefrontal cortex, insular cortex, striatum, and hippocampus, including those altered by ACU (FG). In CRS-induced model, ACU (LT) alleviated depression-like behavior more than ACU (FG). Also, brain neural activities in the motor cortex area 2 (M2), agranular ventral part and piriform of insular cortex (AIV and Pir), and cornu ammonis (CA) 1 and CA3 of hippocampus were changed by ACU (LT), and those of AIV and CA3 were also changed by ACU (FG). As in normal mice, ACU (LT) resulted in changes in more brain regions, including those altered by ACU (FG) in CRS model. M2, Pir, and CA1 were only changed by ACU (LT) in depression model, suggesting that these brain regions reflect the specific effect of ACU (LT). Conclusions : ACU (LT) relieved depression-like behavior more than ACU (FG), and this acupuncture effect was associated with modulation of brain neural activities in the motor cortex, insular cortex, and hippocampus.

EFFECT OF CANAL TAPERING IN TEETH OF VARIOUS APICAL SIZE & CROSS-SECTIONAL CONFIGURATION ON MICROLEAKAGE (다양한 치근단공 크기와 근관단면의 형태를 가지는 치아에서 taper의 정도가 미세누출에 미치는 영향)

  • Kim, Jung-Hee;Lee, Kyung-Ha;Lee, Se-Joon;Yu, Mi-Kyung;Lee, Kwang-Won
    • Restorative Dentistry and Endodontics
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    • v.30 no.2
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    • pp.95-101
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    • 2005
  • The aim of this study was to evaluate the microleakage of teeth according to root canal preparation with & without apical enlargement in various size of apical foramen. 60 extracted one canal roots were cross-cutted at 5 mm from root apex and divided into two groups according to their apical foramen size of large (L) and small (S). Each group was subdivided into two groups accordance with their cross-sectional configuration at 5 mm from apex, round (R) and ovoid (O); SR Group, SO Group LR Group, LO Group. Each group was shaped in .02 taper by Quantec series Nickel-Titanium (NiTi) rotary file, obturated by lateral condensation method. Leakage was measured using a fluid transport model under 40 $cmH_2O$ pressure. After the leakage test, blocks which had showed the leakage retreated with .04 taper and ,06 taper and evaluated the degree of fluid filtration in each group. The data was analysed statistically using chi-square test and fisher's exact test. The results obtained were as follows : 1. Significant difference in leakage was found in groups which had different apical foramen size in .02 taper instrumentation (p < 0.05), but not in .04 taper instrumentation (p > 0.05) 2. The difference in microleakage according to the shape of canal was not evident at 5 mm from apex (p > 0.05). 3. There was correlation between .02 taper instrumentation and .04 taper instrumentation in LR group, LO group (p < 0.05).

Study on Anti-oxidative Activities and Beverage Preferences Relating to Fermented Lotus Root and Platycodon grandiflorum Extracts with Sugar through Lactic Acid Fermentation (젖산발효한 연근, 도라지 당추출 발효액의 항산화 활성과 음료기호성에 관한 연구)

  • Lee, Kyung-Soo;Kim, Ju-Nam;Chung, Hyun-Chae
    • Journal of the East Asian Society of Dietary Life
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    • v.25 no.1
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    • pp.183-192
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    • 2015
  • This study aimed to produce fermented extracts with sugar made from lotus root (LR) and Platycodon grandiflorum (PG), using lactic acid fermentation, and confirmed their physiological and anti-oxidative activities as basic data for manufacturing functional drinks through sensory tests. For the final sugar concentrations, PG showed $48.1^{\circ}brix$ and LR showed $52.0^{\circ}brix$. Sugar concentrations during lactic acid fermentation following dilution of sugar to $12^{\circ}brix$, ranged from $11.5{\sim}12.1^{\circ}brix$ for PG and $11.9{\sim}12.4^{\circ}C$ for LR. During lactic acid fermentation, lactic acid bacteria numbers tended to decrease in both fermented LR and PG extracts with sugar as the fermentation period increased. For DPPH radical scavenging ability, LR was three times higher in control without lactic acid fermentation while PG showed significant increases in L. acidophilus (77%), L. brevis (90%), and L. delbrueckii (177%) during lactic acid fermentation. For total polyphenol content, LR showed a higher concentration than PG, and except for fermented L. delbrueckii extract showing similarity with the control, contents of fermented extracts decreased. In the case of PG, CUPRAC, increased significantly in L. brevis, whereas FRAP, increased significantly in L. delbrueckii with lactic acid fermentation. For reducing power, except for fermentation with L. brevis, all PG showed lower reducing power activities. In the sensory test of fermented LR and PG extracts with sugar, both fermented extracts showed better results with L. brevis or L. delbrueckii than control or those with L. acidophilus in every item. Based on these results, it is highly possible to develop fermented extract drinks with sugar using LR or PG. In particular, lactic acid bacteria such as L. delbrueckii and L. brevis showed generally higher activities with potential as a functional drink.

Acupuncture at Liver Meridian Protects the Dopaminergic Neuronal Damage in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced Parkinson's Disease Mouse Model (간경보사(肝經補瀉)가 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine로 유도된 파킨슨병 동물 모델에 미치는 영향)

  • Kim Seung-Tae;Chae Youn-Byong;Kim Yun-Jung;Kang Min-Jung;Jung Mi-Young;Chung Joo-Ho;Hahm Dae-Hyun;Lee Sang-Jae;Lee Hye-Jung;Park Hi-Joon
    • Korean Journal of Acupuncture
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    • v.23 no.4
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    • pp.169-176
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    • 2006
  • Objectives : This study was designed to compare the effects of tonification and sedation methods of Liver Meridian in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease mice model. Methods : We injected MPTP (30 mg/kg, i.p.) or saline for 5 consecutive days. Acupuncture treatments were given to the mice with MPTP at LR8 and LR4 to tonify Liver Meridian (Liver+) or LR4 and LR2 to sedate it (Liver-) for 12 day. At the 12th day after first injection, mice were perfused, and then tyrosine hydroxylase (TH)-immunohistochemistry was performed in substantia nigra (SN) of their brains. After counting the number of TH-positive neurons, we compared their numbers among experimental groups. Results : The number of TH-positive neurons of Liver+ group was significantly increased compared to that of MPTP group in the SN. That of Liver-group was also increased more than MPTP group, but not significantly. Conclusions : Tonifying Liver Meridian might be effective therapeutic tools for the neuroprotection in subchronic MPTP-induced mice model.

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