• Title/Summary/Keyword: Releasing test

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The Reduced Model Test for the Determination of Ventilation Velocity to Prevent Backflow in Uni-directional Road Tunnel during a Fire Disaster (일방향 도로터널내 화재 발생시 역류를 막는 환기속도결정에 관한 축소모형실험)

  • 유영일;이희근
    • Tunnel and Underground Space
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    • v.8 no.2
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    • pp.107-117
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    • 1998
  • In the case of a fire disaster in a uni-directional road tunnel, it is important to determine the critical ventilation velocity to prevent the backflow travelling toward the tunnel exit where vehicles are stopped. The critical ventilation velocity is horizontal velocity to prevent hot smoke from moving toward the tunnel exit. According to Froude modelling, the model tunnel whcih was 300mm in diameter and 21 m in length was made of acryl tubes. Inner section of acryl tubes was clothed with polycarbonate. 1/20 scaled model vehicles were installed to simulate the situation that vehicles are stopped in the tunnel exit. Methanol in a pool type burner was burned in the middle of tunnel to simulate a fire hazard. In this study, the basis of determining the critical ventilation velocity is the ventilation flow rate that is able to maintain the allowable CO concentration in the tunnel section. We assumed that the allowable CO concentration was backflow dispersion index. Futhermore, We intended to find out CO distribution and temperature distribution according as we changed ventilation velocity. The results of this study were that no backflow happened when ventilation velocity was 0.52 m/s in the case of 5.75 kW. If we adapt these results of a fire disaster releasing 10MW heat capacity in real tunnel which is 400m in length, no backflow happens when ventilation velocity is 2.31m/s. After we figured out dimensionless heat release rate and dimensionless ventilation velocity of model test and those of real test to verify experimental correctness, we tried to find out correlation between experimental results of model tunnel and those of real tunnel.

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L-Tetrahydropalmatine Ameliorates Development of Anxiety and Depression-Related Symptoms Induced by Single Prolonged Stress in Rats

  • Lee, Bombi;Sur, Bongjun;Yeom, Mijung;Shim, Insop;Lee, Hyejung;Hahm, Dae-Hyun
    • Biomolecules & Therapeutics
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    • v.22 no.3
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    • pp.213-222
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    • 2014
  • Abnormal adaptation of the stress-response system following traumatic stress can lead to alterations in the hypothalamic-pituitaryadrenal (HPA) axis that may contribute to the development of post-traumatic stress disorder (PTSD). The present study used several behavioral tests to investigate the anxiolytic-like and antidepressant activity of L-tetrahydropalmatine (L-THP) in an experimental rat model of anxiety and depression induced by single prolonged stress (SPS), an animal model of PTSD. Male rats were treated intraperitoneally (i.p.) with vehicle or varied doses of THP 30 min prior to SPS for 8 consecutive days. Daily THP (50 mg/kg) administration significantly increased the number and duration of open arm visits in the elevated plus maze (EPM) test, reduced the anxiety index, increased the risk assessment, and increased the number of head dips over the borders of the open arms after SPS. THP was also associated with increased time spent at the center of the open field, reduced grooming behaviors in the EPM test, and reduced time spent immobile in the forced swimming test (FST). It also blocked the decrease in neuropeptide Y (NPY) and the increase in corticotrophin-releasing factor (CRF) expression in the hypothalamus. This is the first study to determine that THP exerts pronounced anxiolytic-like and antidepressant effects on the development of the behavioral and biochemical symptoms associated with PTSD, indicating its prophylactic potential. Thus, THP reversed several behavioral impairments triggered by the traumatic stress of SPS and is a potential non-invasive therapeutic intervention for PTSD.

Bupleurum falcatum Prevents Depression and Anxiety-Like Behaviors in Rats Exposed to Repeated Restraint Stress

  • Lee, Bom-Bi;Yun, Hye-Yeon;Shim, In-Sop;Lee, Hye-Jung;Hahm, Dae-Hyun
    • Journal of Microbiology and Biotechnology
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    • v.22 no.3
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    • pp.422-430
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    • 2012
  • Previous studies have demonstrated that repeated restraint stress in rodents produces increases in depression and anxiety-like behaviors and alters the expression of corticotrophin-releasing factor (CRF) in the hypothalamus. The current study focused on the impact of Bupleurum falcatum (BF) extract administration on repeated restraint stress-induced behavioral responses using the forced swimming test (FST) and elevated plus maze (EPM) test. Immunohistochemical examinations of tyrosine hydroxylase (TH) expression in rat brain were also conducted. Male rats received daily doses of 20, 50, or 100 mg/kg (i.p.) BF extract for 15 days, 30 min prior to restraint stress (4 h/day). Hypothalamic-pituitary-adrenal axis activation in response to repeated restraint stress was confirmed base on serum corticosterone levels and CRF expression in the hypothalamus. Animals that were pre-treated with BF extract displayed significantly reduced immobility in the FST and increased open-arm exploration in the EPM test in comparison with controls. BF also blocked the increase in TH expression in the locus coeruleus of treated rats that experienced restraint stress. Together, these results demonstrate that BF extract administration prior to restraint stress significantly reduces depression and anxiety-like behaviors, possibly through central adrenergic mechanisms, and they suggest a role for BF extract in the treatment of depression and anxiety disorders.

Effects of Mixture of Citri Peticulatae Viride Pericarpium and Lycii Radicis Cortex on the Change of HPA-Axis and Catecholamic System in the Forced Swimming Test (청피(靑皮)와 지골피(地骨皮) 복합제(複合劑)가 강제수영부하실험에서 CRF, c-Fos와 TH의 변화에 미치는 영향)

  • Park, Soo-Hyun;Lee, Tae-Hee
    • The Korea Journal of Herbology
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    • v.25 no.2
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    • pp.117-128
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    • 2010
  • Objectives : In this study the antidepressant effects of mixture of Citri Peticulatae Viride Pericarpium and Lycii Radicis Cortex on the change of HPA-Axis and Catecholamic system was investigated Methods : The forced swimming test(FST) was performed. The expression of corticotropin-releasing factor(CRF), c-Fos in the paraventricular nucleus(PVN), and tyrosine hydroxylase(TH) in the ventral tegmental area(VTA) and locus coeruleus(LC) was measured with immunohistochemical method and the concentration of seum adrenocorticotropic hormone(ACTH) was measured with ELISA method. And the experimental groups were divided into the extraction after mixing(A) and mixture after extraction(B). The effects of both group were compared. Results : The duration of immobility in the forced swimming test was significantly decreased in the A400 group(P<0.01). The expression of CRF in PVN were significantly reduced in the A100, A400, B100, B400groups(P<0.001). but the expression of c-fos in PVN weren't reduced in all groups. And the concentration of ACTH in Plasma were significantly reduced in the A 100 group(P<0.01). The expression of TH in LC were significantly reduced in the A 400, B 100 and B400 groups(P<0.05~P<0.01). Conclusion : Mixture of Citri Peticulatae Viride Pericarpium and Lycii Radicis Cortex has antidepressant effects. But the difference between mixing and extracting methods was not shown.

Increased accuracy of estrus prediction using ruminoreticular biocapsule sensors in Hanwoo (Bos taurus coreanae) cows

  • Daehyun Kim;Woo-Sung Kwon;Jaejung Ha;Joonho Moon;Junkoo Yi
    • Journal of Animal Science and Technology
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    • v.65 no.4
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    • pp.759-766
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    • 2023
  • Visual estrus observation can only be confirmed at a rate of 50%-60%, which is lower than that obtained using a biosensor. Thus, the use of biosensors provides more opportunities for artificial insemination because it is easier to confirm estrus than by visual observation. This study determines the accuracy of estrus prediction using a ruminoreticular biosensor by analyzing ruminoreticular temperature during the estrus cycle and measuring changes in body activity. One hundred and twenty-five Hanwoo cows (64 with a ruminal biosensor in the test group and 61 without biosensors in the control group) were studied. Ruminoreticular temperatures and body activities were measured every 10 min. The first service of artificial insemination used gonadotropin-releasing hormone (GnRH)-based fixed-time artificial insemination protocol in the control and test groups. The test group received artificial insemination based on the estrus prediction made by the biosensor, and the control group received artificial insemination according to visual estrus observation. Before artificial insemination, the ruminoreticular temperature was maintained at an average of 38.95 ± 0.05℃ for 13 h (-21 to -9 h), 0.73℃ higher than the average temperature observed at -48 h (38.22 ± 0.06℃). The body activity, measured using an indwelling 3-axis accelerometer, averaged 1502.57 ± 27.35 for approximately 21 h from -4 to -24 h before artificial insemination, showing 203 indexes higher body activity than -48 hours (1299 ± 9.72). Therefore, using an information and communication techonology (ICT)-based biosensor is highly effective because it can reduce the reproductive cost of a farm by accurately detecting estrus and increasing the rate of estrus confirmation in cattle.

A comparative study of the puberty suppression effect of gonadotropin-releasing hormone agonist in precocious or early puberty girls (중추성 성조숙증 및 조기 사춘기 여아에서 성선자극호르몬 방출호르몬작용제의 용량에 따른 사춘기 억제 효과 비교)

  • Shim, Kye-Shik;Bae, Chong-Woo;Yang, You-Jung
    • Clinical and Experimental Pediatrics
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    • v.51 no.6
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    • pp.634-639
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    • 2008
  • Purpose : There has been considerable disagreement regarding the most appropriate dosage of gonadotropin-releasing hormone agonist in cases of central precocious puberty. The aim of this study was to determine the appropriate dosage for suppression of the puberty in girls with central precocious or early puberty. Methods : Twenty-two girls with early puberty were randomly subjected to 3 types of dosages of leuprolide acetate for at least 6 months. The number of cases in groups 1, 2, and 3 were 7, 7, and 8, and dosages were 70, 90, and $110{\mu}g/kg/-month$, respectively. Height, weight, bone age, Tanner stage of breast development, and serum levels of LH, FSH, estradiol, and progesterone were measured before treatment and after 6 months of treatment. The number of cases of puberty suppression was compared using a modified puberty suppression score with a nonparametric chi-square test. Results : There were no significant differences of chronologic and bone ages among the groups. There was a significant decrease in height SDS gain after 6 months in group 3 (P<0.05) compared with groups 1 and 2. Serum levels of LH, FSH, estradiol and progesterone were all significantly decreased after treatment in all 3 groups (P<0.05). The number of cases of puberty suppression in each group were 4 (57%), 5 (71%), and 8 (100%). There was a significantly increased proportion of suppression of puberty in group 3 (P<0.05). Conclusion : It was necessary to use a higher dose of gonadotropin-releasing hormone agonist to suppress early puberty in girls; however further longitudinal study will be needed for their prognosis of final adult height.

A Research about Implementation of Fuzzy Control Algorithm with Variable Input Gain for Improving Performance of Tension Control (장력제어 성능개선을 위한 가변 입력이득 퍼지제어알고리즘 적용에 관한 연구)

  • Sul, Jae-Hoon;Park, Jong-Oh;Jang, Jong-Seung;Lim, Young-Do
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.8
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    • pp.680-688
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    • 2001
  • In this paper, the fuzzy control with variable input gain is applied to maintain the consistent tension in the process of taking up and releasing texture. In the process of discharging web on one side rolling it on another, the take-up drum gets smaller on the release drum side as it gets bigger on the rolling side, thus it is necessary to change the balance of velocity between the sides. In order to solve the problem a tension controller is necessary. The PI control method has been employed to maintain the consistent tension, but the PI control method produces a problem which requires an experienced worker with the traits of the machine, in order to perform the fine adjustments according to the environment of the process. For solving the above problem, we apply fuzzy control to the tension system, in order to produce a uniform roll. For the performance test, the fuzzy controller does not need to revise the parameters. Therefore the fuzzy controller exhibits an excellent additivity for the tension system where the system is changed with time.

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Succinylated Pullulan Acetate Microspheres for Protein Delivery

  • Woo, Young-Rong;Seo, Seog-Jin;Na, Kun
    • Journal of Pharmaceutical Investigation
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    • v.41 no.6
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    • pp.323-329
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    • 2011
  • In order to develop new protein carrier replacing poly(DL-lactic acid-co-glycolic acid) (PLGA) microspheres, succinylated pullulan acetate (SPA) was investigated to fabricate a long term protein delivery carrier. SPA microspheres loaded with lysozyme (Lys) as a model protein drug were prepared by a water/oil/water (W/O/W) double emulsion method. An acidity test of SPA copolymers after hydrolysis was performed to estimate the change of protein stability during releasing proteins from the microspheres. There was no pH change of SPA copolymers, but pH of PLGA polymers after hydrolysis was significantly decreased to around pH 2, indicating that the long-term stability of proteins released from SPA microspheres can be guaranteed. Loading efficiency of proteins into SPA microspheres was three times higher than those into conventional PLGA microspheres, indication of inducing stronger charge interaction between proteins and succinyl groups in SPA microspheres. Although initial burst behaviors were monitored in Lys-loaded SPA microspheres due to relatively strong hydrophilic succinyl segments in SPA microspheres, initial burst issues would be circumvented if the ratio of charge density of succinyl moieties and hydrophobic acetate groups is harmonically controlled. Therefore, in this study, a new attempt of protein delivery system was made and functional SPA was successfully confirmed as a new protein carrier.

Camber calculation of prestressed concrete I-Girder considering geometric nonlinearity

  • Atmaca, Barbaros;Ates, Sevket
    • Computers and Concrete
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    • v.19 no.1
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    • pp.1-6
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    • 2017
  • Prestressed concrete I-girders are subject to different load types at their construction stages. At the time of strand release, i.e., detensioning, prestressed concrete girders are under the effect of dead and prestressing loads. At this stage, the camber, total net upward deflection, of prestressed girder is summation of the upward deflection due to the prestressing force and the downward deflection due to dead loads. For the calculation of the upward deflection, it is generally considered that prestressed concrete I-girder behaves linear-elastic. However, the field measurements on total net upward deflection of prestressed I-girder after detensioning show contradictory results. In this paper, camber calculations with the linear-elastic beam and elastic-stability theories are presented. One of a typical precast I-girder with 120 cm height and 31.5 m effective span length is selected as a case study. 3D finite element model (FEM) of the girder is developed by SAP2000 software, and the deflections of girder are obtained from linear and nonlinear-static analyses. Only geometric nonlinearity is taken into account. The material test and field measurement of this study are performed at prestressing girder plant. The results of the linear-elastic beam and elastic-stability theories are compared with FEM results and field measurements. It is seen that the camber predicted by elastic-stability theory gives acceptable results than the linear-elastic beam theory while strand releasing.

Recurrent hemoptysis in a 26-year-old woman with a ground-glass opacity lesion of the lung

  • Kim, Jong Ha;Park, Sin-Youl
    • Journal of Yeungnam Medical Science
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    • v.37 no.1
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    • pp.59-62
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    • 2020
  • Hemoptysis is a major reason for emergency department (ED) visits. Catamenial hemoptysis (CH), a rare condition of thoracic endometriosis, can cause recurrent hemoptysis but is difficult to diagnose in the ED due to the scarcity of cases and nonspecific clinical findings. We report a case of a 26-year-old woman who presented to the ED with recurrent hemoptysis since 2 years without a definite cause. Her vital signs and blood test findings were unremarkable. Chest computed tomography (CT) did not show any specific lesions other than a non-specific ground-glass opacity pattern in her right lung. She was on day 4 of her menstrual cycle and her hemoptysis frequently occurred during menstruation. Although there was no histological confirmation, based on her history of hemoptysis during menstruation and no other cause of the hemoptysis, the patient was tentatively diagnosed with CH and was administered gonadotropin-releasing hormone. She had no recurrence of hemoptysis for 3 months. While CH is difficult to diagnose in the ED, the patient's recurrent hemoptysis related to menstruation was a clue to the presence of CH. Therefore, physicians should determine the relationship between hemoptysis and menstruation for women of childbearing age presenting with repeated hemoptysis without a definite cause.