• Title/Summary/Keyword: temperature-induced response

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Effect of Fire Induced Spalling on the Response of Reinforced Concrete Beams

  • Kodur, V.K.R.;Dwaikat, M.B.
    • International Journal of Concrete Structures and Materials
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    • v.2 no.2
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    • pp.71-81
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    • 2008
  • A macroscopic finite element model is applied to investigate the effect of fire induced spalling on the response of reinforced concrete (RC) beams. Spalling is accounted for in the model through pore pressure calculations in concrete. The principles of mechanics and thermodynamics are applied to compute the temperature induced pore pressure in the concrete structures as a function of fire exposure time. The computed pore pressure is checked against the temperature dependent tensile strength of concrete to determine the extent of spalling. Using the model, case studies are conducted to investigate the influence of concrete permeability, fire scenario and axial restraint on the fire induced spalling and also on the response of RC beams. Results from the analysis indicate that the fire induced spalling, fire scenario, and axial restraint have significant influence on the fire response of RC beams. It is also shown that concrete permeability has substantial effect on the fire induced spalling and thus on the fire response of concrete beams. The fire resistance of high strength concrete beams can be lower that that of normal strength concrete beams due to fire induced spalling resulting from low permeability in high strength concrete.

An Experimental study on the anti-allergic effects, anti-inflammatory action, anti-pyretic action and analgesic action of Galgeun-tang, Gamigalgeun-tang and Geomahwanggalgeun-tang (葛根湯과 加味葛根湯의 抗알레르기 및 消炎, 解熱, 鎭痛作用에 대한 實驗的 硏究)

  • Yang, Tae-Kyu;Kim, Yoon-Bum;Chae, Byung-Yoon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.15 no.1
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    • pp.76-95
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    • 2002
  • Allergic rhinitis and allergic dermatitis are common allergic diseases. Galgeun-tang has been used for treating various diseases, which include allergic rhinitis and allergic dermatitis. Experimental sutdies have been done to research the anti-allergic effects of Galgeun-tang, Gamigalgeun-tang and Geomahwanggalgeun-tang. We have observed: the vascular permeability response induced by serotonin and histamine, the contact dermatitis response induced by picryl chloride, the delayed type hypersensitivity response to SRC, the mice paw edema induced by carrageenin, and the rectal temperature in febrile rats induced by endotoxin, as well as the writhing syndrome induced by $0.7{\%}$ acetic acid. The results were as follows: 1. In the vascular permeability response to intradermal serotonin and histamine, Galgeun-tang and Gamigalgeun-tang showed a significant inhibitory effect. However Geomahwanggalgeun-tang showed an insignificant inhibitory effect. 2. In the contact dermatitis response induced by picryl chloride, Galgeun-tang and Gamigalgeun-tang showed a signigicant inhibitory effect. However Geomahwanggalgeun-tang showed an insignificant inhibitory effect. 3. In the delayed type hypersensitivity response to SRC, Galgeun-tang, Gamigalgeun-tang and Geomahwanggalgeun-tang showed a significant inhibitory effect. 4. In the mice paw edema induced by carrageenin, Galgeun-tang and Gamigalgeun-tang showed a significant inhibitory effect. However Geomahwanggalgeun-tang showed an insignificant inhibitory effect. 5. In the rectal temperature in febrile rats induced by endotoxin, Galgeun-tang, Gamigalgeun-tang and Geomahwanggalgeun-tang showed a significant inhibitory effect. 6. In the writhing syndrome induced by a $0.7{\%}$ acetic acid solution. Galgeun-tang and Gamigalgeun-tang showed a significant inhibitory effect. However Geomahwanggalgeun-tang showed an insignificant inhibitory effect.

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Effects of induced heat stress on temperature response and biochemistry: alteration of biochemical constituents in Holstein calves by heat stress

  • Lim, Hyun-Joo;Ki, Kwang-Seok
    • Korean Journal of Agricultural Science
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    • v.46 no.3
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    • pp.637-643
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    • 2019
  • The aim of the present study was to evaluate the effect of the induced heat stress on physiological response and serum biochemical parameters involving glucose, cholesterol, blood urea nitrogen (BUN), non-esterified fatty acids (NEFA), and cortisol in Holstein calves. Ten calves were kept in a climate controlled room (air temperature $37^{\circ}C$ and 90% humidity from 09:00 to 19:00) for three days. Those animals were given a one-day adaptation period. During the treatment period, we measured the skin temperature six times. Following the treatment periods, blood samples were collected before the experiment began (09:00) and at the end of the stress period (19:00). To aid analysis of the biochemical parameters, also we monitored the rectal temperature. The results, exhibited that both rectal and skin temperature showed increase in the heat stress-induced animals as compared with unstressed animals. Moreover, we noticed that the levels of BUN and NEFA increased in the blood serum of heat stress induced animals when compared with un-stressed ones. From these results, we concluded that the physiological and biochemical changes in the calves were induced by heat stress. Hence, the present study findings could be employed as base line data for development of stress reduction techniques in the dairy industry.

Thermosensing of Thermotactic Mutants, Dictyostelium discoideum Amoebae in Vegetative Stage

  • Hong, Choo-Bong
    • Journal of Plant Biology
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    • v.26 no.3
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    • pp.131-139
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    • 1983
  • Temperature response of amoebae of thermotactic mutants have been investigated. Amoebae of the mutant strain HO 428 showed positive thermotaxs which is strong at lower temperaturs and drops sharply above the growth temperature of amoebae. The temperature response of HO 428 amoebae was not affected by the length of amoebae on the grdients. HO 596 amoebae seemed to have both positive and negative thermotactic responses shortly after food depletion. Longer exposure of these amoebae on the thermal gradients induced a stronger negative response at lower temperatures and an apparent positive response at higher temperatures. A similar changes could be observed in HO 1445 amoebae. Based on the steady positive thermotactic response by HO 428 amoebae and the mode of change in termperature response at higher temperatures, 24$^{\circ}C$ and $25^{\circ}C$, by HO 596 amoebae, a model for the temperature response of vegetative Dictyostelium discoideum amoebae, strain HL 50, has been proposed. The main features of the model are: a positive response at the thermal gradients with midpoint temperatures lower than the growth temperatures of amoebae and a negative response above it.

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Experimental sutdy on the anti-allergic effects of Onpyetang and Onpyetang-Gechongbaek (溫肺湯과 溫肺湯去총白의 抗알레르기效果 및 鎭痛, 解熱作用에 대한 實驗的 硏究)

  • Park, Jae-Hyun;Chae, Byun-Yoo
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.14 no.2
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    • pp.154-172
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    • 2001
  • Major symptoms of al1ergic rhinitis are nasal obstruction, sneezing and watery rhinorrhea. Onpyetang has been used to treat for nasal obstruction, which is one of the symptoms of allergic rhinitis. This Experimental study was done to research effects of Onpyetang and transformed Onpyetang(Allii Radix is deducted from Onpyetang) on the anti-allergic effects. We have studied the vascular permeability response induced by serotonin and histamine, the contact dermatitis response induced by picryl chloride, the delayed type hypersensitivity response to SRC, the mice paw edema induced by carrageenin, the writhing syndrome induced by $0.7\%$ acetic acid, and the rectal temperature in febrile rats induced by yeast. The results were as follows : 1. In the vascular permeability response to intradermal serotonin and histamine. Onpyetang proved significant inhibitory effect(P<0.05, p<0.001) But transformed Onpyetang proved significant inhibitory effect only to histamine(P<0.05) 2. In the contact dermatitis response induced by picryl chloride, Onpyetang and transformed Onpyetang proved significant inhibitory effect.(P<0.05, P<0.05) 3. In the delayed type hypersensitivity response induced by SRC, Onpyetang and transformed Onpyetang proved significant inhibitory effect on mice paw edema.. (P<0.05, P<0.05) 4. In the delayed type hypersensitivity response induced by SRC, Onpyetang proved significant inhibitory effect to serum IgE.(P<0.01) But transformed Onpyetang proved insignificant inhibitory effect on serum Ig E. 5. In the mice paw edema induced by carrageenin, Onpyetang and transformed Onpyetang proved significant anti-inflammatory effect. (P<0.01, P<0.01) 6. In the writhing syndrome induced $0.7\%$ acetic acid, Onpyetang and transformed Onpyetang proved significant analgestic effect. (P<0.01, P<0.01) 7. In the rectal temperature in febrile rats induced by yeast, Onpyetang and transformed Onpyetang proved significant anti-pyretic effect.(P<0.001, P<0.01) according to this result Onpyetang was conclude to be effective on anti-allergic, anti-pyretic, anti-inflammatory and analgestic action. but transformed Onpyetang(Allii Radix is deducted from Onpyetang) was not effective on the vascular permeability response to intradermal serotonin and increasing Ig E of delayed type hypersensitivity response induced by SRC. In addition, transformed Onpyetang is not effective as Onpyetang. More study should be done about the role of Allii Radix.

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Influence of Each Fraction from Panax Ginseng on the Hypothermia in Mice Elicited by Reserpine, Nembutal and Chlorpromazine (인삼(人蔘) 각(各) Fraction이 Nembutal, Chlorpromazine 및 Reserpine 투여(投與)로 인(因)한 Mouse체온하강(體溫下降)에 미치는 영향(影響))

  • Hong, Sa-Ack;Cho, Hang-Young;Hong, Soon-Keun
    • The Korean Journal of Pharmacology
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    • v.5 no.2
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    • pp.93-103
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    • 1969
  • Saponin, essential oil, fat oil and alkaloidal fraction were fractionated from the ethanol extract of fanax ginseng. Effect of each fraction of Panax ginseng upon the temperature response induced by reserpine, chlorpromazine and nembutal was investigated in mice, so as to secure some hidden facets of each fraction of Panax ginseng acting upon central nervous system. The authors could arrive at some results, that is: (1) Inhibitory effect of Panax ginseng upon temperature decline induced by nembutal and chlorpromazine and potentiating action upon hyperthermia induced by reserpine reside mainly in saponin fraction and slightly in essential oil fraction. (2) The effect of Ginseng saponin on temperature response in nice seems to be related with the liberation of serotonin and histamine.

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Radiation induced grain boundary segregation in ferritic/martensitic steels

  • Xia, L.D.;Ji, Y.Z.;Liu, W.B.;Chen, H.;Yang, Z.G.;Zhang, C.;Chen, L.Q.
    • Nuclear Engineering and Technology
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    • v.52 no.1
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    • pp.148-154
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    • 2020
  • The radiation induced segregation of Cr at grain boundaries (GBs) in Ferritic/Martensitic steels was modeled assuming vacancy and interstitialcy diffusion mechanisms. In particular, the dependence of segregation on temperature and grain boundary misorientation angle was analyzed. It is found that Cr enriches at grain boundaries at low temperatures primarily through the interstitialcy mechanism while depletes at high temperatures predominantly through the vacancy mechanism. There is a crossover from Cr enrichment to depletion at an intermediate temperature where the Cr:Fe vacancy and interstitialcy diffusion coefficient ratios intersect. The bell-shape Cr enrichment response is attributed to the decreasing void sinks inside the grains as temperature rises. It is also shown that low angle grain boundaries (LAGBs) and special Σ coincidence-site lattice (CSL) grain boundaries exhibit suppressed radiation induced segregation (RIS) response while high angle grain boundaries (HAGBs) have high RIS segregation. This different behavior is attributed to the variations in dislocation density at different grain boundaries.

Tyrosine Kinase is Involved in Hemin-Induced Pyresis

  • Lee, Sang-Ho;Jang, Choon-Gon;Lee, Seok-Yong
    • Archives of Pharmacal Research
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    • v.26 no.5
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    • pp.411-415
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    • 2003
  • To investigate the mechanisms involved in hemin-induced febrile response, the rectal temperature of rats were measured after intracerebroventricular (i.c.v.) injections of hemin, with or without antagonists. Hemin ($10\mu\textrm{g}$) elicited a significant febrile response, which lasted from 30 min, to more than 6 h, after its administration, but this was not the case with biliverdin (i.c.v.) and bilirubin (i.c.v.). The hemin-induced febrile response was significantly inhibited by pretreatment with an inhibitor of tyrosine kinase (genistein), but not by pretreatment with an inhibitor of protein kinase C (chelerythrine) and a scavenger of iron (deferoxamine). These results suggest that tyrosine kinase is involved in the hemin-induced febrile response.

Nonlinear boundary parameter identification of bridges based on temperature-induced strains

  • Wang, Zuo-Cai;Zha, Guo-Peng;Ren, Wei-Xin;Hu, Ke;Yang, Hao
    • Structural Engineering and Mechanics
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    • v.68 no.5
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    • pp.563-573
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    • 2018
  • Temperature-induced responses, such as strains and displacements, are related to the boundary conditions. Therefore, it is required to determine the boundary conditions to establish a reliable bridge model for temperature-induced responses analysis. Particularly, bridge bearings usually present nonlinear behavior with an increase in load, and the nonlinear boundary conditions cause significant effect on temperature-induced responses. In this paper, the bridge nonlinear boundary conditions were simulated as bilinear translational or rotational springs, and the boundary parameters of the bilinear springs were identified based on the measured temperature-induced responses. First of all, the temperature-induced responses of a simply support beam with nonlinear translational and rotational springs subjected to various temperature loads were analyzed. The simulated temperature-induced strains and displacements were assumed as measured data. To identify the nonlinear translational and rotational boundary parameters of the bridge, the objective function based on the temperature-induced responses is then created, and the nonlinear boundary parameters were further identified by using the nonlinear least squares optimization algorithm. Then, a beam structure with nonlinear translational and rotational springs was simulated as a numerical example, and the nonlinear boundary parameters were identified based on the proposed method. The numerical results show that the proposed method can effectively identify the parameters of the nonlinear boundary conditions. Finally, the boundary parameters of a real arch bridge were identified based on the measured strain data and the proposed method. Since the bearings of the real bridge do not perform nonlinear behavior, only the linear boundary parameters of the bridge model were identified. Based on the bridge model and the identified boundary conditions, the temperature-induced strains were recalculated to compare with the measured strain data. The recalculated temperature-induced strains are in a good agreement with the real measured data.

Effects of stress induced by changes of water temperature on the non-specific defense mechanism in cultured olive flounder, Paralichthys olivaceus (수온 변동 자극이 양식 넙치, Paralichthys olivaceus의 비특이적 생체 방어에 미치는 영향)

  • Lee, Deok-Chan;Kim, Do-Hyung;Kim, Su-Mi;Kang, Myong-Seok;Hong, Mi-Ju;Kim, Hyun-Jeong;Park, Soo-Il
    • Journal of fish pathology
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    • v.15 no.2
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    • pp.65-75
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    • 2002
  • This study was performed to know the effects of stress induced by the daily fluctuation of water temperture from 18$^{\circ}C$ to 25$^{\circ}C$ up and down for 30 days on the defence mechanism of olive flounder. Puralichthys olivaceus. To make clear the temperature stress on the defense mechanism of the tested fish. several factors of immune response such as counting of leucocyte appearance in peripheral blood, phagocytic activity in whole blood cells, nitroblue tetrazolium(NBT) reduction, chemiluminescence(CL) response, and lysozyme activity were investigated at 28 days after giving the change of water temperature. The fish was controlled under the none feeding condition during experimental period. Mortality of the tested fish was rapidly increased up to 22% within the first one week of the experimental period without any additional stress factors. The number of neutrophil of peripheral blood in the tested group was significantly higher than the control group at the 2nd week. but the number of lymphocyte was significantly lower than the control group at the 1st and 3rd day of the experimental period. respectively. In the NBT reduction test, the activity of macrophage in the control group fish was the highest on the 7th day while that in the tested group was on the 3rd day. Also. the phagocytosis of tested group against formalin killed cells was retarded compared with the control. CL response of the tested group was significantly lower from 2nd to 5lh day of the experimental period than the control. 'The lysozyme activity of tested group was remained higher during the experimental period than the control. Even though the tested fish showed different results in some non-specific factors of immune respceses between tested and control group fish, olive flounder seems highly adaptable in repealed water temperature change in condition after one week under the given temperature fluctuation range.