• Title/Summary/Keyword: lateral stress

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Differential Effects of Minocycline on Caspase- and Calpain-dependent Cell Death After Oxidative Stress

  • Choi, Yu-Keum;Kim, Gap-Seok;Han, Byung-Hee
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2003.11a
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    • pp.67-67
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    • 2003
  • Minocycline is known to protect neurons from microglia-mediated cell death in many experimental models of brain diseases including ischemic stroke, Huntingtons disease (HD), amyotrophic lateral sclerosis (ALS), traumatic brain injury, multiple sclerosis, and Parkinsons disease. When the activity of caspases was assessed using their fluorescent peptide substrates, activation of caspase-2, 3, 8, and 9 was evident within 2 8 hr following oxidative insult with 0.5 mM hydrogen peroxide in PC12 cells. Minocycline significantly attenuated activation of these caspases up to 18 hr, resulting a significant increase in the cell viability as assessed by MTT assay as well as trypan blue staining. However, cleavage of alpha-spectrin and a cdk5 activator p35, which are known to be substrates for calpain, remained unchanged in the presence of minocycline, suggesting that minocycline did not block caspase-3-independent cell death or necrosis. Moreover, co-treatment with minocycline and a calpain inhibitor calpeptin synergistically inhibited hydrogen peroxide-induced cell death. These data suggest that minocycline directly inhibited apoptosis, but not necrosis, after oxidative insult in PC12 cells.

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Experimental study on simplified steel reinforced concrete beam-column joints in construction technology

  • Teraoka, Masaru;Morita, Koji;Sasaki, Satoshi;Katsura, Daisuke
    • Steel and Composite Structures
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    • v.1 no.3
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    • pp.295-312
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    • 2001
  • The purpose of this paper is to propose a new type of steel reinforced concrete (SRC) beam-column joints and to examine the structural performance of the proposed joints, which simplify the construction procedure of steel fabrication, welding works, concrete casting and joint strengthening. In the proposed beam-column joints, the steel element of columns forms continuously built-in crossing of H-sections (${\Box}$), with adjacent flanges of column being connected by horizontal stiffeners in a joint at the level of the beam flanges. In addition, simplified lateral reinforcement (${\Box}$) is adopted in a joint to confine the longitudinal reinforcing bars in columns. Experimental and analytical studies have been carried out to estimate the structural performance of the proposed joints. Twelve cruciform specimens and seven SRC beam-column subassemblage specimens were prepared and tested. The following can be concluded from this study: (1) SRC subassemblages with the proposed beam-column joints show adequate seismic performances which are superior to the demand of the current code; (2) The yield and ultimate strength capacities of the beam-to-column connections can be estimated by analysis based on the yield line theory; (3) The skeleton curves and the ultimate shear capacities of the beam-column joint panel are predicted with a fair degree of accuracy by considering a simple stress transfer mechanism.

Vibrational characteristics of multi-phase nanocomposite reinforced circular/annular system

  • Zhou, Changlin;Zhao, Yi;Zhang, Ji;Fang, Yuan;Habibi, Mostafa
    • Advances in nano research
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    • v.9 no.4
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    • pp.295-307
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    • 2020
  • The vibrational characteristics of Multi-Phase Nanocomposite (MPC) reinforced annular/circular plate under initially stresses are presented using the state-space formulation based on three-dimensional elasticity theory (3D-elasticity theory) and Differential Quadrature Method (DQM). The MPC reinforced annular/circular plate is under initial lateral stress and composed of multilayers with Carbon Nanotubes (CNTs) uniformly dispersed in each layer, but its properties change layer-by-layer along the thickness direction. The State-Space based Differential Quadrature Method (SS-DQM) is presented to examine the frequency behavior of the current structure. Halpin-Tsai equations and fiber micromechanics are used in the hierarchy to predict the bulk material properties of the multi-scale composite. A singular point is investigated for modeling the circular plate. The CNTs are supposed to be randomly oriented and uniformly distributed through the matrix of epoxy resin. Afterward, a parametric study is done to present the effects of various types of sandwich circular/annular plates on frequency characteristics of the MPC reinforced annular/circular plate using 3D-elasticity theory.

Improvement on Moment Resistance of a Concealed Timber Post Base Joint

  • Humbert, Jerome;Lee, Sang-Joon;Park, Joo-Saeng;Park, Moon-Jae
    • Journal of the Korea Furniture Society
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    • v.24 no.4
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    • pp.444-451
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    • 2013
  • In this paper, experimental results were presented on the moment resistance of a concealed timber post base joint aimed at replacing in a modern design introduced lately the wood to wood joints used in the traditional Korean timber house - Hanok. Preliminary results showed that the original configuration of the joint offers a limited moment resistance and a low ductility and energy dissipation. In an attempt to mitigate those limitations without undergoing major changes in the connector, three new configurations were proposed and investigated. Motivated by the wish to prevent the early failure in welds, a first approach consists in directly bolting the connector's upper plate to lower the stress on the weak welds. Alternatively, another approach focused on increasing the strength of these welds by extending their length to the full width of the metal wings. Finally, a third configuration investigated the effect of those two approaches combined. In conclusion, reinforcing the welds found out to be the best option among the presented ones. As a result, this connector considered to show proper ability for use in earthquake-resistant structures with suited lateral-resistant structural elements.

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Evaluation of Structural Performance of RC T-shaped Walls with Different ratios of axial load and vertical reinforcement (압축력비와 수직철근비에 따른 RC T형 벽체의 구조성능 평가에 관한 해석적 연구)

  • 하상수;최창식;이리형
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.05a
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    • pp.403-408
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    • 2003
  • The objective of this study is to understand the variables affected the confinement for the transverse reinforcement of the reinforced concrete structural walls with the T-shaped cross section subjected to cyclic lateral loads. The structural performance of T-shaped walls was advanced by the transverse reinforcement which restrained the concrete subjected to compressive stress. If the arrangement of transverse reinforcement was not suitable for the confinement, T-shaped walls happened the brittle failure by web crushing or bucking of vertical reinforcement at the compression zone. It is necessary to confine transverse reinforcement in order to prevent the these failure. But the location of neutral axis and the magnitude of ultimate strain vary according to the section shape, a ratio of axial load, a ratio of wall cross sectional area to the floor-plan area, an aspect ratio and the reinforcement ratio. Therefore, the objective of this research is to grasp the location of neutral axis and the range which needs for the confinement of transverse reinforcement through the results of the sectional analysis which varies the ratio of axial load and the ratio of vertical reinforcement.

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Non-stationary mixed problem of elasticity for a semi-strip

  • Reut, Viktor;Vaysfeld, Natalya;Zhuravlova, Zinaida
    • Coupled systems mechanics
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    • v.9 no.1
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    • pp.77-89
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    • 2020
  • This study is dedicated to the dynamic elasticity problem for a semi-strip. The semi-strip is loaded by the dynamic load at the center of its short edge. The conditions of fixing are given on the lateral sides of the semi-strip. The initial problem is reduced to one-dimensional problem with the help of Laplace's and Fourier's integral transforms. The one-dimensional boundary problem is formulated as the vector boundary problem in the transform's domain. Its solution is constructed as the superposition of the general solution for the homogeneous vector equation and the partial solution for the inhomogeneous vector equation. The matrix differential calculation is used for the deriving of the general solution. The partial solution is constructed with the help of Green's matrix-function, which is searched as the bilinear expansion. The case of steady-state oscillations is considered. The problem is reduced to the solving of the singular integral equation. The orthogonalization method is applied for the calculations. The stress state of the semi-strip is investigated for the different values of the frequency.

Compressive behavior of rectangular sandwich composite wall with different truss spacings

  • Qin, Ying;Chen, Xin;Xi, Wang;Zhu, Xing-Yu;Chen, Yuan-Ze
    • Steel and Composite Structures
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    • v.34 no.6
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    • pp.783-794
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    • 2020
  • Steel-concrete-steel sandwich composite wall is composed of two external steel plates and infilled concrete core. Internal mechanical connectors are used to enhance the composite action between the two materials. In this paper, the compressive behavior of a novel sandwich composite wall was studied. The steel trusses were applied to connect the steel plates to the concrete core. Three short specimens with different truss spacings were tested under compressive loading. The boundary columns were not included. It was found that the failure of walls started from the buckling of steel plates and followed by the crushing of concrete. Global instability was not observed. It was also observed that the truss spacing has great influence on ultimate strength, buckling stress, ductility, strength index, lateral deflection, and strain distribution. Three modern codes were introduced to calculate the capacity of walls. The comparisons between test results and code predictions show that AISC 360 provides significant underestimations while Eurocode 4 and CECS 159 offer overestimated predictions.

Experimental and analytical performance evaluation of steel beam to concrete-encased composite column with unsymmetrical steel section joints

  • Xiao, Yunfeng;Zeng, Lei;Cui, Zhenkun;Jin, Siqian;Chen, Yiguang
    • Steel and Composite Structures
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    • v.23 no.1
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    • pp.17-29
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    • 2017
  • The seismic performance of steel beam to concrete-encased composite column with unsymmetrical steel section joints is investigated and reported within this paper. Experimental and analytical evaluation were conducted on a total of 8 specimens with T-shaped and L-shaped steel section under lateral cyclic loading and axial compression. The test parameters included concrete strength, stirrup ratio and axial compression ratio. The response of the specimens was presented in terms of their hysterisis loop behavior, stress distribution, joint shear strength, and performance degradation. The experiment indicated good structural behavior and good seismic performance. In addition, a three-dimensional nonlinear finite-element analysis simulating was conducted to simulate their seismic behaviors. The finite-element analysis incorporated both bond-slip relationship and crack interface interaction between steel and concrete. The results were also compared with the test data, and the analytical prediction of joint shear strength was satisfactory for both joints with T-shaped and L-shaped steel section columns. The steel beam to concrete-encased composite column with unsymmetrical steel section joints can develop stable hysteretic response and large energy absorption capacity by providing enough stirrups and decreased spacing of transverse ties in column.

Clinical Assessment of Temporomandibular Joint Dysfunction (측두하악 관절 장애의 평가)

  • Ryoo, Jae-Kwan;Kim, Jong-Soon
    • Journal of Korean Physical Therapy Science
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    • v.5 no.4
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    • pp.717-728
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    • 1998
  • The Temporomandibural joint(TMJ) is one of the most frequently used joint in the body as $1,500{\sim}2,000$ times per day for the activities of chewing, swallowing, talking, yawing and sneezing. The TMJ are formed by condylar process of mandible and mandible fossa of temporal bone, separated by an articular disc. This articular disc divides into two cavities as upper cavity and lower cavity. The gliding movement occurs in the upper cavity of the joint, whereas hinge movement occurs in the lower cavity. The movements that are allowed at the TMJ are opening, closing, protrusion, retraction and lateral movement. A cause of TMJ dysfunction are capsulitis, internal derangement, osteoarthritis, rheumatoid arthritis, infection and inflammation near the joint, trauma on joint, ankylosis, subluxation or dislocation of joint, injury of articular disc, myositis, muscle contracture or spasm, myofascial pain dysfunction syndrome, dyskinesia of masticatory muscles, developmental abnormality, tumor, connective tissue disease, fibrosis, malocclusion, swallowing abnormality, wrong habits such as bite nail or hair, bruxism, psycological stress and Costen syndrome etc. Assessment of TMJ dysfunction consist of interview, observation, functional examination, palpation, reflex test, joint play test, electromyography and radiologic examination and behavioral and psycological assessment etc.

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A Clinical Process Report on the Patient Suffered from Flank Pain after CVA Treated with Shihosogansna (시호소간산(柴胡疏肝散)이 투여(投與)된 중풍(中風) 이후(以後) 병발(倂發)한 협통환자(脇痛患者)의 임상경과보고(臨床經過報告))

  • Park Mee-Yeon;Kim Dae-Jun;Choi Hae-Yun;Kim Jong-Dae
    • The Journal of Internal Korean Medicine
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    • v.24 no.1
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    • pp.144-150
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    • 2003
  • Back pains include pain in one or both side costa portion and lateral abdomen. There are different kinds of flank-related disease such as intercostal nerve pain, chronic gastritis, duodenitis, herpes zoster, pepticulcer, cholecystitis, cholelithiasis and so on. Back pain arises from pathological abnormal activities. On the other hand psychogenic pains are caused by psychogenic factors without pathological abnormal activities. This is similar to KiWol back pain, which resulted from psychogenic factors like stress, anxiety, anger and etc. In oriental medicine, KiWol is the state of depression of Ki, and Shihosogansan used to treat the back pain diagnosed as stagnation of the liver Ki. So, we decided to apply Shihosogansan to a patient who suffered from back pain diagnosed as stagnation of the liver Ki. Therefore the patient treated with Shihosogansan and improved in consciousness symptoms, so we report it for the better treatment.

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