• Title/Summary/Keyword: 기계적 자극

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Inhibition of Articular Sensory Activities to Mechanical Stimulation by Aqua-acupuncture in an Animal Model of Arthritic Pain (관절통에 관한 동물모델에서 약침에 의한 기계적 자극에 대한 관절 감각신경 활동의 억제)

  • Shim In-Sop;Cho Hyung-Joon;Hahm Dae-Hyun;Lee Hye-Jung;Lee Bae-Hwan
    • Science of Emotion and Sensibility
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    • v.8 no.2
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    • pp.155-160
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    • 2005
  • The aim of this study was to examine the effects of aqua-acupuncture a mixture of bos taurus domesticus and selenarctos thiberanus, and bos taurus domesticus, selenarctos thiberanus and Moschus moschiferus on an animal model of arthritic pain. Under halothane anesthesia, arthritic pain was induced by the injection of $2\%$ carrageenan into the left knee joint cavity of male Sprague-Dawley rats. The responses of afferents to a movement cycle were recorded before and after aqua-acupuncture. The aqua-acupuncture at acupoints reduced neural responses to noxious movement stimulation. Aqua-acupuncture at Zusanli inhibited neural responses of articular afferents to noxious stimulation more than at Hegu. These results indicate that aqua-acupuncture of a mixture of bos taurus domesticus and selenarctos thiberanus, and bos taurus domesticus, selenarctos thiberanus and Moschus moschiferusmay provide a potent strategy in relieving arthritic pain.

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In situ Electric-Field-Dependent X-Ray Diffraction Experiments for Ferroelectric Ceramics (강유전 세라믹의 전기장 인가에 따른 in situ X-선 회절 실험)

  • Choi, Jin San;Kim, Tae Heon;Ahn, Chang Won
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.35 no.5
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    • pp.431-438
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    • 2022
  • In functional materials, in situ experimental techniques as a function of external stimulus (e.g., electric field, magnetic field, light, etc.) or changes in ambient environments (e.g., temperature, humidity, pressure, etc.) are highly essential for analyzing how the physical properties of target materials are activated/evolved by the given stimulation. In particular, in situ electric-field-dependent X-ray diffraction (XRD) measurements have been extensively utilized for understanding the underlying mechanisms of the emerging electromechanical responses to external electric field in various ferroelectric, piezoelectric, and electrostrictive materials. This tutorial article briefly introduces basic principles/key concepts of in situ electric-field-dependent XRD analysis using a lab-scale XRD machine. We anticipate that the in situ XRD method provides a practical tool to systematically identify/monitor a structural modification of various electromechanical materials driven by applying an external electric field.

Numerical Analysis for the Conjugate Heat Transfer of Skin Under Various Temperature Conditions of Contrast Therapy (냉온 자극의 다양한 온도경계조건들에 대한 피부 내 온도 분포의 수치해석)

  • Park, Da Ae;Oh, Han Nah;Jeon, Byoung Jin;Kim, Eun Jeong;Lee, Seung Deok;Choi, Hyoung Gwon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.39 no.11
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    • pp.897-903
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    • 2015
  • In this paper, the contrast therapy of skin was numerically investigated by solving the conjugate heat transfer problem. A finite volume method based on the SIMPLE algorithm was adopted to solve the axisymmetric incompressible Navier-Stokes equations, coupled with an energy equation. These equations are strongly coupled with the Pennes bio-heat equation in order to consider the effect of blood perfusion rate. We investigated the thermal response of skin at some selected depths for various input temperature profiles of a stimulator for contrast therapy. From the numerical simulations, the regions with cold/hot threshold temperatures were found for five input temperature profiles. It was shown that the temperature varies mildly for different input profiles as the depth increases, owing to the Pennes effect. The input temperatures for effective hot/cold stimulation of dermis layer were found to be $47^{\circ}C$ and $7^{\circ}C$, respectively. The present numerical results will be used for finding an optimal temperature profile of a stimulator for contrast therapy.

Cochlear Electrical Model for the Interpretation of Tinnitus Phenomenon (이명 현상의 해석을 위한 와우의 전기적 모델)

  • 이영주;이낙범;임재중;강희용
    • Journal of Biomedical Engineering Research
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    • v.22 no.1
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    • pp.91-99
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    • 2001
  • 청각기관에서 소리가 전달되어지는 과정에 대한 이론적인 전기/기계적 모델이 이루어진다면 이명환자의 분류 및 전기자극을 이용한 치료방법의 선택에 크게 기여할 수 있을 것이다. 본 연구에서는 기존 청각기관의 모델에 대한 장단점을 파악하여 이를 보완하는 실제의 시스템에 가장 근접한 모델을 수립하고, 청각시스템의 변화를 객관적으로 관찰할 수 있는 이론적인 배경을 수립하고자 하였다. 즉, 유모세포의 상면을 질량을 가진 성분으로 가정하고 그러한 질량의 경도와 제동을 위한 소자들을 첨가하여 새롭게 청각 모델을 수립하였다. 그리고 수립된 모델을 수학적으로 해석하여 전달함수의 영점이 극점보다 작게 나타남으로써 신경 조율 데이터를 이용한 기존의 연구와 일치함을 확인할 수 있었고, 제동주파수와 극점 주파수의 관계에 대한 가정들이 정당화됨을 확인할 수 있었다.

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The effect of progressive tensional force on mRNA expression of osteoprotegerin and receptor activator of nuclear factor ${\kappa}B$ ligand in the human periodontal ligament cell (기계적 자극이 치주인대 세포의 osteoprotegerin과 receptor activator of nuclear factor ${\kappa}B$ ligand mRNA 발현에 미치는 영향)

  • Lee, Kie-Joo;Lee, Syng-Ill;Hwang, Chung-Ju;Ohk, Seung-Ho;Tian, Yu-Shin
    • The korean journal of orthodontics
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    • v.35 no.4 s.111
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    • pp.262-274
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    • 2005
  • Tooth movement is a result of mutual physiologic responses between the periodontal ligament and alveolar bone stimulated by mechanical strain. The PDL cell and osteoblast are known to have an influence on bone formation by controlling collagen synthesis and alkaline phosphatase activation. Moreover. recent studies have shown that the PDL cell and osteoblast release osteoprotegerin (OPG) and the receptor activator of nuclear factor ぉ ligand (RANKL) to control the level of osteoclast differentiation and activation which in turn influences bone resorption. In this study. progressively increased, continuous tensional force was applied to PDL cells. The objective was to find out which kind of biochemical reactions occur after tensional force application and to illuminate the alveolar bone resorption and apposition mechanism. Continuous and progressively increased tensile force was applied to PDL cells cultured on a petriperm dish with a flexible membrane The amount of $PGE_2$ and ALP synthesis were measured after 1, 3, 0 and 12 hours of force application. Secondly RT-PCR analysis was carried out for OPG and RANKL which control osteoclast differentiation and MMP-1 -8, -9, -13 aud TIMP-1 which regulate the resolution of collagen and resorption of the osteoid layer According to the results. we concluded that progressively increased, concluded force application to human PDL cells reduces $PGE_2$ synthesis, and increases OPG mRNA expression.

Evaluation of Electric Pulp Test (EPT) as a Tool for Measurement of Dentinal Hypersensitivity (상아질 지각과민 측정 도구로서의 전기치수검사에 대한 평가)

  • Kim, Young-Sung
    • Journal of Periodontal and Implant Science
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    • v.32 no.2
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    • pp.371-378
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    • 2002
  • In this study, 40 hypersensitive teeth of 19 patients were investigated. The procedures performed were as follows: Before desensitization, EPT at occlusal third of buccal surface was done for the evaluation of pulp vitality and the EPT value was recorded for the reference value. And mechanical and thermal test was executed for the test of hypersensitivity. If the tooth responded to the above tests, we did EPT at the exposed surface, using toothpaste as a electrolite medium and recorded the EPT value at patient's response. After the tests had been done, desensitization procedures with Gluma(R) Desensitizer were performed according to the manufacturer's instructions. After desensitization, the same tests except EPT at occlusal third were repeated. All the 40 teeth responded positive before desensitization and negative after desensitization procedures. The EPT value at occlusal third ranged from 31 to 65 (48.9${\pm}$7.2). Before desensitization 34 teeth responded at EPT value of 2 and the remaining 6 teeth was in the range of 17 to 25. After desensitization all 40 teeth responded from 12 to 27 (19.6${\pm}$3.5). The 6 teeth responded at greater number than 2 before desensitization was in the range of 18 to 23. Within the limitations of this study we can conclude that: When a tooth with dentinal hypersensitivity responds to mechanical and thermal stimulation, the tooth shows very low resistance to electricity at the exposed surface while when a tooth is desensitized and doesn't show respond to mechanical and thermal stimuli, the tooth shows increased level of resistance to electric stimulation at the exposed surface. EPT can be used for the diagnosis of dentinal hypersensitivity. Furthermore EPT will be useful to evaluate the outcome of desensitization procedures. However, EPT is not a valid tool for measuring dentinal hypersensitivity.

Height Suppression of Cucumber and Tomato Plug Seedlings Using of Brushing Stimulus (브러싱 자극을 이용한 오이와 토마토 공정묘의 초장 억제)

  • Kim, Hyeon Min;Lee, Hye Ri;Jeong, Hyeon Woo;Kim, Hye Min;Hwang, Seung Jae
    • Journal of Bio-Environment Control
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    • v.27 no.4
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    • pp.285-293
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    • 2018
  • This study aimed to evaluate the effect of height suppression of cucumber and tomato plug seedlings as affected by mechanical stimulus using brushing as environment-friendly method. Cucumber (Cucumis sativus L. 'Joeunbaekdadagi') and tomato (Solanum lycopersicum L. 'Mini Chal') seeds were sown in 40-cell plug trays ($54{\times}27.5{\times}5cm$) filled with growing medium on Oct. 9, 2017. The cultivation environment in a venlo-type glasshouse was maintained as cultivation temperature range of $15-25^{\circ}C$ and the relative humidity of $50{\pm}10%$. Nontreatment and diniconazole ($7.5mg{\cdot}L^{-1}$) application at 15 days after sowing were used as the control. In addition, brushing treatments in cucumber and tomato were applied interval of 2, 4 or 6 hrs for 15 and 20 days, respectively. Plant height, hypocotyl length, and internode length were inhibited for cucumber and tomato in the diniconazole treatment than in the control. The leaf size was reduced, both cucumber and tomato, while the SPAD increased under the diniconazole treatment. However, stem diameter of cucumber was the thickest in the 2 hrs brushing interval treatment. Fresh weights of shoot and root were the significantly lowest in the diniconazole treatment. Application of brushing improved seedlings quality by promoting dry weights of shoot and root, and compactness of tomato seedlings. The chlorophyll fluorescence of tomato seedlings drastically decreased with 2 hrs treatment, indicating that mechanical stress by brushing treatment. The relative growth rate of tomato seedlings was significantly lower in the diniconazole treatment, but cucumber seedlings were not significantly different in all treatments. As a results, height suppression of cucumber and tomato seedlings was best achievement in the diniconazole treatment by the chemical as growth regulator. In an environment-friendly point of view, however, it is considered that 2 hrs brushing interval treatment can be the applicability for replacing the chemical methods in plug seedling growth of cucumber and tomato.

CLINICAL ANALYSIS OF THE VOCAL NODULE (성대결절의 임상적 고찰)

  • 김기령;김광문;현승재;전영명
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.2 no.1
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    • pp.24-30
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    • 1986
  • The vocal nodule is one of the major causes of hoarseness. The patholphysiologic mechanism of the vocal nodule is relatively well-known. Chronic mechanical stimuli, such as vocal abuse, causes vocal nodule by a tissue reaction of the vocal cords. Among the 841 patients, who visited the Vocal Dynamic Laboratory at Severance Hospital complaining of the dysphonia between the period of May 1981- May 1985, 169 patients were selected who were diagnosed as vocal nodule by indirect laryngoscopy and a series of phoniatric examination. (omitted)

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반복대신장시의 천연고무 가류물의 피로

  • DaeEum Hak;SangJin Im;ChonSang Sin-Ja
    • The tire
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    • s.65
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    • pp.3-9
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    • 1976
  • 가유 고무에 대변형의 반복왜를 외부자극으로서 부여하면 초기에는 대폭의 응력의 변화현상이 보여져 서서히 일정응력치에 접근하여 파단에 이른다. 이 응력의 변화현상과 피로수명(파단하기까지의 회수)이 여하한 기계적 화학적 인자의 영향을 받는가를 천연고무의 순고무 가유물로 검토했다. 그 결과 실온으로 고무에 반복신장피로를 부여하면 가교구조, 망목밀도 및 신장률이 응력변화의 대소, 피로수명의 증감에 영향을 주었다. 고온으로 고무에 반복신장피로를 주면 열산화에 의하여 어느 온도로부터 현저한 응력연화(화학응력연화) 현상이 보였다. 연이나 고무에 열화방지제를 첨가하면 고온에 있어서의 산화반응이 억제되기 때문에 무첨가의 경우와 달라서 파단이나 현저한 응력연화가 일어나지 않았다. 피로수명(F)와 파괴신장(εb),반복신장률(ε)사이에 F=A(εb-ε)n 의 관계가 성립함이 인정되었다. An은 고유의 파라메에터어이며 천연고무의 순고무가유물로서 n은 4.0~4.5의 거의 일정치를 표시했다.

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작업환경을 위한 TLV의 근거 - PHENOL(1)

  • Kim, Chi-Nyeon
    • 월간산업보건
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    • s.292
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    • pp.11-15
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    • 2012
  • 페놀의 작업 노출에 대한 TLV-TWA는 5ppm ($19mg/m^3$)으로 눈과 호흡기계의 자극과 함께 심장, 간, 신경 독성 영향을 최소화하기 위해 설정되었다. 페놀은 증기상과 액상 또는 고체상 형태로 피부에 접촉되면 흡수되어 심각한 계통 영향을 유발하여 최종적으로 사망에 이르게 한다. 피부를 통한 흡수율은 흡입에 의한 체내 흡수율과 거의 동일한 수준이다. 따라서 현재 Skin notation(피부흡수 경고) 물질로 지정되어 있다. 발암성 여부를 결정하기 위한 동물 실험 결과에서는 음성 또는 발암성을 판정하기에는 데이터가 부족한 관계로 A4로 지정되어 있다. 또한 SEN과 TLV-STEL도 유용한 자료의 부족으로 아직 설정되지 않고 있다. 페놀은 BEIs로 활용될 수 있는 기질 중 하나이다.

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