• 제목/요약/키워드: Bennett model

검색결과 13건 처리시간 0.02초

신경결찰로 인한 이질통에서 Metabotrophic Glutamate 5형 수용체의 변화에 대한 연구 (The Changes of Metabotrophic Glutamate Receptor Type 5 in Allodynia Induced by Nerve Ligation)

  • 이윤우
    • The Korean Journal of Pain
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    • 제12권1호
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    • pp.8-15
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    • 1999
  • Following peripheral nerve injury, rats will show a tactile allodynia and hyperalgesia. But the mechanism of allodynia is still obscure. The present studies, using rats rendered allodynia by loosely constrictive ligation of the common sciatic nerve (Bennett Model) and tight ligation of L5 & L6 spinal nerve (Chung Model), aimed to investigate the changes of metabotrophic glutamate receptor type 5 on the development of tactile allodynia. Male Sprague-Dawley rats (130~200 g) were anesthetized with halothane, the rats were randomly divided into one of these three groups, Group 1 (Sham operation), Group 2 (Bennett model) and Group 3 (Chung model). Seven days after surgical procedure, the animal was reanesthetized and decapitated. The spinal cord was quickly removed and stored at deep freezer for polymerase chain reaction (RT-PCR). In Group 2&3, rats showed that tactile allodynia checked by up-down method with calibrated 8 von Frey hair. The level of gene expression of mGluR5 mRNA was significantly increased in group 2 and 3. These increases was significantly different from sham operation, group 1. It was also showed that the increasing patterns of group 2 and 3 in the gene expression were similar correlation with the results of the threshold for tactile allodynia on von Frey hair test. Even though there were some differences between Bennett model and Chung model, these results suggested that mGluR5 had partly attributed to making a tactile allodynia from these models.

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한국 다문화교육의 연구동향 분석 : Bennett이론에 근거하여 (Analysis of multicultural education research trends in Korea)

  • 장인실;차경희
    • 한국교육학연구
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    • 제18권1호
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    • pp.283-302
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    • 2012
  • 한국에서 다문화가정이 정착하기 시작한 시기는 1980년대 후반부터이지만, 본격적으로 다문화교육에 대한 논의가 시작된 것은 2000년대 중반 이후이다. 다문화교육에 대한 국내 연구는 최근 들어 매우 다양한 각도에서 활발하게 진행되고 있지만 전체적이고 포괄적인 분석이 뒤따르지 않는 실정이다. 본 연구에서는 한국 다문화교육의 연구 동향과 특징을 파악하기 위하여 한국연구재단 등재와 등재후보 학술지에 게재된 다문화교육 관련 논문 302편을 분석하였다. 분석은 시기별 연구동향, 연구범주 및 연구대상, 연구주제별로 실시되었다. 특히 연구주제 분석은 Bennett이 제시한 다문화교육의 네 가지 핵심 영역- 평등교육, 교육과정개혁, 다문화적 역량, 사회정의-에 근거하여 이루어졌다. Bennett의 각 영역별 3개씩의 하위영역 범주에 의한 논문 분석 과정에서 추가로 추출해낸 5개의 한국적 범주인 다문화주의, 외국의 다문화교육, 상담연구, 척도개발, 시민교육이 추가되어 연구의 분석틀로 사용되었다. 마지막으로 본 연구의 분석 결과를 바탕으로 한국 다문화교육 연구에 대한 제언을 탐색하였다.

말초신경손상이 척수후근신경절 및 척수에서 Brain-derived neurotrophic factor 발현에 미치는 양상 (Patterns of the peripheral nerve injury on expression of brain-derived neurotrophic factor in dorsal root ganglia and spinal cord in rats)

  • 하선옥;홍해숙
    • Journal of Korean Biological Nursing Science
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    • 제4권1호
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    • pp.101-112
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    • 2002
  • Peripheral nerve injury results in plastic changes in the dorsal ganglia (DRG) and spinal cord, and is often complicated with neuropathic pain. The mechanisms underlying these changes are not known, but these changes seem to be most likely related to the neurotrophic factors. This study investigated the effects of mechanical peripheral nerve injury on expression of brain-derived neurotrophic factor(BDNF) in the DRG and spinal cord in rats. 1) Bennett model and Chung model groups showed significantly increased percentage of small, medium and large BDNF-immunoreactive neurons in the ipsilateral $L_4$ DRG compared with those in the contralateral side at 1 and 2 weeks of the injury. 2) In the ipsilateral $L_5$ DRG of the Chung model, percentage of medium and large BDNF-immunoreactive neurons increased significantly at 1 week, whereas that of large BDNF-immunoreactive neurons decreased at 2 week when compared with those in the contralateral side. The intensity of immunoreactivity of each neuron was lower in the ipsilateral than in the contralateral DRG. 3) In the spinal cord, the Bennett and Chung model groups showed a markedly increased BDNF-immunoreactivity in axonal fibers of both superficial and deeper laminae. The present study demonstrates that peripheral nerve injury in neuropathic models altered the BDNF expression in the DRG and spinal cord. This may suggest important roles of BDNF in sensory abnormalities after nerve injury and in protecting the large-sized neurons in the damaged DRG.

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Application of computers to Cave Surveying

  • Bennett, A.J.
    • 동굴
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    • 제5호
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    • pp.96-106
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    • 1997
  • The reduction of cave survey data is an essentially straightforward but repetitive mathematical task which can be carried out to advantage using virtually any type of computer from a programmable calculator upwards. The obvious benefits are speed and accuracy in reducing and adjusting the raw data to obtain the x,y,z coordinates (eastings, northings and elevations) of the surveyed points. Additionally, depending on the functionality of the software (program) and power of the hardware (computer), the user may be able to build up a data base of surveys, plot out on paper scaled plans and elecations of the cave and possibly even see a three-dimensional model of the cave, in perspective or some other projection, as an aid to understanding the spatial relationships of cave passages.(omitted)

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Drosophila melanogaster as a Model for Studying Aspergillus fumigatus

  • AL-Maliki, Hadeel Saeed;Martinez, Suceti;Piszczatowski, Patrick;Bennett, Joan W.
    • Mycobiology
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    • 제45권4호
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    • pp.233-239
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    • 2017
  • Drosophila melanogaster is a useful model organism that offers essential insights into developmental and cellular processes shared with humans, which has been adapted for large scale analysis of medically important microbes and to test the toxicity of heavy metals, industrial solvents and other poisonous substances. We here give a brief review of the use of the Drosophila model in medical mycology, discuss the volatile organic compounds (VOCs) produced by the opportunistic human pathogen, Aspergillus fumigatus, and give a brief summary of what is known about the toxicity of some common fungal VOCs. Further, we discuss the use of VOC detection as an indirect indicator of fungal growth, including for early diagnosis of aspergillosis. Finally, we hypothesize that D. melanogaster has promise for investigating the role of VOCs synthesized by A. fumigatus as possible virulence factors.

Selection of features and hidden Markov model parameters for English word recognition from Leap Motion air-writing trajectories

  • Deval Verma;Himanshu Agarwal;Amrish Kumar Aggarwal
    • ETRI Journal
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    • 제46권2호
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    • pp.250-262
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    • 2024
  • Air-writing recognition is relevant in areas such as natural human-computer interaction, augmented reality, and virtual reality. A trajectory is the most natural way to represent air writing. We analyze the recognition accuracy of words written in air considering five features, namely, writing direction, curvature, trajectory, orthocenter, and ellipsoid, as well as different parameters of a hidden Markov model classifier. Experiments were performed on two representative datasets, whose sample trajectories were collected using a Leap Motion Controller from a fingertip performing air writing. Dataset D1 contains 840 English words from 21 classes, and dataset D2 contains 1600 English words from 40 classes. A genetic algorithm was combined with a hidden Markov model classifier to obtain the best subset of features. Combination ftrajectory, orthocenter, writing direction, curvatureg provided the best feature set, achieving recognition accuracies on datasets D1 and D2 of 98.81% and 83.58%, respectively.

불규칙파의 유공 케이슨 방파제로부터의 반사율 산정시 규칙파 모델 적용 (Application of a Regular Wave Model to Calculation of Irregular Wave Reflection from Perforated-Wall Caisson Breakwaters)

  • 서경덕;손상영
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2002년도 학술대회지
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    • pp.205-208
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    • 2002
  • Numerous studies have been performed to develop an analytical model that can predict the reflection of regular or irregular waves from a perforated-wall caisson breakwater. Though such irregular wave models as Suh et at. (2001) become available, regular wave models are still in extensive use because of their simplicity. In the present study, using the regular wave model of Fuggazza and Natale(1992), the reflection of irregular waves from a perforated-wall caisson breakwater was calculated in several different methods. First, the regular wave model was re-validated by the hydraulic model tests. Though the model somewhat over-predicted the reflection coefficients at larger values and under-predicted them at smaller values, overall agreement was pretty good between calculation and measurement. Then, the regular wave model was applied to calculate the irregular wave reflection in the experiments of Suh et at.(2001) and Bennett et al. (1992). In applying the regular wave model to irregular wave reflection, several different methods were used. The results showed that it is the most reasonable to use the regular wave model repeatedly for each frequency component of the irregular wave specuum with the root-mean-squared wave height for all the frequencies .

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Three dimensional finite element simulations of fracture tests using the Craft concrete model

  • Jefferson, A.D.;Barr, B.I.G.;Bennett, T.;Hee, S.C.
    • Computers and Concrete
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    • 제1권3호
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    • pp.261-284
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    • 2004
  • Two enhancements to a recently developed plastic-damage-contact model for concrete are presented. The model itself, which uses planes of degradation that can undergo damage and separation but that can regain contact according to a contact law, is described. The first enhancement is a new damage evolution function which provides a completely smooth transition from the undamaged to the damaged state and from pre-peak to post-peak regions. The second is an improved contact function that governs the potential degree of contact with increasing opening on a crack plane. The use of a damage evolution function with a pre-peak has implications for the consistent tangent matrix/stress recovery algorithm developed for the model implementation, and amendments to this algorithm to accommodate the new function are described. A series of unpublished experimental tests on notched specimens undertaken in Cardiff in the mid 1990s are then described. These include notched beam tests as well as prismatic and cylindrical torsion tests. The tests are then considered in three dimensional finite element analyses using the modified Craft model implemented in the finite element program LUSAS. Comparisons between experimental and numerical data show reasonable agreement except that the numerical simulations do not fully describe the latter stages of the softening responses for the torsion examples. Finally, it is concluded that the torsion tests described provide useful benchmark examples for the validation of three-dimensional numerical models for concrete.

IMPLEMENTATION OF DATA ASSIMILATION METHODOLOGY FOR PHYSICAL MODEL UNCERTAINTY EVALUATION USING POST-CHF EXPERIMENTAL DATA

  • Heo, Jaeseok;Lee, Seung-Wook;Kim, Kyung Doo
    • Nuclear Engineering and Technology
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    • 제46권5호
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    • pp.619-632
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    • 2014
  • The Best Estimate Plus Uncertainty (BEPU) method has been widely used to evaluate the uncertainty of a best-estimate thermal hydraulic system code against a figure of merit. This uncertainty is typically evaluated based on the physical model's uncertainties determined by expert judgment. This paper introduces the application of data assimilation methodology to determine the uncertainty bands of the physical models, e.g., the mean value and standard deviation of the parameters, based upon the statistical approach rather than expert judgment. Data assimilation suggests a mathematical methodology for the best estimate bias and the uncertainties of the physical models which optimize the system response following the calibration of model parameters and responses. The mathematical approaches include deterministic and probabilistic methods of data assimilation to solve both linear and nonlinear problems with the a posteriori distribution of parameters derived based on Bayes' theorem. The inverse problem was solved analytically to obtain the mean value and standard deviation of the parameters assuming Gaussian distributions for the parameters and responses, and a sampling method was utilized to illustrate the non-Gaussian a posteriori distributions of parameters. SPACE is used to demonstrate the data assimilation method by determining the bias and the uncertainty bands of the physical models employing Bennett's heated tube test data and Becker's post critical heat flux experimental data. Based on the results of the data assimilation process, the major sources of the modeling uncertainties were identified for further model development.

외국어 교육과 문화 교육 통합을 위한 제언 (Suggestions for Integrating Foreign Language Teaching with Culture Education)

  • 김용섭
    • 한국콘텐츠학회논문지
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    • 제13권12호
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    • pp.1069-1078
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    • 2013
  • 이 논문은 언어수업에서 문화를 가르치는 것에 관한 것이다. 많은 교사들이 외국어를 가르치면서 동시에 문화를 가르치는 것을 부담스러워 하며 두려워하기까지 한다. 정치, 경제, 역사, 예술, 문학 등 객관적인 문화를 가르치는 것을 두려워하지는 않지만 의사소통능력과 관련된 문화인 주관적인 문화를 지도하는 것에는 난색을 표명한다. 본고에서는 언어수업에서 문화 지도를 할 수 있는 간단한 3단계 방법을 제안하고자 한다. 이는 Lange, Bennett 그리고 Moran의 방법을 혼합하여 재구성한 방법이다. 첫 번째 단계는 자기중심적 세계를 탈피하고 두 번째 단계는 자신의 문화와 목표 문화를 비교하여 문화에 대한 자각력을 키우고 세 번째 단계는 목표 문화에 적절히 반응하는 것이다. 교재는 영화를 사용한다. 영화 속에 나타난 문화적 양상이 일상과 관련된 주관적 문화이므로 언어수업에서 가르치고자 하는 문화와 일맥상통한다. 또한 영화는 학생들이 좋아하는 장르이므로 이점이 있다. 문화 교육을 위한 이 조그마한 제안이 나와 다른 인종들을 서로 이해하며 존경하는 세상이 오는 데 일익을 담당하기를 기대해 본다.