• Title/Summary/Keyword: Harms technique

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Rod Migration into the Posterior Fossa after Harms Operation : Case Report and Review of Literatures

  • Chun, Hyoung-Joon;Bak, Koang-Hum;Kang, Tae-Hoon;Yi, Hyeong-Joong
    • Journal of Korean Neurosurgical Society
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    • v.47 no.3
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    • pp.221-223
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    • 2010
  • C1 lateral mass and C2 pedicle (C1LM-C2P) fixation is a relatively new technique for atlantoaxial stabilization. Complications from C1LM-C2P fixation have been rarely reported. The authors report unilateral rod migration into the posterior fossa as a rare complication after this posterior C1-C2 stabilization technique. A 23-year-old man suffered severe head trauma and cervical spine injury after vehicle accident. He was unconscious for 2 months and regained consciousness. He underwent C1LM-C2P fixation for stabilization of type II odontoid process fracture described by Harms. The patient recovered without a major complication. Twenty months after operation, brain computed tomogram performed at psychology department for disability evaluation showed rod migration into the right cerebellar hemisphere. The patient had mild occipital headache and dizziness only regarding the misplaced rod. He refused further operation for rod removal. To our knowledge, this complication is the first report regarding rod migration after Harms method. We should be kept in mind the possibility of rod migration, and C1LM-C2P fixation should be performed with meticulous technique and long-term follow-up.

Troublesome Occipital Neuralgia Developed by C1-C2 Harms Construct

  • Rhee, Woo-Tack;You, Seung-Hoon;Kim, Suk-Kyoung;Lee, Sang-Youl
    • Journal of Korean Neurosurgical Society
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    • v.43 no.2
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    • pp.111-113
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    • 2008
  • Recently, Harms and Melcher modified Goel's approach, the C1 lateral mass and C2 pedicle screw fixation, and the new technique is currently in favor among neurosurgeons. Comparing to the advantages of Harms construct, the disadvantages were not extensively investigated. We experienced a patient with severe occipital pain developed after the C1 lateral mass screw placement for the traumatic atlantoaxial instability. We reviewed literatures about Harms construct with focus on the occipital neuralgia as a postoperative complication and suggest here technical tips to avoid the troublesome pain.

Chemical Constituents from Leaves of Acanthopanax henryi (II)

  • Li, Zhi;Li, Xiao Jun;Kwon, Ok Kyoung;Wang, Xiang;Zou, Qin Peng;Liu, Xiang Qian;Lee, Hyeong kyu
    • Natural Product Sciences
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    • v.21 no.3
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    • pp.196-204
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    • 2015
  • Nineteen compounds, including one organic acid (1), one anthraquinone (2), one amide (3), and sixteen triterpenoid saponins (4 - 19) were isolated from the leaves of Acanthopanax henryi (Oliv.) Harms (Araliaceae). Their structures were determined on the basis of physicochemical properties and spectral analyses (HR-MS and NMR). Among them, compounds 2, 3, 7, 12 and 19 were new within Araliaceae. Compounds 4, 5, 9 - 11, 13, 14, 16 and 18 were reported for the first time from the Acanthopanax genus. Except for compounds 4 and 9, other compounds were isolated from A. henryi (Oliv.) Harms for the first time. The rare anthraquinone, compound 2, significantly decreased the production of NO and the levels of other inflammatory factors, such as TNF-α and IL-6, in lipopolysaccharide (LPS)-stimulated macrophages in a dose-dependent manner. This is the first time to report anti-inflammatory effect of this compound.

Modal Nodal Transport Analysis

  • Johnson, R.Douglas
    • Nuclear Engineering and Technology
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    • v.3 no.3
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    • pp.121-128
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    • 1971
  • A unified modal-nodal expansion of tile angular distribution of neutron flux in one spatial dimension is considered, following the proposal of Harms. Several standard nodal and/or modal methods of analysis are shown to be specializations of this technique. The modal-nodal moment from of the mono-energetic transport equation with isotropic sources and scattering is derived and the infinite medium eigenvalue problem solved. The technique is shown to yield results which approximate the exact value of the inverse diffusion length in non-multiplying media more accurately than standard methods of equal or somewhat greater computational complexity.

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Fuzzy Control Strategy for Damping Sub-Synchronous Resonance

  • Qader, M.R.
    • Journal of Electrical Engineering and Technology
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    • v.13 no.5
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    • pp.1791-1797
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    • 2018
  • Sub-Synchronous Resonance (SSR) is a phenomenon that harms turbine generator shafts because the phenomenon induces sub-synchronous wavering in the system. In the study presented in this paper, a dynamic resistance bank is used to mitigate the occurrence of sub-synchronous phenomenon. A fuzzy logic controller using rotor speed deviation and its derivative as inputs is implemented to damp sub-synchronous oscillations more efficiently. An eigenvalue technique is used to analyse the stability of the system, and a simulation in MATLAB is conducted, based on the IEEE Second Benchmark, to validate the effectiveness of the proposed method under a 3-phase fault condition at an infinite bus. The time-domain simulation and eigenvalues are used to observe the proposed method's superior ability to damp sub-synchronous oscillation.

A spectrum based evaluation algorithm for micro scale weather analysis module with application to time series cluster analysis (스펙트럼분석 기반의 미기상해석모듈 평가알고리즘 제안 및 시계열 군집분석에의 응용)

  • Kim, Hea-Jung;Kwak, Hwa-Ryun;Kim, Yu-Na;Choi, Young-Jean
    • Journal of the Korean Data and Information Science Society
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    • v.26 no.1
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    • pp.41-53
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    • 2015
  • In meteorological field, many researchers have tried to develop micro scale weather analysis modules for providing real-time weather information service in the metropolitan area. This effort enables us to cope with various economic and social harms coming from serious change in the micro meteorology of a metropolitan area due to rapid urbanization such as quantitative expansions in its urban activity, growth of population, and building concentration. The accuracy of the micro scale weather analysis modules (MSWAM) directly related to usefulness and quality of the real-time weather information service in the metropolitan area. This paper design a evaluation system along with verification tools that sufficiently accommodate spatio-temporal characteristics of the outputs of the MSWAM. For this we proposes a test for the equality of mean vectors of the output series of the MSWAM and corresponding observed time series by using a spectral analysis technique. As a byproduct, a time series cluster analysis method, using a function of the test statistic as the distance measure, is developed. A real data application is given to demonstrate the utility of the method.