• Title/Summary/Keyword: Hutchinson

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Detection of Cerebrovascular Disease in a Child with Hutchinson-Gilford Progeria Syndrome Using MR Angiography: A Case Report (Hutchison-Gilford 조로증 증후군 환아에서의 뇌 자기공명 혈관조영술 소견: 증례 보고)

  • Jae Ho Lee;Ha Young Lee;Myung Kwan Lim;Young Hye Kang
    • Journal of the Korean Society of Radiology
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    • v.83 no.6
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    • pp.1360-1365
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    • 2022
  • Hutchinson-Gilford progeria syndrome (HGPS) is a rare, progressive, premature aging syndrome with early morbidity due to cardiovascular and cerebrovascular diseases. Clinical symptoms are very diverse, including non-specific symptoms such as growth retardation, scleroderma, alopecia, and osteoporosis, as well as hypertension and cardiovascular diseases that occur in childhood and adolescence due to accelerated vascular aging. In patients with HGPS, MR angiography is recommended for early diagnosis of asymptomatic stroke or vascular changes and to assess increased risk of cerebrovascular disease. We report the second domestic case of HGPS confirmed by genetic analysis in a 5-year-old child with typical clinical features, and the first English case report in Korea to present brain MR angiography findings.

Approaches to the Analysis of Case-Control Studies of the Efficacy of Screening for Cancer

  • Weiss Noel S.;Mcknight Barbara;Stevens Nancy G.
    • 대한예방의학회:학술대회논문집
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    • 1994.02b
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    • pp.188-195
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    • 1994
  • To an increasing extent, case-control studies are being undertaken to determine if use of early detection procedures is associated with reduced mortality from cancer. The authors recommend that in such studies the analysis focus on screening activity in cases that occurs during an interval prior to diagnosis in which the cancer is believed to be detectable and still curable and to a corresponding time period in controls. This approach places a heavy burden on the investigator to estimate accurately the period during which the tumor ought to be detectable using the test in question and to sort out reliably tests done in response to signs or symptoms of the cancer from screening tests per se. Nonetheless, the authors feel that it offers the greatest ability to discern a true benefit of screening, while minimizing the numerous potential biases that can be present in this type of study.

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Community Health Worker Hepatitis B Education for Cambodian American Men and Women

  • Taylor, Victoria Mary;Burke, Nancy Jean;Sos, Channdara;Do, Huyen Hoai;Liu, Qi;Yasui, Yutaka
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.8
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    • pp.4705-4709
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    • 2013
  • Background: Cambodian Americans have high rates of chronic hepatitis B virus (HBV) infection and liver cancer. There is very limited information about the utility of community health worker (CHW) approaches to cancer education for Asian American men. We have previously reported our positive findings from a trial of CHW education about HBV for Cambodian Americans who had never been tested for HBV. This report describes similarities and differences between the outcomes of our CHW HBV educational intervention among Cambodian American men and women. Methods: The study group for this analysis included 87 individuals (39 men and 48 women) who were randomized to the experimental (HBV education) arm of our trial, participated in the CHW educational intervention, and provided follow-up data six months post-intervention. We examined HBV testing rates at follow-up, changes in HBV-related knowledge between baseline and follow-up, and barriers to HBV testing (that were reported to CHWs) by gender. Results: At follow-up, 15% of men and 31% of women reported they had received a HBV test (p=0.09). HBV-related knowledge levels increased significantly among both men and women. With respect to HBV testing barriers, women were more likely than men to cite knowledge deficits, and men were more likely than women to cite logistic issues. Discussion: Our study findings indicate that CHW interventions can positively impact knowledge among Cambodian American men, as well as women. They also suggest CHW interventions may be less effective in promoting the use of preventive procedures by Cambodian American men than women. Future CHW research initiatives should consider contextual factors that may differ by gender and, therefore, potentially influence the relative effectiveness of CHW interventions for men versus women.

The Paradox of the Plankton (플랑크톤 패러독스)

  • Lee, Hak Young;Moon, Sung-Gi;Huh, Man-Kyu
    • Journal of Life Science
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    • v.25 no.5
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    • pp.601-606
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    • 2015
  • Hutchinson (1961) proposed that the large number of species in most plankton communities is remarkable in review of the competitive exclusion principle, which suggests that in homogeneous, well-mixed environments species that compete for the same resources cannot coexist. The principle of competitive exclusion would lead us to conclude that only a few species could coexist in such circumstances. Nevertheless, numerous competing species in most natural habitats are able to coexist, while generally only few resources (niches) limit these communities. It is coined “the paradox of plankton” by Hutchinson. We reviewed some literature of the proposed solutions and give a brief overview of the mechanisms proposed so far. The proposed mechanisms that we discuss mainly include spatial and temporal heterogeneity in physical and biological environment, externally imposed or self-generated spatial segregation, horizontal mesoscale turbulence of ocean characterized by coherent vortices, oscillation and chaos generated by several internal and external causes, stable coexistence and compensatory dynamic under fluctuating temperature in resource competition, and finally the role of toxin-producing phytoplankton in maintaining the coexistence and biodiversity of the overall plankton populations. Especially we sited Roy and Chattopadhyay’s reviews and their toxin-producing hypothesis by phytoplankton. This review may be some information to study plankton communities and effect to put the solutions to the paradox that have been proposed over the years into perspective.

사면안정

  • 이찬구;김남종;윤운상;최원학
    • Proceedings of the KSEG Conference
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    • 2004.03a
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    • pp.22001-22109
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    • 2004
  • 사면 파괴의 분류에 대하여는 여러 학자들(Hutchinson, 1968; Varnes, 1978; Hoek and Bray, 1981)에 의하여 시도되어 왔으며, 일반적으로 파괴면의 기하학적 형상, 물질의 이동 형태와 이동 물질의 종류 등에 따라 분류한다. 현재 널리 사용되는 사면 파괴에 대한 분류로는 Varnes(1978)와 Hoek and Bray(1981)의 분류법이다. 이외 일본 지반 공학회에서는 파괴 두께와 관련된 사면 붕괴 유형을 구분하였다. 여기서는 각각의 분류에 대해 기술하고, 일반적으로 암반 사면에 대한 붕괴 유형 분류를 제시한다. (중략)

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Nonlinear Vibration Characteristics of Piezoelectric Microactuators in Hard Disk Drive Drives (HDD용 압전형 마이크로 액츄에이터의 비선형 진동특성)

  • Chong, Duk-Young;Lee, Seung-Yop;Kim, Chul-Soon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.11a
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    • pp.225-231
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    • 2000
  • Nonlinear characteristics of piezoelectric-type micro actuator used for hard disk drives are experimentally analyzed using Hutchinson's Magnum acturator. The nonlinear effects include hysteresis, superharmonic resonance, jump phenomenon, and shifting of natural frequencies. The effects of exciting frequency and input voltage on the nonlinear phenomena are investigated. It is shown that the micro actuator has the typical 3 times superhamonic resonances coupled to both 1st torsional and sway modes of the suspension.

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A Study on Development of Median Encroachment Accident Model (중앙선침범사고 예측모델의 개발에 관한 연구)

  • 하태준;박제진
    • Journal of Korean Society of Transportation
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    • v.19 no.5
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    • pp.109-117
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    • 2001
  • The median encroachment accident model proposed in this paper is the first step to develop cost-effective criteria about installing facilities preventing traffic accidents by median encroachment. This model consists of expected annual number of median encroachment on roadway and conditional probability to collide with vehicles on opposite lane after encroachment. Expected encroachment number is related to traffic volume and quote from a study of Hutchinson & Kennedy(1966). The probability of vehicle collision is composed of assumed headway distribution of opposite directional vehicles (negative exponential distribution), driving time of encroaching vehicle and Gap & Gap acceptance model. By using expected accident number yielded from the presented model, it will be able to calculate the benefit of reduced accident and to analyze the cost of installing facilities. Therefore this will help develop cost-effective criteria of what, to install in the median.

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Nonlinear Vibrations of Piezoelectric Microactuators in Hard Disk Drives (하드디스크 드라이브용 압전형 마이크로 액추에이터의 비선형 진동 특성)

  • Jeong, Deok-Yeong;Lee, Seung-Yeop;Kim, Cheol-Sun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.25 no.12
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    • pp.2002-2008
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    • 2001
  • Nonlinear vibration characteristics of a piezoelectric-type micro actuator used for hard disk drives are experimentally studied. The nonlinear characterisitics include hysteresis, superharmonic resonance, jump phenomenon, and shifting of natural frequencies. The vibration modes and frequencies of the commercial actuator of the Hutchinson's Magnum series are measured using a laser vibrometer. From harmonic excitation to the PZT acturator, we observe interesting hysteresis patterns with 3 times input frequency. It is shown that the micro actuator has the typical 3 times superhamonic resonances coupled to the first torsional and sway modes of the suspension.