• Title/Summary/Keyword: rare events

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Two Cases of Spontaneous Intracranial Hypotension Treated with Epidural Blood Patch (자발성 두개내 저압환자의 경막외 혈액봉합술 치험 2예)

  • Cho, Soung-Kyung;Joo, Hyun-Chul;Park, Chan-Hong;Kim, Bong-Il;Lee, Sang-Hwa;Oh, Hee-Jong
    • The Korean Journal of Pain
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    • v.12 no.1
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    • pp.152-156
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    • 1999
  • Spontaneous intracranial hypotension (SIH) is a rare syndrome which causes postural headache associated with low cerebrospinal fluid (CSF) pressure, without preceding events such as lumbar puncture, back trauma, operative procedure or illness. The headche is usually accompanied by nausea, vomiting, tinnitus, neck stiffness, vertigo, photophobia and in rare cases diplopia, transient visual obscuration. Brain MRI may show subdural effusion, downward displacement of brain and diffuse and continuous meningeal enhancement when enhanced by gadolinium. Low opening pressure was shown through lumbar puncture. The value of protein and cell count of CSF may be slightly elevated. This syndrome usually resolves itself spontaneously or with strict bed rest. When the headache is persistent or incapacitating, more aggressive treatment may be necessary. We treated two cases of SIH in which epidural blood patch produced immediate and complete relief of the symptoms.

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Classification of Weather Patterns in the East Asia Region using the K-means Clustering Analysis (K-평균 군집분석을 이용한 동아시아 지역 날씨유형 분류)

  • Cho, Young-Jun;Lee, Hyeon-Cheol;Lim, Byunghwan;Kim, Seung-Bum
    • Atmosphere
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    • v.29 no.4
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    • pp.451-461
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    • 2019
  • Medium-range forecast is highly dependent on ensemble forecast data. However, operational weather forecasters have not enough time to digest all of detailed features revealed in ensemble forecast data. To utilize the ensemble data effectively in medium-range forecasting, representative weather patterns in East Asia in this study are defined. The k-means clustering analysis is applied for the objectivity of weather patterns. Input data used daily Mean Sea Level Pressure (MSLP) anomaly of the ECMWF ReAnalysis-Interim (ERA-Interim) during 1981~2010 (30 years) provided by the European Centre for Medium-Range Weather Forecasts (ECMWF). Using the Explained Variance (EV), the optimal study area is defined by 20~60°N, 100~150°E. The number of clusters defined by Explained Cluster Variance (ECV) is thirty (k = 30). 30 representative weather patterns with their frequencies are summarized. Weather pattern #1 occurred all seasons, but it was about 56% in summer (June~September). The relatively rare occurrence of weather pattern (#30) occurred mainly in winter. Additionally, we investigate the relationship between weather patterns and extreme weather events such as heat wave, cold wave, and heavy rainfall as well as snowfall. The weather patterns associated with heavy rainfall exceeding 110 mm day-1 were #1, #4, and #9 with days (%) of more than 10%. Heavy snowfall events exceeding 24 cm day-1 mainly occurred in weather pattern #28 (4%) and #29 (6%). High and low temperature events (> 34℃ and < -14℃) were associated with weather pattern #1~4 (14~18%) and #28~29 (27~29%), respectively. These results suggest that the classification of various weather patterns will be used as a reference for grouping all ensemble forecast data, which will be useful for the scenario-based medium-range ensemble forecast in the future.

Simulations of Thermal Stratification of Daecheong Reservoir using Three-dimensional ELCOM Model (3차원 ELCOM 모형을 이용한 대청호 수온성층 모의)

  • Chung, Se Woong;Lee, Heung Soo;Choi, Jung Kyu;Ryu, In Gu
    • Journal of Korean Society on Water Environment
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    • v.25 no.6
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    • pp.922-934
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    • 2009
  • The transport of contaminants and spatial variation in a deep reservoir are certainly governed by the thermal structure of the reservoir. There has been continuous efforts to utilize three-dimensional (3D) hydrodynamic and water quality models for supporting reservoir management, but the efforts to validate the models performance using extensive field data were rare. The study was aimed to evaluate a 3D hydrodynamic model, ELCOM, in Daecheong Reservoir for simulating heat fluxes and stratification processes under hydrological years of 2001, 2006, 2008, and to assess the impact of internal wave on the reservoir mixing. The model showed satisfactory performance in simulating the water temperature profiles: the absolute mean errors at R3 (Hoenam) and R4 (Dam) sites were in the range of $1.38{\sim}1.682^{\circ}C$. The evaporative and sensible heat losses through the reservoir surface were maximum during August and January, respectively. The net heat flux ($H_n$) was positive from February to September, while the stratification formed from May and continued until September. Instant vertical mixing was observed in the reservoir during strong wind events at R4, and the model reasonably reproduced the mixing events. A digital low-pass filter and zero crossing method was used to evaluate the potential impact of wind-driven internal wave on the reservoir mixing. The results indicated that most of the wind events occurred in 2001, 2006, 2008 were not enough to develop persistent internal wave and effective mixing in the reservoir. ELCOM is a suitable 3D model for supporting water quality management of the deep and stratified reservoirs.

Review of Studies on Fire Needle (화침에 대한 국내외 연구 경향 고찰)

  • Moon, Su-Jeong;Kong, Jae-Cheol;Jo, Dong-Chan;Kim, Esther;Song, Young-Sun;Lee, Jung-Han
    • Journal of Korean Medicine Rehabilitation
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    • v.21 no.4
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    • pp.67-76
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    • 2011
  • Objectives: The aim of this review was to investigate studies on fire needle and to propose for the better method of studies in the future. Methods: Studies related to fire needle were searched with electric database for this study, and 10 domestic and overseas databases were included. Results: 19 clinical studies were analyzed in terms of condition, time of heating, number and frequency of treatment, number of heating, safety procedure or device aid reports of adverse events. Also 3 review studies were summarized. The number of studies was increasing and the kind of diseases to treat with fire noodle were various. Especially musculoskeletal diseases like ligament lesion and lumbago were noticeable. Heating-after-insertion method was recently proposed but the use of term was confusing. The report of adverse events or safety procedure was rare. Also there was an effort to develop more convenient and safer device. Conclusions: High quality clinical trial en fire needle is needed especially to compare 2 methods, heating-after-insertion and heating-before-insertion. And studies need to report safety procedures and adverse events to evaluate the safety of fire needle therapy.

Cerebrovascular Events in Pediatric Inflammatory Bowel Disease: A Review of Published Cases

  • Rohani, Pejman;Taraghikhah, Nazanin;Nasehi, Mohammad Mehdi;Alimadadi, Hosein;Aghdaei, Hamid Assadzadeh
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.25 no.3
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    • pp.180-193
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    • 2022
  • Pediatric inflammatory bowel disease (PIBD) is a multisystem disorder characterized by intestinal and extraintestinal manifestations and complications. Cerebrovascular events (CVE) are rare extraintestinal complications in patients with PIBD. Statistics show that 3.3% patients with PIBD and 1.3-6.4% adult patients with inflammatory bowel disease (IBD) experience CVE during the course of the disease. Therefore, this study aimed to review the records of children with IBD who developed CVE during the course of the disease. We retrospectively reviewed 62 cases of PIBD complicated by CVE. The mean patient age at the time of thrombotic events was 12.48±4.13 years. The incidence of ulcerative colitis was significantly higher than that of Crohn's disease (43 [70.5%] vs. 13 [21.3%] patients). Most patients (87.93%) were in the active phase of IBD at the time of CVE. The mean time interval between the onset of IBD and CVE was 20.84 weeks. Overall, 11 (26.83%) patients showed neurological symptoms of CVE at disease onset. The most frequent symptom on admission was persistent and severe headaches (67.85%). The most common site of cerebral venous thrombosis was the transverse sinuses (n=23, 53.48%). The right middle cerebral artery (n=3, 33.34%) was the predominant site of cerebral arterial infarction. Overall, 41 (69.49%) patients who were mostly administered unfractionated heparin or low-molecular-weight heparin (56.09%) recovered completely. Patients with IBD are at a risk of thromboembolism. CVE may be the most common type of thromboembolism. Based on these findings, the most common risk factor for CVE is IBD flares. In patients with CVE, anticoagulant therapy with heparin, followed by warfarin, is necessary.

Feasibility Study on the Fault Tree Analysis Approach for the Management of the Faults in Running PCR Analysis (PCR 과정의 오류 관리를 위한 Fault Tree Analysis 적용에 관한 시범적 연구)

  • Lim, Ji-Su;Park, Ae-Ri;Lee, Seung-Ju;Hong, Kwang-Won
    • Applied Biological Chemistry
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    • v.50 no.4
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    • pp.245-252
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    • 2007
  • FTA (fault tree analysis), an analytical method for system failure management, was employed in the management of faults in running PCR analysis. PCR is executed through several processes, in which the process of PCR machine operation was selected for the analysis by FTA. The reason for choosing the simplest process in the PCR analysis was to adopt it as a first trial to test a feasibility of the FTA approach. First, fault events-top event, intermediate event, basic events-were identified by survey on expert knowledge of PCR. Then those events were correlated deductively to build a fault tree in hierarchical structure. The fault tree was evaluated qualitatively and quantitatively, yielding minimal cut sets, structural importance, common cause vulnerability, simulation of probability of occurrence of top event, cut set importance, item importance and sensitivity. The top event was 'errors in the step of PCR machine operation in running PCR analysis'. The major intermediate events were 'failures in instrument' and 'errors in actions in experiment'. The basic events were four events, one event and one event based on human errors, instrument failure and energy source failure, respectively. Those events were combined with Boolean logic gates-AND or OR, constructing a fault tree. In the qualitative evaluation of the tree, the basic events-'errors in preparing the reaction mixture', 'errors in setting temperature and time of PCR machine', 'failure of electrical power during running PCR machine', 'errors in selecting adequate PCR machine'-proved the most critical in the occurrence of the fault of the top event. In the quantitative evaluation, the list of the critical events were not the same as that from the qualitative evaluation. It was because the probability value of PCR machine failure, not on the list above though, increased with used time, and the probability of the events of electricity failure and defective of PCR machine were given zero due to rare likelihood of the events in general. It was concluded that this feasibility study is worth being a means to introduce the novel technique, FTA, to the management of faults in running PCR analysis.

Spontaneous Intracranial Hypotension Treated with Epidural Blood Patch -A case report- (경막외 혈액봉합술로 치험한 자발성 두개내 저압 -증례 보고-)

  • Moon, Dong-Eon;Kim, Byung-Chan;Kim, Young-Ju;Lee, Kwang-Soo
    • The Korean Journal of Pain
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    • v.10 no.1
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    • pp.109-112
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    • 1997
  • Spontaneous intracranial hypotension(SIH) is a rare syndrome of spontaneously occurring postural headache associated with low CSF pressure. It usually occur without evidence of any preceeding events such as lumbar puncture, back trauma, operative procedure, or medical illness. This syndrome usually resolves spontaneously or with strict bed rest. When the headache persists or is incapacitating, more aggressive treatment may be necessary. Autologous epidural blood patch is highly effective in the management of SIH. We experienced a case of SIH with downward displacement of brain in MRI and successfully treated with epidural blood patch.

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Malformations of cortical development: genetic mechanisms and diagnostic approach

  • Lee, Jeehun
    • Clinical and Experimental Pediatrics
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    • v.60 no.1
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    • pp.1-9
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    • 2017
  • Malformations of cortical development are rare congenital anomalies of the cerebral cortex, wherein patients present with intractable epilepsy and various degrees of developmental delay. Cases show a spectrum of anomalous cortical formations with diverse anatomic and morphological abnormalities, a variety of genetic causes, and different clinical presentations. Brain magnetic resonance imaging has been of great help in determining the exact morphologies of cortical malformations. The hypothetical mechanisms of malformation include interruptions during the formation of cerebral cortex in the form of viral infection, genetic causes, and vascular events. Recent remarkable developments in genetic analysis methods have improved our understanding of these pathological mechanisms. The present review will discuss normal cortical development, the current proposed malformation classifications, and the diagnostic approach for malformations of cortical development.

Extreme wind prediction and zoning

  • Holmes, J.D.;Kasperski, M.;Miller, C.A.;Zuranski, J.A.;Choi, E.C.C.
    • Wind and Structures
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    • v.8 no.4
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    • pp.269-281
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    • 2005
  • The paper describes the work of the IAWE Working Group WGF - Extreme Wind Prediction and Zoning, one of the international codification working groups set up in 2000. The topics covered are: the international database of extreme winds, quality assurance and data quality, averaging times, return periods, probability distributions and fitting methods, mixed wind climates, directionality effects, the influence of orography, rare events and simulation methods, long-term climate change, and zoning and mapping. Recommendations are given to promote the future alignment of international codes and standards for wind loading.

A novel association between cerebral sinovenous thrombosis and nonketotic hyperglycinemia in a neonate

  • Yurttutan, Sadik;Oncel, Mehmet Yekta;Yurttutan, Nursel;Degirmencioglu, Halil;Uras, Nurdan;Dilmen, Ugur
    • Clinical and Experimental Pediatrics
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    • v.58 no.6
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    • pp.230-233
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    • 2015
  • Lethargy in newborns usually indicates central nervous system dysfunction, and many conditions such as cerebrovascular events, infections, and metabolic diseases should be considered in the differential diagnosis. Nonketotic hyperglycinemia is an autosomal recessive error of glycine metabolism, characterized by myoclonic jerks, hypotonia, hiccups, apnea, and progressive lethargy that may progress to encephalopathy or even death. Cerebral sinovenous thrombosis is a rare condition with various clinical presentations such as seizures, cerebral edema, lethargy, and encephalopathy. Here, we report the case of a newborn infant who presented with progressive lethargy. An initial diagnosis of cerebral venous sinus thrombosis was followed by confirmation of the presence of nonketotic hyperglycinemia.