• Clinical and Experimental Pediatrics
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• 제60권7호
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• pp.221-226
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• 2017

Purpose: Escherichia coli sequence type (ST) 131, a multidrug-resistant clone causing extraintestinal infections, has rapidly become prevalent worldwide. However, the epidemiological and clinical features of pediatric infections are poorly understood. We aimed to explore the characteristics of ST131 Escherichia coli isolated from Korean children with urinary tract infections. Methods: We examined 114 uropathogenic E. coli (UPEC) isolates from children hospitalized at Chung-Ang University Hospital between 2011 and 2014. Bacterial strains were classified into STs by partial sequencing of seven housekeeping genes (adk, fumC, gyrB, icd, mdh, purA, and recA). Clinical characteristics and antimicrobial susceptibility were compared between ST131 and non-ST131 UPEC isolates. Results: Sixteen UPEC isolates (14.0%) were extended-spectrum ${\beta}-lactamase$ (ESBL)-producers; 50.0% of ESBL-producers were ST131 isolates. Of all the isolates tested, 13.2% (15 of 114) were classified as ST131. There were no statistically significant associations between ST131 and age, sex, or clinical characteristics, including fever, white blood cell counts in urine and serum, C-reactive protein, radiologic abnormalities, and clinical outcome. However, ST131 isolates showed significantly lower rates of susceptibility to cefazolin (26.7%), cefotaxime (40.0%), cefepime (40.0%), and ciprofloxacin (53.3%) than non-ST131 isolates (65.7%, 91.9%, 92.9%, and 87.9%, respectively; P<0.001 for all). ESBL was more frequently produced in ST131 (53.3%) than in non-ST131 (8.1%) isolates (P<0.01). Conclusion: ST131 E. coli isolates were prevalent uropathogens in children at a single medical center in Korea between 2011 and 2014. Although ST131 isolates showed higher rates of antimicrobial resistance, clinical presentation and outcomes of patients were similar to those of patients infected with non-ST131 isolates.

• 한국건축시공학회지
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• 제10권3호
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• pp.113-120
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• 2010

본 연구에서는 실내 배합 실험을 통하여 150MPa 초고강도 콘크리트의 제반 물성을 평가한 후 150MPa 초고강도 콘크리트제조를 위한 최적 배합 조건을 제시하고자 하며 압축강도, 응력-변형률 관계, 탄성계수와 인장강도, 휨강도 등과 같은 기본적인 재료역학 특성을 평가하고자 한다. 이를 위하여 초고강도 콘크리트의 목표 물성으로 배합강도는 150MPa, 슬럼프 플로는 $700{\pm}50mm$를 목표로 정하여 57개의 배합을 실시하였으며, 각각의 배합조건에 따른 물성 및 역학특성을 검토하였다. 실험결과 초고강도 콘크리트는 보통의 고강도 콘크리트보다 매우 큰 점성을 가지므로 이러한 점성과 콘크리트 타설 및 작업성의 상관성을 고려하여 700~800mm 정도의 플로값을 확보하여야 할 것으로 판단되며, 재령 56일 압축강도를 100%로 할 때 3일은 64%, 7일은 70%, 28일은 약 95% 발현하였다. 150MPa 정도의 초고강도 콘크리트 제조를 위한 단위 시멘트량은 대략 1030~1150kg/$m^3$ 정도이며, 물-결합재비는 12~14%의 범위 내에서 적당하며, 잔골재율은 점성 및 작업성을 고려하여 30~35% 범위 내에서 결정될 수 있음을 확인하였다.

• Clinical and Experimental Pediatrics
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• 제54권6호
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• pp.234-240
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• 2011

Acute disseminated encephalomyelitis (ADEM) is a demyelinating disease of the central nervous system (CNS) that typically presents as a monophasic disorder associated with multifocal neurologic symptoms and encephalopathy. ADEM is considered an autoimmune disorder that is triggered by an environmental stimulus in genetically susceptible individuals. The diagnosis of ADEM is based on clinical and radiological features. Most children with ADEM initially present with fever, meningeal signs, and acute encephalopathy. The level of consciousness ranges from lethargy to frank coma. Deep and subcortical white-matter lesions and gray-matter lesions such as thalami and basal ganglia on magnetic resonance imaging (MRI) are associated with ADEM. In a child who presents with signs of encephalitis, bacterial and viral meningitis or encephalitis must be ruled out. Sequential MRI is required to confirm the diagnosis of ADEM, as relapses with the appearance of new lesions on MRI may suggest either multiphasic ADEM or multiple sclerosis (MS). Pediatric MS, defined as onset of MS before the age of 16, is being increasingly recognized. MS is characterized by recurrent episodes of demyelination in the CNS separated in space and time. The McDonald criteria for diagnosis of MS include evidence from MRI and allow the clinician to make a diagnosis of clinically definite MS on the basis of the interval preceding the development of new white matter lesions, even in the absence of new clinical findings. The most important alternative diagnosis to MS is ADEM. At the initial presentation, the 2 disorders cannot be distinguished with certainty. Therefore, prolonged follow-up is needed to establish a diagnosis.

• Clinical and Experimental Pediatrics
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• 제60권4호
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• pp.106-111
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• 2017

Purpose: This study aimed to determine the prevalence of glucose-6-phosphate dehydrogenase (G6PD) deficiency among infants with neonatal indirect hyperbilirubinemia (NIH); compare G6PD-deficient and G6PD-normal patients regarding hyperbilirubinemia and need for exchange transfusions (ET); and assess risk factors for ET and kernicterus. Methods: This is a case-control retrospective study. Medical records of NIH patients admitted to the Pediatric Department, Salmaniya Medical Complex, Bahrain, between January 2007 and June 2010 were reviewed. Data on sex, age at presentation, hospitalization duration, need for ET, hemoglobin (Hb) level, reticulocyte count, direct Coombs test, serum total and indirect bilirubin levels, thyroid function, blood and urine cultures, G6PD status, and blood groups were collected and compared between the G6PD-deficent and G6PD-normal patients. Results: Of 1,159 NIH patients admitted, 1,129 were included, of whom 646 (57%) were male. Among 1,046 patients tested, 442 (42%) were G6PD deficient, 49 (4%) needed ET, and 11 (1%) had suspected Kernicterus. The G6PD-deficient patients were mainly male (P<0.0001), and had lower Hb levels (P<0.0001) and higher maximum bilirubin levels (P=0.001). More G6PD-deficient patients needed ET (P<0.0001). G6PD deficiency (P=0.006), lower Hb level (P=0.002), lower hematocrit count (P=0.02), higher bilirubin level (P<0.0001), higher maximal bilirubin level (P<0.0001), and positive blood culture result (P<0.0001) were significant risk factors for ET. Maximal bilirubin level was a significant risk factor for kernicterus (P=0.021) and independently related to ET (P=0.03). Conclusion: G6PD deficiency is an important risk factor for severe NIH. In G6PD-deficent neonates, management of NIH should be hastened to avoid irreversible neurological complications.

• 공업화학
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• 제21권5호
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• pp.559-563
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• 2010

천연색소를 이용한 컬러의 재현은 현대의 웰빙 생활과 밀접한 연관성을 갖게 된다. 이 연구는 일상생활에서 자주 쓰이는 녹색 계, 황색 계, 그리고 적색 계의 컬러를 자연 상의 녹차, 치자, 흑미를 색소원으로 하여 목표 색을 설정하였다. 목표색의 명도(L), 색 좌표(a, b)의 정량적 수치 값을 지정하고 추출용매의 물성을 조절함으로써 목표 색에 가장 접근하는 색을 추출하여 표현하였다. 색소추출 공정에서 용매의 pH, 추출온도, 추출시간이 변수로 설정되었다. 치자의 경우 추출시간이 길수록 진한색이 추출되었다. 추출색소는 색차계를 이용해 색의 L-a-b좌표를 측정하여 목표 색과 비교하였다. 실험조건을 최적화함으로써 목표 색과 가장 색차 값(${\Delta}E$)이 적은 녹색, 황색, 적색의 CIE 기준 값을 제시하고 이 좌표에 맞는 색을 표현하였다.

• 한국과학교육학회지
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• 제33권7호
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• pp.1259-1272
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• 2013

본 연구는 탐구적 과학 글쓰기 실험수업이 중학생들의 창의적 사고와 비판적 사고에 미치는 효과를 알아보기 위한 것으로 이를 위해 Keys 등(1999)이 개발한 SWH 전략에 기초하여 탐구적 과학 글쓰기 프로그램을 개발하였다. 연구의 대상은 2개 학급 63명은 비교집단으로, 2개 학급은 실험집단으로 선정하였고, 소집단의 구성은 인지수준이 비슷한 동질집단으로 구성하였다. 프로그램의 처치는 2011년 3월부터 7월까지 9개의 활동 주제로 총 18차시를 투입하였다. 사후검사는 사전검사와 동일한 검사지를 사용하였으며, 검사 결과는 SPSS 20.0 프로그램을 사용하여 창의적 사고와 비판적 사고의 사전검사를 공변인으로 하는 공변량 분석(ANCOVA)으로 통계 처리하였다. 또한 설문지를 이용하여 학생들의 탐구적 과학 글쓰기 실험수업에 대한 인식을 알아보았다. 이러한 연구결과를 살펴보면, 탐구적 과학 글쓰기 실험수업이 창의적 문제해결력 향상에 효과적이므로, 지속적인 탐구적 과학 글쓰기 수업전략의 제시와 다양한 실험 주제 개발이 필요하다고 여겨진다.

• International Journal of Fluid Machinery and Systems
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• 제8권4호
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• pp.264-273
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• 2015

This presentation describes an experimental approach for the detection of cavitation in hydraulic machines by use of ultrasonic signal analysis. Instead of using the high frequency pulses (typically 1MHz) only for transit time measurement different other signal characteristics are extracted from the individual signals and its correlation function with reference signals in order to gain knowledge of the water conditions. As the pulse repetition rate is high (typically 100Hz), statistical parameters can be extracted of the signals. The idea is to find patterns in the parameters by a classifier that can distinguish between the different water states. This classification scheme has been applied to different cavitation sections: a sphere in a water flow in circular tube at the HSLU in Lucerne, a NACA profile in a cavitation tunnel and two Francis model test turbines all at LMH in Lausanne. From the signal raw data several statistical parameters in the time and frequency domain as well as from the correlation function with reference signals have been determined. As classifiers two methods were used: neural feed forward networks and decision trees. For both classification methods realizations with lowest complexity as possible are of special interest. It is shown that two to three signal characteristics, two from the signal itself and one from the correlation function are in many cases sufficient for the detection capability. The final goal is to combine these results with operating point, vibration, acoustic emission and dynamic pressure information such that a distinction between dangerous and not dangerous cavitation is possible.

• Clinical and Experimental Pediatrics
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• 제61권5호
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• pp.160-166
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• 2018

Purpose: This study aimed to analyse laboratory values according to fever duration, and evaluate the relationship across these values during the acute phase of Kawasaki disease (KD) to aid in the early diagnosis for early-presenting KD and incomplete KD patients. Methods: Clinical and laboratory data of patients with KD (n=615) were evaluated according to duration of fever at presentation, and were compared between patients with and without coronary artery lesions (CALs). For evaluation of the relationships across laboratory indices, patients with a fever duration of 5 days or 6 days were used (n=204). Results: The mean fever duration was $6.6{\pm}2.3days$, and the proportions of patients with CALs was 19.3% (n=114). C-reactive proteins (CRPs) and neutrophil differential values were highest and hemoglobin, albumin, and lymphocyte differential values were lowest in the 6-day group. Patients with CALs had longer total fever duration, higher CRP and neutrophil differential values and lower hemoglobin and albumin values compared to patients without CALs. CRP, albumin, neutrophil differential, and hemoglobin values at the peak inflammation stage of KD showed positive or negative correlations each other. Conclusion: The severity of systemic inflammation in KD was reflected in the laboratory values including CRP, neutrophil differential, albumin, and hemoglobin. Observing changes in these laboratory parameters by repeated examinations prior to the peak of inflammation in acute KD may aid in diagnosis of early-presenting KD patients.

• 정보관리학회지
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• 제1권1호
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• pp.112-126
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• 1984

정보가 폭증함에 따라 이용자로 하여금 필요한 정보에 접근할 수 있게 해주는 서지정보검색도구의 생산이 날로 증가되고 있다. 이용자를 위한 보다 효율적인 서지정보검색도그를 생산해낼 수 있는 개선방안을 모색해 보기 위하여 우리나라에서 주로 이용되는 7종의 서지도구의 이용상황 및 그 특성에 대한 이용자의 선호도를 조사한 결과 한 두 종류의 서지도구가 집중적으로 이용되고 있으며 이용도가 높은 서지도구일수록 불만족의 응답율이 높게 나타났다. 또 가장 많이 이용되는 4종의 서지도구의 인쇄형태가 검색효율에 미치는 영향을 조사해보기 위해 실험검색을 실시한 결과 4종의 서지도구가 공통적으로 낮은 검색율을 나타내었고 그중 정기간행물기사색인의 경우 가장 낮은 검색율을 보이고 있다. 이상의 조사 결과를 종합해 볼 때 우리나라에서 발간되는 서지자료들이 보다 사용하기 쉽고 편리한 정보검색도구로써 그 역할을 다 할 수 있으려면 광범한 이용조사를 통해 이용자의 요구를 정확히 반영할 수 있는 개선책이 시급히 요구되고 있다.

• 한국초등과학교육학회지:초등과학교육
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• 제39권3호
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• pp.449-463
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• 2020

This study was to analysis teaching strategies, types of inquiry activities and the relationship between science concepts and inquiry activities presented in science textbooks. As a result of the study, first, the inquiry-based teaching strategies presented in science textbooks were experiment, simulation, demonstration, and field study. Second, there were 53 inquiry activities presented in 8 units related to the earth science area of science textbooks, and the types of inquiry activities were experimental observation (EO) 18, mock activity (SA) 20, investigation discussion and presentation (IP). It was analyzed as 12, data interpretation (ID) 2, and express (EX) 1 piece. Third, the relationship between inquiry activities and science concepts presented in science textbooks was analyzed. As a result of the analysis, out of a total of 42 inquiry activities, 21 inquiry activities corresponded to EA (explicit activities), in which the result of inquiry activities was directly and explicitly linked to science concepts. And IA (implicit activities), which is an implicit inquiry activity in which science concepts must be inferred using the results of inquiry activities, were analyzed as 21. In particular, IA (implicit activities), which is an implicit inquiry activity, can be said to be the result of reflecting the characteristics of earth science areas where many simulated activities (SA) are used. This is considered to be a matter to be considered in the process of developing various elementary science textbooks in the future.