• The Mathematical Education
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• v.54 no.3
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• pp.223-240
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• 2015

This study qualitatively investigates the nature of the challenges that a student who is highly successful in mathematics faces in learning college-level elementary statistics. The study draws on the constructs of eagerness, flexibility and willingness to characterize the necessary disposition for critical thinking that is essential in learning statistics. The case study is based on data collected through a survey assessment and a follow-up interview with a mathematics major enrolled in an elementary college statistics course at the time of the study. The qualitative analysis relies on the student's verbal descriptions of the challenges he was experiencing in the course. The findings suggest that while his strong inclination towards inquisitive learning and strong understanding of mathematical concepts supported this student's mathematics learning, the same characteristics might have been causing him difficulties in learning college-level elementary statistics.

• Journal of Life Science
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• v.9 no.4
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• pp.358-367
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• 1999

Thirty strains of methicillin resistant Staphylococcus aureus were obtained from the clinical isolates. In order to investigate the pursuit of the pathogens of nosocomial infection, these strains were studied for antibiotic sensitivity as well as its resistant pattern. Among the methods of hybridization which directly confirm the specific antibiotic resistant genes by means of the recently developed specific probe DNA, dot blot hybridization and southern blot hybridization were performed and these two methods were compared in their sensitivity and specificity. Strains that is sensitive to cephalothin to the subject of methicillin resistant Staphylococcus aureus were in 43%. Those that are sensitive to cefoperazone and cefuroxime were 26% and 23%, respectively. In case of MIC, MIC50 of cefoperazone was 8 $\mu\textrm{g}$/$m\ell$, and MIC90 was 128 $\mu\textrm{g}$/$m\ell$ to be the lowest. As the results of plasmid DNA electrophoresis, most of methicillin resistant Staphylococcus aureus strains had more than 4 plasmids. These plasmids digested by BamHI, methicillin resistant Staphylococcus aureus is distributed as 10 fragments with the size of 65 kb to 1.5 kb. Dot blot hybridization were performed to examine the existence of mecA gene to show the detection rate of 50%. Southern blot hybridization were done to see if DNA bands which amplify the activity of digoxigenium-labeled probe by PCR were actually PCR products of mecA gene and it showed the detection rate of 53%. It can be concluded that the southern blot hybridization seemed to be better in sensitivity and specificity when it is compared with the results of dot blot hybridization.

• Korean Journal of Community Nutrition
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• v.14 no.3
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• pp.340-353
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• 2009

It is very important to screen the elderly for nutritional risk, because nutritional status is a critical factor to maintain their health. Some nutrition checklists used in Korea for the elderly are from other countries. Reliability of those checklist in Korea is not studied enough. This survey was done for the elderly over 65-years-old who live in Hong-cheon, An-dong, Dam-yang and Yeon-gi in Korea (subject; summer: 146, winter: 145) to study the reliability of DETERMINE checklist which is adopted widely in Korea. Using the score of DETERMINE checklist, the elderly were divided as high, middle and low risk groups. For nutritional assessment for those elderly, dietary assessment using 24 recall, anthropometry, biochemical assessment and health condition were used. Results for the checklist showed that percentage below EAR for energy intake and protein intake in winter were higher in the high risk group than other groups. The intakes of phosphorus and iron and most vitamins were below the DRI. The percentage of subjects with intake below DRI was highest in the high risk group. Sensitivity, specificity, and positive predictive values using the DETERMINE were calculated using 6 point as a cut-off point. Subjects were divided into two groups by MAR (MAR < 0.75:undernutrition, MAR < 0.75 : normal). Sensitivity recorded 49.4% and 34.3%, specificity did 61.9% and 65.4 and Positive predictive value did 62.1% and 46.0% each for summer and winter. Results of screening using DETERMINE Checklist were not matched with dietary assessment but not with anthropometric and biochemical measurement. In conclusion DETERMINE 'Checklist' is shown be a good screening tool for finding out risk groups for dietary intake in the elderly, It needs to verify reliability and validity through large-scale survey.

• The Plant Pathology Journal
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• v.16 no.1
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• pp.1-8
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• 2000

Worldwide, rice blast, caused by Magnaporthe grisea (Hebert) Barr. (anamorph, Pyricularia grisea Sacc.), is one of the most economically devastating crop diseases. Management of rice blast through the breeding of blast-resistant varieties has had only limited xuccess due to the frequent breakdown of resistance under field conditions (Bonman etal., 1992; Correa-Victoria and Zeigler, 1991; Kiyosawa, 1982). The frequent variation of race in pathogen populations has been proposed as the principal mechanism involved in the loss of resistance (Ou, 1980). Although it is generally accepted that race change in M. grisea occurs in nature, the degree of its variability has been a controversial subject. A number of studies have reported the appearance of new races at extremely high rates (Giatgong and Frederiksen, 1968; Ou and Ayad, 1968; Ou et al., 1970; Ou et al., 1971). Various potential mechanisms, including heterokaryosis (Suzuki, 1965), parasexual recombination (Genovesi and Magill, 1976), and aneuploidy (Kameswar Row et al., 1985; Ou, 1980), have been proposed to explain frequent race changes. In contrast, other studies have shown that although race change could occur, its frequency was much lower than that predicted by earlier studies (Bonman et al., 1987; Latterell and Rossi, 1986; Marchetti et al., 1976). Although questions about the frequency of race changes in M. grisea remain unanswered, the application of molecular genetic tools to study the fungus, ranging from its genes controlling host specificity to its population sturctures and dynamics, have begun to provide new insights into the potential mechanisms underlying race variation. In this review we aim to provide an overview on (a) the molecular basis of host specificity of M. grisea, (b) the population structure and dynamics of rice pathogens, and (c) the nature and mechanisms of genetic changes underpinning virulence variation in M. grisea.

• Korean Journal of Plant Resources
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• v.34 no.1
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• pp.52-58
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• 2021

Homogenization of quality was important in order to use herbal medicines as pharmaceuticals. To solve this problem, it was important to establish quality standards. Atractylodis Rhizoma Alba has no quantitative method in the Korean Pharmacopoeia. Thus, we have researched to improve the quality evaluation method of Atractylodis Rhizoma Alba with an HPLC. Atractylenolide III and atracylodin were selected as potential marker compounds. This analytical procedure was subject to validation. According to validation guideline of South Korea's Ministry of Food and Drugs Safety, the specificity, linearity, precision, range, quantitative limits, detection limits and accuracy were measured. Because the specificity, linearity, precision, range, quantitative limits, detection limits and accuracy meet criteria of the guideline, the analytic method was validated. With this analysis, Atractylodis Rhizoma Alba and Atractylodis Rhizoma analyzed. As a result, both atractylenolide III and atracylodin appear to be suitable standard compounds. it confirmed that tractylodes Rhizome, similar to Atractylodes Rhizome Alba, could be distinguished.

• The Korean Journal of Cytopathology
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• v.18 no.2
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• pp.119-125
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• 2007

Urine cytology is an important screening tool for urinary tract neoplasms. Liquid-based preparation methods, such as $ThinPrep^{(R)}$, have been introduced for non-gynecological samples. We aimed to assess the diagnostic accuracy of liquid-based preparations in urine cytology by comparing the results of the conventional Cytospin preparation method for the same samples. A total of 236 cases subject to urine cytology were enrolled in this study from January 2005 to December 2005. All cases were subjected to cystoscopy and if a malignancy was suspected, a biopsy was performed. Urine cytology slides were made using the $ThinPrep^{(R)}$ preparation method and the conventional Cytospin and/or direct smear method from the individual samples. The results of urine cytology were compared with the final cystoscopic or histological diagnoses. We analyzed the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of both cytology preparation methods. A total of 236 slides made using the liquid based method were satisfactory for slide quality, whereas 5 slides (2.1%) prepared by conventional methods were unsatisfactory because of air-drying, a thick smear, or a bloody or inflammatory background. The $ThinPrep^{(R)}$ method showed 53.1% sensitivity, 92.6% specificity, a 92,6% positive predictive value, a 94.1% negative predictive value and 85,6% accuracy, while the conventional method showed 51% sensitivity, 98.4% specificity, a 92.6% positive predictive value, a 98.4% negative predictive value and 88,6% accuracy. Although the diagnostic values were equivalent between the use of the two methods, the quality of the cytology slides and the time consumed during the microscopic examination for a diagnosis were superior for the $ThinPrep^{(R)}$ method than for the conventional method. In conclusion, our limited studies have shown that the use of the liquid based preparation method is beneficial to improve the quality of slides and reduce the duration for a microscopic examination, but did not show better sensitivity, accuracy and predictive values.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.7 no.2
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• pp.19-26
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• 2013

This paper propose a surface EMG signal based gait phase recognition method that selects features and channels adaptively. The proposed method can be used to control powered artificial prosthetic for lower limb amputees and can reduce overhead in real-time pattern recognition by selecting adaptive channels and features in an embedded device. The method can enhance the classification accuracy by adaptively selecting channels and features based on sensitivity and specificity of each subject because EMG signal patterns may vary according to subject's locomotion convention. In the experiments, we found that the muscles with highest recognition rate are different between human subjects. The results also show that the average accuracy of the proposed method is about 91% whereas those of existing methods using all channels and/or features is about 50%. Therefore we assure that sEMG signal based gait phase recognition using small number of adaptive muscles and corresponding features can be applied to control powered artificial prosthetic for lower limb amputees.

• Clinical and Experimental Pediatrics
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• v.59 no.10
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• pp.402-407
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• 2016

Purpose: Buckwheat allergy is one of the most severe types of food allergy in some countries, especially among children. However, few studies have investigated this condition. The aim of this study was to report the clinical and laboratory findings in Korean children with buckwheat allergy. Methods: Thirty-seven subjects, aged 1 to 14 years, were enrolled by retrospective medical record review from January 2000 through May 2015 at the Department of Pediatrics in Ajou University Hospital. The demographic profile, previous exposure to buckwheat pillows, clinical symptoms, and laboratory findings of each subject were recorded. Results: Twenty-six of the 37 children had immediate-type allergic symptoms to buckwheat, while 11 subjects were tolerant to buckwheat. Seventeen out of 26 buckwheat allergic children (65.4%) had anaphylaxis. The median buckwheat specific IgE level in the buckwheat allergic group ($7.71kU_A/L$) was significantly higher (P<0.001) than in the buckwheat tolerant group ($0.08kU_A/L$) with an optimal cutoff value of $1.27kU_A/L$ (sensitivity 84.6%, specificity 100%). When adjusted for age, the difference between the 2 groups showed no statistical significance (P=0.063). In subjects who had anaphylaxis, buckwheat-specific IgE levels ranged from 0.37 to $100kU_A/L$. Conclusion: Almost two-thirds of buckwheat-allergic children had anaphylaxis, and a wide-range of buckwheat specific IgE levels were observed in these children. Anaphylaxis occurred in a subject with a remarkably low IgE level ($0.37kU_A/L$).

• Journal of Korean Academy of Nursing
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• v.35 no.1
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• pp.47-55
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• 2005

Purpose: This study was to evaluate the validity of the Pediatric Index of Mortality Ⅱ(PIM Ⅱ). Method: The first values on PIM Ⅱ variables following ICU admission were collected from the patient's charts of 548 admissions retrospectively in three ICUs(medical, surgical, and neurosurgical) at P University Hospital and a cardiac ICU at D University Hospital in Busan from January 1, 2002 to December 31, 2003. Data was analyzed with the SPSSWIN 10.0 program for the descriptive statistics, correlation coefficient, standardized mortality ratio(SMR), validity index(sensitivity, specificity, positive predictive value, negative predictive value), and AUC of ROC curve. Result: The mortality rate was 10.9% (60 cases) and the predicted death rate was 9.5%. The correlation coefficient(r) between observed and expected death rates was .929(p<.01) and SMR was 1.15. Se, Sp, pPv, nPv, and the correct classification rate were .80, .96, .70, .98, and 94.0% respectively. In addition, areas under the curve (AUC) of the receiver operating characteristic(ROC) was 0.954 (95% CI=0.919～0.989). According to demographic characteristics, mortality was underestimated in the medical group and overestimated in the surgical group. In addition, the AUCs of ROC curve were generally high in all subgroups. Conclusion: The PIM Ⅱ showed a good, so it can be utilized for the subject hospital. better.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.55 no.5
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• pp.240-247
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• 2006

Frequent arousals during sleep degrade the quality of sleep and result in sleep fragmentation. Visual inspection of physiological signals to detect the arousal events is cumbersome and time-consuming work. The purpose of this study is to develop an automatic algorithm to detect the arousal events. The proposed method is based on time-frequency analysis and the support vector machine classifier using single channel electroencephalogram (EEG). To extract features, first we computed 6 indices to find out the informations of a subject's sleep states. Next powers of each of 4 frequency bands were computed using spectrogram of arousal region. And finally we computed variations of power of EEG frequency to detect arousals. The performance has been assessed using polysomnographic (PSG) recordings of twenty patients with sleep apnea, snoring and excessive daytime sleepiness (EDS). We could obtain sensitivity of 79.65%, specificity of 89.52% for the data sets. We have shown that proposed method was effective for detecting the arousal events.