• Tuberculosis and Respiratory Diseases
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• 제81권4호
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• pp.339-346
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• 2018

Background: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a standard procedure to evaluate suspicious lymph node involvement of lung cancer because computed tomography (CT) and $^{18}F$-fluorodeoxyglucose positron emission tomography-CT (PET-CT) have limitations in their sensitivity and specificity. There are a number of benign causes of false positive lymph node such as anthracosis or anthracofibrosis, pneumoconiosis, old or active tuberculosis, interstitial lung disease, and other infectious conditions including pneumonia. The purpose of this study was to evaluate possible causes of false positive lymph node detected in chest CT or PET-CT. Methods: Two hundred forty-seven patients who were initially diagnosed with lung cancer between May 2009 and December 2012, and underwent EBUS-TBNA to confirm suspicious lymph node involvement by chest CT or PET-CT were analyzed for the study. Results: Of 247 cases, EBUS-TBNA confirmed malignancy in at least one lymph node in 189. The remaining 58 patients whose EBUS-TBNA results were negative were analyzed. Age ${\geq}65$, squamous cell carcinoma as the histologic type, and pneumoconiosis were related with false-positive lymph node involvement on imaging studies such as chest CT and PET-CT. Conclusion: These findings suggest that lung cancer staging should be done more carefully when a patient has clinically benign lymph node characteristics including older age, squamous cell carcinoma, and benign lung conditions.

• Asian Pacific Journal of Cancer Prevention
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• 제15권2호
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• pp.569-575
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• 2014

Although mammography is the primary imaging modality for the breast, it has its limitations especially with dense breast parenchyma. Breast magnetic resonance imaging (MRI) has evolved into an important adjunctive tool as it is currently the most sensitive technique for breast cancer detection. Despite this high sensitivity, overlap in the appearances of some benign and malignant breast lesions results in additional unnecessary intervention with negative results. These false positives, in addition to high cost and limited availability, necessitate establishing proper indications for breast MRI. The literature was here reviewed for recent clinical trials, meta-analyses and review papers which have studied this important subject. PubMed; the US national library of medicine, was utilized to review the literature in the last twenty years. Using the obtained information, current uses of breast MRI are discussed in this paper to determine the indications which are relevant to clinical practice.

• Parasites, Hosts and Diseases
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• 제53권2호
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• pp.147-154
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• 2015

Various constituents in clinical specimens, particularly feces, can inhibit the PCR assay and lead to false-negative results. To ensure that negative results of a diagnostic PCR assay are true, it should be properly monitored by an inhibition control. In this study, a cloning vector harboring a modified target DNA sequence (${\approx}375bp$) was constructed to be used as a competitive internal amplification control (IAC) for a conventional PCR assay that detects ${\approx}550bp$ of the Cryptosporidium oocyst wall protein (COWP) gene sequence in human feces. Modification of the native PCR target was carried out using a new approach comprising inverse PCR and restriction digestion techniques. IAC was included in the assay, with the estimated optimum concentration of 1 fg per reaction, as duplex PCR. When applied on fecal samples spiked with variable oocysts counts, ${\approx}2$ oocysts were theoretically enough for detection. When applied on 25 Cryptosporidium-positive fecal samples of various infection intensities, both targets were clearly detected with minimal competition noticed in 2-3 samples. Importantly, both the analytical and the diagnostic sensitivities of the PCR assay were not altered with integration of IAC into the reactions. When tried on 180 randomly collected fecal samples, 159 were Cryptosporidium-negatives. Although the native target DNA was absent, the IAC amplicon was obviously detected on gel of all the Cryptosporidium-negative samples. These results imply that running of the diagnostic PCR, inspired with the previously developed DNA extraction protocol and the constructed IAC, represents a useful tool for Cryptosporidium detection in human feces.

• Asian Pacific Journal of Cancer Prevention
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• 제15권1호
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• pp.423-426
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• 2014

Aim: To evaluate the agreement between colposcopic diagnosis and cervical pathology a retrospective chart review was performed. Materials and Methods: This study included 437 patients who underwent colposcopy and cervical biopsy or conization at Siriraj Hospital from October 2010 - December 2012. The patient clinical characteristics, cervical cytology results, colposcopic diagnoses, cervical pathology results were recorded and correlations between variables were analyzed. Results: Agreement of colposcopic diagnosis and cervical pathology was matched in 253 patients (57.9%). The strength of agreement with weighted Kappa statistic was 0.494 (p<0.001). Colposcopic diagnoses more often overestimated (31.1%) than underestimated (11%) the cervical pathology. Agreement of colposcopic diagnosis and cervical pathology within 1 grade was found in 411 patients (94.1%). Positive predictive value (PPV) of high grade colposcopy or more was 75.5%, whereas the negative predictive value (NPV) of insignificant and low grade colposcopy was 83.8%. False positives of high grade colposcopy or more were 21%. False negatives of insignificant or low grade colposcopy were 19.1%. Conclusions: Strength of agreement between colposcopic diagnosis and cervical pathology was found to be only moderate. A biopsy at colposcopy should be performed at a gold standard level to detect high grade lesions.

• 대한의생명과학회지
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• 제21권1호
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• pp.9-14
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• 2015

Mouse hepatitis virus (MHV) is a major pathogen in laboratory mice that usually leads to fatal diseases, such as hepatitis, multiple sclerosis, encephalitis, and respiratory disease. MHV has a high infection rate, and it needs to be detected as soon as possible to prevent its spread to other facilities. However, MHV detection by enzyme-linked immunosorbent assay (ELISA) often gives false positives; thus, it is very important that the results are confirmed as true positives in the early infection stage or distinguished as false positives with more accurate, reliable methods. Under microbiological screening, MHV ELISA-positive mice were found in four GFP-tagging transgenic mice. To verify the detection of the MHV antigen directly, reverse transcription polymerase chain reaction (RT-PCR) was performed, and the mice were determined to be MHV negative. Additional serum antibody-based screening was conducted with three different ELISA kits, and multiplexed fluorometric immunoassay (MFIA) was performed to confirm their accuracy/sensitivity. In brief, the ELISA kit for A59 nucleocapsid protein (MHV-A59N) revealed MHV ELISA positivity, while other ELISA kits (MHV-S lysate and MHV-JHM lysate) demonstrated MHV negativity. In MFIA, only the test for the recombinant A59 nucleocapsid antigen was MHV positive, which was consistent with the ELISA results. These results suggest that the ELISA kit with the recombinant A59 nucleocapsid antigen might induce non-specific MHV ELISA positivity and that confirmation is therefore essential.

• 핵의학기술
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• 제14권2호
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• pp.60-64
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• 2010

유방암의 진단을 위해 단순유방촬영, 유방초음파검사, $^{18}F$-FDG PET 검사가 대부분 함께 이루어지고 있다. 그러나 이들 검사의 단점을 보완하고자 보다 더 높은 예민도, 특이도, 정확도를 가진 PEM이 도입되었다. 본 연구에서는 유방암의 진단을 향상시키는 PEM의 유용성을 알아보고자한다. 2010년 1월부터 3월까지 유방외과에서 유방암 진단을 받은 환자 100명을 대상으로 PEM 검사를 시행하였다. 장비는 Naviscan사의 PEM Flex Solo II scanner를 사용하였다. PEM 영상결과와 수술 후 병리결과를 비교하여 PEM 검사의 예민도, 특이도, 정확도를 평가하였다. 환자 100명에서 PEM 영상과 수술 후 병리결과를 통해 알아본 결과로 진양성은 89, 위양성은 9, 위음성은 7, 진음성은 87이었다. PEM 검사의 예민도, 특이도, 정확도는 각각 92.7%, 90.6%, 91.7%로 나타났다. 단순유방촬영에서 예민도 86.2%, 특이도 64.5%로 보고되어 있고 유방초음파검사에서 예민도 87.9%, 특이도 76.7%로 알려져 있다. 본 연구에서 PEM은 예민도 92.7%, 특이도 90.6%로 다른 검사보다 높게 나타났다. 이로써 PEM은 유방암을 진단하고 수술하기 전의 더 나은 수술 계획에 사용될 수 있으며 국소 부위 재발의 발견에 도움이 될 것으로 사료된다.

• 보건의료산업학회지
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• 제10권2호
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• pp.155-166
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• 2016

Objectives : This study confirmed the limitation of long-term care insurance by analyzing media contents. Methods : Articles and reviews were searched with the article searching system (KINDS) from July 2008 to December, 2015. Results : Among the 155 articles examined, 61.1% highlighted the faults of suppliers, and 25.2% indicated the responsibility of the insurer. As for their purpose, 56.8% reported on accidents, and 32.3% provided information. Furthermore, 74.2% reported on negative contents and only 25.8% on neutral contents. The negative contents consisted of requesting false insurance benefits, amending the range and price indicating the very low salaries of the care givers, limitations on the care grade assessment, and problems related with assistive devices. The majority of neutral articles is for providing information. Conclusions : There were many problems starting from the early stage of the insurance. We must pay attention to these problems. Moreover, we should try to handle and prevent these problems with supportive responses from authorities.

• ETRI Journal
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• 제39권5호
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• pp.621-631
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• 2017

Abnormal samples are usually difficult to obtain in production systems, resulting in imbalanced training sample sets. Namely, the number of positive samples is far less than the number of negative samples. Traditional Support Vector Machine (SVM)-based anomaly detection algorithms perform poorly for highly imbalanced datasets: the learned classification hyperplane skews toward the positive samples, resulting in a high false-negative rate. This article proposes a new imbalanced SVM (termed ImSVM)-based anomaly detection algorithm, which assigns a different weight for each positive support vector in the decision function. ImSVM adjusts the learned classification hyperplane to make the decision function achieve a maximum GMean measure value on the dataset. The above problem is converted into an unconstrained optimization problem to search the optimal weight vector. Experiments are carried out on both Cloud datasets and Knowledge Discovery and Data Mining datasets to evaluate ImSVM. Highly imbalanced training sample sets are constructed. The experimental results show that ImSVM outperforms over-sampling techniques and several existing imbalanced SVM-based techniques.

• International journal of advanced smart convergence
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• 제12권1호
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• pp.82-91
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• 2023

In 2020 when the COVID-19 pandemic began in full-scale, the WHO Director-General warned of the dangers of an infodemic. The infodemic is a phenomenon in which false information spreads rapidly like an epidemic and causes chaos, and it was noted that the COVID-19 pandemic is not just limited to health problems, but also linked to a variety of issues such as human rights, economic inequality, various discrimination, hate speech, fake news, global governance etc. In the field of education, it is necessary to think about how to connect this global situation with school classes. Accordingly, this study suggested the direction for global citizenship education by analyzing how the infodemic spreads on Korean social media with the case of the recent global COVID-19 pandemic. According to the research results, the rate of negative emotions was higher than positive ones in the emotions that generate infodemic, while anxiety and anger were focused among negative emotions. In addition, the infodemic tended to spread widely with the feelings of anger rather than anxiety, and the feelings of anger led to advocating aggressive policies against certain country and regions. Therefore, global citizenship education is required to focus on a sense of duty and responsibility as a citizen, not on the level of national identity based on an exclusive sense of belonging. Furthermore, global citizenship education needs to lead to presenting a blueprint for education in a way that can enhance the awareness of the global community for joint response to global challenges and realize common prosperity based on sustainability and justice.

• 한국음향학회지
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• 제41권4호
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• pp.468-479
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• 2022

수중에서 능동소나를 이용하여 표적을 탐지하기 위하여, 송신음이 표적에 반사된 반향을 수신함으로써 표적의 위치를 감지한다. 이때 산란체로부터의 잔향이 발생하며, 이는 표적 반향의 탐지를 방해하게 된다. 효과적인 표적 탐지를 위해 자기회귀 모델기반의 백색화 기법이나 주성분역산 등의 잔향 제거 기법이 연구된 바 있으며, 최근에는 비음수 행렬 분해 기반의 기법이 고안되었다. 비음수 행렬 분해 기반의 잔향 제거 기법은 기존의 기법에 비해 향상된 성능을 보여주지만, 송수신기의 위치 및 거리에 의한 감쇠 등이 고려되지 않았다. 본 논문에서는, 양상태 소나에서 지속파 송신 파형을 사용하는 경우에 대하여 수신기의 방향성과 그에 관련된 도플러, 그리고 거리에 대한 감쇠 등의 전처리를 통해 성능을 개선하였다. 본 연구에서 고안된 시스템의 성능을 확인하기 위하여 잔향 모델을 이용한 시뮬레이션을 수행하였다, 시뮬레이션 결과 1 %의 낮은 오탐지율에서 기존의 비음수 행렬 분해 기법 대비 10 % ~ 40 %의 탐지율 성능 향상이 있음을 확인하였다.