• 분석과학
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• 제21권6호
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• pp.480-486
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• 2008

본 연구에서는 시중에 유통중인 광물성 생약에서의 중금속(Pb, Cd, As, Hg)에 대해 모니터링 하였다. Pb, Cd, As의 경우 시료 전처리는 습식분해법으로 하였으며, ICP-MS를 이용하여 검출하였고 Hg의 경우 AMA를 이용하여 모니터링 하였다. 모니터링의 결과 전체 시료(92)의 25.81%(24)가 Pb를 함유하고 있었으며 능자광(85.5 mg/kg), 부석(41.2 mg/kg), 진사(20.4 mg/kg)에서 기준치(0.5 mg/kg) 이상으로 검출되었다. Cd의 경우 전체 시료(92)의 9.68%(17)가 함유되어있었으며, 능자광(345 mg/kg), 부석(0.44 mg/kg), 진사(2.78 mg/kg)에서 기준치(0.3 mg/kg) 이상으로 검출되었고, 전체 시료(92)의 24.73%(23)가 As를 함유하고 있었으며, 능자광(5.72 mg/kg), 조산화납(22.2 mg/kg), 황화제이수은(10.0 mg/kg), 진사(12.5 mg/kg), 흑운모(14.6 mg/kg)에서 기준치(3 mg/kg)이상으로 검출되었다. Hg의 경우는 전체 시료(92)의 76.34%(78)가 함유되어 있었으며, 전체 13 종 광물 중 10종에서 기준치(0.2 mg/kg) 이상으로 검출되었다. 따라서, 국내에 유통되고 있는 광물성 생약재의 품질 평가와 안전관리를 보완하여 광물성 생약에 대한 신뢰성과 안전성을 확보할 필요성이 있는 것으로 판단된다.

• 대순사상논총
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• 제17권
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• pp.173-196
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• 2004

Miroku belief observed in Japanese folklore and popular religions is originated from the faith in a bodhisattva called Miroku (Maitreya) who, depending on Buddhist account, is supposed to appear in this world to save all mankind. This faith, together with the millenarianism inherent in it, was disseminated into many areas of East and Southeast Asia. It developed in various ways, being associated with the religious tradition of each area where it was accepted. In Japanese folklore and popular religions the aspiration for the "World of Miroku", the ideal world expected to be realized in the future, has been its most notable feature. This paper examines the notion of the "World of Miroku" developed in the cult of Mount Fuji in early modern Japan. In particular this paper focuses on the "World of Miroku" appearing in the teachings of Fuji-ko and Fujido, which were the organizations of lay believers. Through the examination this paper made the following facts clear. (1) The notion of the "World of Miroku" developed by Fuji-ko and Fujido had its bases in Miroku belief of Japanese folklore. (2) However the notion of the "World of Miroku" in the teachings of Fuji-ko and Fujido was quite different from that of the folklore. While the "World of Miroku" appearing in the folklore is characterized by good harvest and abundant gold and silver, Fuji-ko and Fujido leaders thought that all people, including the emperor and the shogun, would earnestly carry out their house business, do their best to promote the happiness of the others, and pray for the salvation of all mankind in the "World of Miroku". (3) The notion about the changes of the world, which was particular to Fuji-ko and Fujido, accounts for such development in the concept of the "World of Miroku". According to the notion the current world was recognized as the second stage, between the original world in the past and the "World of Miroku" in the future, in the history of human beings. This idea helped the leaders of Fuji-ko and Fujido to develop the theories of world renewal, in which the wrong doings of the rulers and poor morality of the people were to be corrected in the "World of Miroku". (4) One of the most important features of the "World of Miroku" was the equality between men and women according to the teachings of Fujido. Both Fuji-ko and Fujido had opposed to the prevailing view of women, in which women were regarded as being sinful and polluted. Fujido further tried to improve the status of women in their families and the society. (5) In accordance with such an innovatory view, Fujido challenged the custom of excluding women from sacred places, Mount Fuji in particular. Through clarifying these facts this paper shows that Miroku belief could function as a basis for developing the ideas concerning the world renewal in early modern Jap

• 마이크로전자및패키징학회지
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• 제30권4호
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• pp.61-68
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• 2023

무연솔더에 Fe 입자를 첨가하여 Cu₃Sn 금속간화합물 성장을 억제하고 취성파괴를 방지하는 연구는 보고된 바 있으나 이러한 복합솔더를 TLP(transient liquid phase) 본딩에 적용한 경우는 아직 없다. 본 연구에서는 Sn계 무연솔더 내부에 Fe 입자의 함량을 적절히 조절하여 Sn-3.5Ag-15.0Fe 복합솔더를 제작하고 TLP 본딩에 적용하여 접합부 전체를 Sn-Fe 금속간화합물로 변화시킴으로써 고온 솔더로서의 적용 가능성을 탐색하였다. 접합공정 중에 형성되는 FeSn₂ 금속간화합물은 513℃의 고융점을 가지므로 사용 중 온도가 280℃까지 상승하는 전력반도체용 파워모듈에 안정적으로 적용이 가능하다. 칩과 기판에 ENIG(electroless nickel-immersion gold) 표면처리를 적용한 결과 접합부에 Ni₃Sn₄/FeSn₂/Ni₃Sn₄의 다층 금속간화합물 구조를 형성하였으며 전단시험시 파괴경로는 Ni₃Sn₄/FeSn₂ 계면에서 균열이 진전하다가 FeSn₂ 내부로 전파되는 양상을 보였다. TLP 접합공정 2시간 이후에는 30 MPa 이상의 전단강도를 얻었고 특히 200℃ 전단시험에서도 강도 저하가 전혀 없었다. 본 연구결과는 최근 활발히 연구되고 있는 전기자동차용 파워모듈에 적용할 수 있는 소재 및 공정으로 기대할 수 있다.

• Korean Journal of Radiology
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• 제22권3호
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• pp.344-353
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• 2021

Objective: The mitotic count of gastrointestinal stromal tumors (GIST) is closely associated with the risk of planting and metastasis. The purpose of this study was to develop a predictive model for the mitotic index of local primary GIST, based on deep learning algorithm. Materials and Methods: Abdominal contrast-enhanced CT images of 148 pathologically confirmed GIST cases were retrospectively collected for the development of a deep learning classification algorithm. The areas of GIST masses on the CT images were retrospectively labelled by an experienced radiologist. The postoperative pathological mitotic count was considered as the gold standard (high mitotic count, > 5/50 high-power fields [HPFs]; low mitotic count, ≤ 5/50 HPFs). A binary classification model was trained on the basis of the VGG16 convolutional neural network, using the CT images with the training set (n = 108), validation set (n = 20), and the test set (n = 20). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated at both, the image level and the patient level. The receiver operating characteristic curves were generated on the basis of the model prediction results and the area under curves (AUCs) were calculated. The risk categories of the tumors were predicted according to the Armed Forces Institute of Pathology criteria. Results: At the image level, the classification prediction results of the mitotic counts in the test cohort were as follows: sensitivity 85.7% (95% confidence interval [CI]: 0.834-0.877), specificity 67.5% (95% CI: 0.636-0.712), PPV 82.1% (95% CI: 0.797-0.843), NPV 73.0% (95% CI: 0.691-0.766), and AUC 0.771 (95% CI: 0.750-0.791). At the patient level, the classification prediction results in the test cohort were as follows: sensitivity 90.0% (95% CI: 0.541-0.995), specificity 70.0% (95% CI: 0.354-0.919), PPV 75.0% (95% CI: 0.428-0.933), NPV 87.5% (95% CI: 0.467-0.993), and AUC 0.800 (95% CI: 0.563-0.943). Conclusion: We developed and preliminarily verified the GIST mitotic count binary prediction model, based on the VGG convolutional neural network. The model displayed a good predictive performance.

• 한국해양학회지:바다
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• 제13권3호
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• pp.271-279
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• 2008

해저열수광상은 황화물 미네랄이 해저의 열수작용을 통해 형성된 광상을 의미하며 특히, 구리, 납, 아연, 금, 은 등의 금속이 다량 포함되어 있다. 현재 해저열수광상 개발분야의 선두주자는 노틸러스사이다. 노틸러스사는 파푸아뉴기니, 피지, 통가, 솔로몬제도, 뉴질랜드 등 남서태평양 도서국에 약 37만 $km^2$에 달하는 탐사권을 보유 또는 신청해 놓은 상태이다. 넵튠사 역시 뉴질랜드, 파푸아뉴기니, 마이크로네시아에서 27만 $km^2$가 넘는 면적의 탐사권을 취득하였다. 이들 두 광업회사는 2010년 세계 최초로 해저열수광상의 상업생산을 목표로 적극적인 활동을 전개하고 있다. 주변국가인 중국과 일본은 전략광물의 안정적 공급을 위하여 해저열수광상 탐사활동을 적극적으로 수행하고 있는 실정이다. 중국의 경우 중국대양협회를 통해 전 지구 대양을 대상으로 심해저자원개발을 위한 국가연구개발사업을 수행하고 있다. 일본의 경우 자국의 EEZ를 중심으로 해저열수광상 조사사업을 수행하고 있다. 이러한 국제적인 해저열수광상 개발동향을 고려하여 우리나라의 해저열수광상 개발을 위한 전략방향을 소관부처의 일원화와 법제도 정비, 사업추진주체 결정, 정부의 적극적 예산지원, 해저열수광상 개발을 위한 중장기 계획수립 등의 측면에서 제안하였다.

• 감성과학
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• 제26권4호
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• pp.71-92
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• 2023

본 연구의 목적은 구슬 문양 디자인의 상징성과 의미 및 신라문화와의 연관성, 유리구슬 제조의 제반 여건을 조사하여 예술성과 기술성이 뛰어난 신라 인면 상감 유리구슬의 신라 자체 제작설을 검증하는 것이다. 연구방법으로는 디자인 분석 이외에 고문헌과 신화, 유리 유물, 유리 및 금속의 생산기술, 실크로드 교차로의 특성 등을 조사하였으며 홍산문화 유물, 다른 상감 유리구슬의 사례들을 수집하였다. 마한, 부여, 신라인은 구슬을 보배로 삼고 장신구에 애용하였는데, 구슬 속의 인면상 상투와 금관장식, 새와 꽃나무의 모든 디자인 요소가 김알지, 김수로, 박혁거세, 주몽 등 위인들의 난생설화, 북방의 새 및 신수 숭상 등과 밀접하였고, 디자인 요소와 배치가 신라의 다른 유물에서도 동일하게 표현되고 있음을 확인하였다. 구슬과 인면상의 기원은 홍산문화였으며 하가점하층문화의 고조선 북표에서는 구슬용 석범이 발견되었다. 또 경주 식리총의 상감 유리구슬과 일본 토간모리 고분의 인면 상감 유리구슬의 출토는 신라 자체 제작설을 확증시켜주는 것이다. 백제인이 5세기 일본에 유리구슬 제작소를 둔 사실은 신라인이 인도네시아 자바에도 제작소를 두었음을 의미한다. 신라와 밀접한 관계였던 인도네시아 자바는 신라의 해상실크로드 교차로, 원석 및 노동력 제공지이고 유리구슬의 소비 지역이나 기원지는 아니었다. 이에 구슬에 대한 신화와 전통을 보유하고 머리에 상투와 금관을 착용하였으며, 금속 및 상감 기술 등 난이도 높은 기술을 보유했던 신라가 자체 제작한 것이 틀림없다.

• Korean Circulation Journal
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• 제53권7호
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• pp.425-451
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• 2023

Most patients with heart failure (HF) have multiple comorbidities, which impact their quality of life, aggravate HF, and increase mortality. Cardiovascular comorbidities include systemic and pulmonary hypertension, ischemic and valvular heart diseases, and atrial fibrillation. Non-cardiovascular comorbidities include diabetes mellitus (DM), chronic kidney and pulmonary diseases, iron deficiency and anemia, and sleep apnea. In patients with HF with hypertension and left ventricular hypertrophy, renin-angiotensin system inhibitors combined with calcium channel blockers and/or diuretics is an effective treatment regimen. Measurement of pulmonary vascular resistance via right heart catheterization is recommended for patients with HF considered suitable for implantation of mechanical circulatory support devices or as heart transplantation candidates. Coronary angiography remains the gold standard for the diagnosis and reperfusion in patients with HF and angina pectoris refractory to antianginal medications. In patients with HF and atrial fibrillation, longterm anticoagulants are recommended according to the CHA₂DS₂-VASc scores. Valvular heart diseases should be treated medically and/or surgically. In patients with HF and DM, metformin is relatively safer; thiazolidinediones cause fluid retention and should be avoided in patients with HF and dyspnea. In renal insufficiency, both volume status and cardiac performance are important for therapy guidance. In patients with HF and pulmonary disease, beta-blockers are underused, which may be related to increased mortality. In patients with HF and anemia, iron supplementation can help improve symptoms. In obstructive sleep apnea, continuous positive airway pressure therapy helps avoid severe nocturnal hypoxia. Appropriate management of comorbidities is important for improving clinical outcomes in patients with HF.

• Korean Journal of Radiology
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• 제25권6호
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• pp.575-588
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• 2024

Objective: Differentiating intracranial aneurysms from normal variants using CT angiography (CTA) or MR angiography (MRA) poses significant challenges. This study aimed to evaluate the efficacy of proton-density MRA (PD-MRA) compared to high-resolution time-of-flight MRA (HR-MRA) in diagnosing aneurysms among patients with indeterminate findings on conventional CTA or MRA. Materials and Methods: In this retrospective analysis, we included patients who underwent both PD-MRA and HR-MRA from August 2020 to July 2022 to assess lesions deemed indeterminate on prior conventional CTA or MRA examinations. Three experienced neuroradiologists independently reviewed the lesions using HR-MRA and PD-MRA with reconstructed voxel sizes of 0.25³ mm³ or 0.2³ mm³, respectively. A neurointerventionist established the gold standard with digital subtraction angiography. We compared the performance of HR-MRA, PD-MRA (0.25³-mm³ voxel), and PD-MRA (0.2³-mm³ voxel) in diagnosing aneurysms, both per lesion and per patient. The Fleiss kappa statistic was used to calculate inter-reader agreement. Results: The study involved 109 patients (average age 57.4 ± 11.0 years; male:female ratio, 11:98) with 141 indeterminate lesions. Of these, 78 lesions (55.3%) in 69 patients were confirmed as aneurysms by the reference standard. PD-MRA (0.25³-mm³ voxel) exhibited significantly higher per-lesion diagnostic performance compared to HR-MRA across all three readers: sensitivity ranged from 87.2%-91.0% versus 66.7%-70.5%; specificity from 93.7%-96.8% versus 58.7%-68.3%; and accuracy from 90.8%-92.9% versus 63.8%-69.5% (P ≤ 0.003). Furthermore, PD-MRA (0.25³-mm³ voxel) demonstrated significantly superior per-patient specificity and accuracy compared to HR-MRA across all evaluators (P ≤ 0.013). The diagnostic accuracy of PD-MRA (0.2³-mm³ voxel) surpassed that of HR-MRA and was comparable to PD-MRA (0.25³-mm³ voxel). The kappa values for inter-reader agreements were significantly higher in PD-MRA (0.820-0.938) than in HR-MRA (0.447-0.510). Conclusion: PD-MRA outperformed HR-MRA in diagnostic accuracy and demonstrated almost perfect inter-reader consistency in identifying intracranial aneurysms among patients with lesions initially indeterminate on CTA or MRA.

• Korean Journal of Radiology
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• 제23권1호
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• pp.77-88
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• 2022

Objective: Our study aimed to evaluate the quality of radiomics studies on brain metastases based on the radiomics quality score (RQS), Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) checklist, and the Image Biomarker Standardization Initiative (IBSI) guidelines. Materials and Methods: PubMed MEDLINE, and EMBASE were searched for articles on radiomics for evaluating brain metastases, published until February 2021. Of the 572 articles, 29 relevant original research articles were included and evaluated according to the RQS, TRIPOD checklist, and IBSI guidelines. Results: External validation was performed in only three studies (10.3%). The median RQS was 3.0 (range, -6 to 12), with a low basic adherence rate of 50.0%. The adherence rate was low in comparison to the "gold standard" (10.3%), stating the potential clinical utility (10.3%), performing the cut-off analysis (3.4%), reporting calibration statistics (6.9%), and providing open science and data (3.4%). None of the studies involved test-retest or phantom studies, prospective studies, or cost-effectiveness analyses. The overall rate of adherence to the TRIPOD checklist was 60.3% and low for reporting title (3.4%), blind assessment of outcome (0%), description of the handling of missing data (0%), and presentation of the full prediction model (0%). The majority of studies lacked pre-processing steps, with bias-field correction, isovoxel resampling, skull stripping, and gray-level discretization performed in only six (20.7%), nine (31.0%), four (3.8%), and four (13.8%) studies, respectively. Conclusion: The overall scientific and reporting quality of radiomics studies on brain metastases published during the study period was insufficient. Radiomics studies should adhere to the RQS, TRIPOD, and IBSI guidelines to facilitate the translation of radiomics into the clinical field.

• Korean Journal of Radiology
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• 제20권1호
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• pp.114-125
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• 2019

Objective: Segmented cardiac cine magnetic resonance imaging (MRI) is the gold standard for cardiac ventricular volumetric assessment. In patients with difficulty in breath-holding or arrhythmia, this technique may generate images with inadequate quality for diagnosis. Real-time cardiac cine MRI has been developed to address this limitation. We aimed to assess the performance of retrospective electrocardiography-gated real-time cine MRI at 3T for left ventricular (LV) volume and mass measurement. Materials and Methods: Fifty-one patients were consecutively enrolled. A series of short-axis cine images covering the entire left ventricle using both segmented and real-time balanced steady-state free precession cardiac cine MRI were obtained. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), and LV mass were measured. The agreement and correlation of the parameters were assessed. Additionally, image quality was evaluated using European CMR Registry (Euro-CMR) score and structure visibility rating. Results: In patients without difficulty in breath-holding or arrhythmia, no significant difference was found in Euro-CMR score between the two techniques (0.3 ± 0.7 vs. 0.3 ± 0.5, p > 0.05). Good agreements and correlations were found between the techniques for measuring EDV, ESV, EF, SV, and LV mass. In patients with difficulty in breath-holding or arrhythmia, segmented cine MRI had a significant higher Euro-CMR score (2.3 ± 1.2 vs. 0.4 ± 0.5, p < 0.001). Conclusion: Real-time cine MRI at 3T allowed the assessment of LV volume with high accuracy and showed a significantly better image quality compared to that of segmented cine MRI in patients with difficulty in breath-holding and arrhythmia.