• 한국환경보건학회지
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• 제50권1호
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• pp.36-42
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• 2024

Background: The use of scented candles and incense sticks, both of which are household products that are burned for indoor deodorization and calming effects, is increasing. Fine dust has been designated as a group 1 carcinogen by the International Agency for Research on Cancer. Volatile organic compounds (VOCs) affect air pollution and can cause diseases. Objectives: This study aims to determine the effect on indoor air quality by measuring PM_2.5 and VOCs generated when burning scented candles and incense sticks. Methods: Scented candles and incense sticks were selected as household products to burn. As for the target sample, top-selling products (five types of scented candles, five types of incense sticks) were purchased online. The PM_2.5 concentration according to time was measured immediately next to the sample and three meters away from each other in an enclosed space using a real-time aerosol photometer. VOCs were collected as samples under the same conditions using Tenax tubes and were quantitatively analyzed by TD-GC/MS. Results: In the case of scented candles, the concentration of PM_2.5 did not increase during combustion and after being extinguished by placing a cover on the candle. For the incense sticks, the concentration of PM_2.5 averaged 1,901.27 ㎍/m³. After burning scented candles and incense sticks, some VOCs concentrations were increased such as ethyl acetate and BTEX (benzene, toluene, ethylbenzene, xylene). Conclusions: Therefore, when using scented candles, extinguishment by placing a cover on the candle can be expected to reduce PM_2.5. It is advisable to avoid using incense sticks because PM_2.5 concentration increases from the start of combustion.

• 한국해양학회지:바다
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• 제13권2호
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• pp.106-111
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• 2008

해양생태독성평가를 위한 공정시험방법으로서 해양생태계의 분해자, 기초생산자 및 소비자를 대표하는 6개 생물군을 이용하여 각각의 생물에 대한 생태독성시험용 표준시험방법(standard methods)을 개발 또는 정립하였다. 본 시험방법은 미환경보호국, 국제기구 및 유럽국가의 표준시험방법을 참고하였으며, 독성시험에 사용되는 표준시험생물은 우리나라에 서식하는 해양성 또는 광염성 생물(euryhaline species)로 선정하였다. 각 시험방법은 표준시험생물의 배양 및 사육, 시험방법 및 과정, 시험의 재현성 및 적합도 기준 등을 포함한다. 표준시험생물은 총 9종으로서 해산발광박테리아(Vibrio fischeri), 해산규조류(Skeletonema costatum), 녹조구멍갈파래(Ulva pertusa), 해산윤충류(Brachionus plicatilis), 저서요각류(Tigriopus japonicus), 저서단각류 2종(Mandibulophoxus mai and Monocorophium acherusicum) 및 어류 2종(Oryzias latipes and Paralichthys olivaceus)을 포함한다. 표준시험생물은 해양생태계의 기초생산자, 분해자 및 소비자를 대표하며, 생태독성 시험시 각 영양 단계별 최소 1종을 포함하는 총 3종의 "battery test"를 권장한다.

• Korean Chemical Engineering Research
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• 제62권1호
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• pp.80-86
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• 2024

본 연구는 고체 바이오연료 생산용 원료로서 유채대의 상용화 가능성을 평가하기 위하여 수행하였다. 대형 플라스틱통에 넣은 유채대를 1% 농도의 초산 수용액에 침지하여 단리된 환원당의 함량을 분석한 결과, glucose의 함량이 가장 높았으며, 다음으로 xylose, galactose, arabinose, mannose 순으로 조사되었다. 파일럿 규모의 평다이 펠릿성형기를 이용하여 무침지 및 침지 유채대로 연료용 펠릿으로 제조하였다. 펠릿의 겉보기밀도와 발열량은 침지처리 및 목분의 혼합과 함께 증가하였으며, 이 측정치는 International Organization for Standardization(ISO)의 비목재펠릿 A 등급 기준을 크게 상회하였다. 회분 함량도 침지처리와 함께 감소하여 ISO의 A등급 기준을 만족하였다. 펠릿 내구성의 경우, 유채대의 침지처리로 증가하였으며, 펠릿 제조에 목분의 첨가와 함께 향상되었다. 그러나 그 측정치는 ISO의 B등급 기준(≧96.0%)에 미치지 못하였다. 따라서 초산 수용액 침지 유채대로 생산할 비목재 펠릿의 상용화를 위하여 내구성 향상을 위한 바인더의 사용이 필요하다는 결론을 얻었다.

• 한방재활의학과학회지
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• 제34권2호
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• pp.101-134
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• 2024

Objectives The purpose of this study is to observe the effectiveness of acupotomy treatment for lateral epicondylitis by comparing it with various control groups. Methods We searched 11 domestic and international databases for systematic reviews and meta-analysis. The subjects were studies published from January 1, 2017 to September 1, 2023, and only randomised controlled trials were included. Results 208 studies were searched, of which 21 studies were finally selected. Among the studies published after 2017, the largest number of studies was published in 2019. The average number of participants per study was 72.28±20.26 and the average age was in the 40s. The most frequent intervention in the study was acupotomy alone, and the treatment most often mentioned as a control group was local nerve block. The most used evaluation tool is efficiency. Acupotomy+manipulation had statistically better effect than that of local nerve block in terms of pain (standard mean difference -1.87, 95% confidence interval, -2.18 to -1.57, p<0.00001) and elbow joint function (standard mean difference 2.25, 95% confidence interval, 1.65 to 2.86, p<0.00001). Conclusions As a result of the meta-analysis, the effect of acupotomy added manual therapy treatment was statistically significant compared to the local nerve block frequently used for lateral epicondylitis. Based on these results, it appears that more research on combination treatments other than acupotomy treatment will be needed. Also, it appears that more large-scale randomized controlled studies that strictly adhere to the standards for reporting interventions in controlled trials of acupuncture, risk of bias 2 criteria will be needed.

• Acta Via Serica
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• 제8권2호
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• pp.25-52
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• 2023

The astronomic observatory of Graw Village is located on Mount Dari Lolikan, facing the village. Graw is located in the foothills of Mount Ser-i-Rash, 25 km northeast of Erbil Governorate, Iraq. This study attempts to clarify the foundations of this observatory, its components, as well as the founder and the date of its establishment. The study made efforts to clarify the benefits of this calendar to local residents in their daily lives. The database for this study is based on direct observation of the observatory station. The observation included the recording date and position of sunset and the appearance of stars throughout the year. Observation and documentation for both sunset and stars were performed over several years due to weather conditions since observation was not possible on foggy and rainy days and nights. Each observation took five to ten minutes depending on the clarity of the sky. The observatory consists of a group of stone cones. Each cone was built by stones in a specific location after careful and long observation of the sunset. Efforts were made to observe the disappearance and reappearance of the stars based on the change in the position of the Earth in relation to the sun. Graw's calendar helped to recognize important times of the year, such as the winter and summer forties, which were very important, especially when snow covered the roads, transportation stopped, crops spoiled, and pets stayed in their barn. The most important features of the winter forties are the memories, experiences, and minds of the villagers' ancestors. The forties were associated with the arrival of cold and heavier rain throughout the year, which is consistent with modern science, as the angle at which the Earth rotates increases the number and activity of weather depressions that affect the study area during this period. This observatory has a close connection with the daily life of the villagers, especially in the past centuries. It helped the people of the area in their appointments to carry out their work in the field of agriculture. The observatory was also of great importance in the field of education in the past centuries, especially in traditional religious schools. It also appears from this research that the calendar has ancient roots, which extend back thousands of years, as evidenced by the Ezidis who follow an ancient religion whose roots extend back thousands of years and who fast during both the winter and summer forties annually, with the participation of people in various regions of the world. It is not known who made this astronomic observatory but most of the oral information that has been passed down to us by word of mouth agrees on both Mullah Abdullah Al-Kurdi and Mullah Omar. Likely, this astronomic observatory was built around the late 17^th and early 18^th centuries.

• 경영정보학연구
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• 제22권1호
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• pp.33-57
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• 2020

블록체인 생태계의 혁신을 촉진하는 암호화폐가 여러 목적을 위해 발행됨에도 불구하고, 투자자들은 암호화폐를 시세 차익의 수단으로만 인식한다. 이는 암호화폐의 투기적 측면만을 부각해 암호화폐가 발행되는 근본적인 목적이 무시되고, 블록체인 생태계의 혁신을 방해한다. 본 연구에서는 암호화폐 투자자들의 투기적 행동 원인을 학문적 관점에서 규명한다. 개인들이 기존 주식, 벤처 투자 시 사용하는 의사결정 기준을 통합하고 암호화폐 투자 시 고려해야 할 기준을 추가해 통합하였다. 확립된 모델을 바탕으로 암호화폐에 대한 그릇된 인식의 원인을 제한된 합리성 이론으로 뒷받침한다. 의사결정 기준 정립을 위해 전통적인 벤처 및 엔젤 투자자들이 투자 의사결정 시에 사용하는 변수를 차용하고, 암호화폐 속성을 반영하기 위해 백서의 목차에서 나타난 키워드를 수집하여 암호화폐 투자에 적용 가능한 새로운 변수들을 도출하였다. 본 연구는 Simon이 제시하는 제약들로 인해 개인들이 암호화폐를 투기의 수단만으로 인식하고, 생태계의 건전성을 저해하는 비합리적인 의사결정을 행할 수밖에 없게 된다는 것을 설명한다. 이를 위해 우리는 제한된 지식과 불완전한 정보의 제약을 바탕으로 나누어진 표본이 내린 의사결정에서 합리성의 유의미한 차이가 있는지 분석한다. 그 결과, 불완전한 정보는 투자자들이 비합리적인 기준만을 고려하도록 야기했다. 이 결과로부터, 본 연구는 개인들의 합리적인 투자와 블록체인 생태계의 발전이 함께 추구되기 위해 정보 비대칭이 완화되어야 할 필요가 있음을 시사한다. 또한, 산업이 개인 투자자들의 의사결정에 대하여 더 나은 이해를 가능하게 함으로써, 추후 ICO에서 성공적인 자금 조달이 가능하도록 전략적 인사이트를 포착할 수 있다.

• Korean Circulation Journal
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• 제53권12호
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• pp.829-839
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• 2023

Background and Objectives: There is limited data on the impact of type 2 myocardial infarction (T2MI) during the coronavirus disease 2019 (COVID-19) pandemic. Methods: The National Inpatient Sample (NIS) database from January 2019 to December 2020 was queried to identify T2MI hospitalizations based on the appropriate International Classification of Disease, Tenth Revision-Clinical Modification codes. Monthly trends of COVID-19 and T2MI hospitalizations were evaluated using Joinpoint regression analysis. In addition, the multivariate logistic and linear regression analysis was used to compare inhospital mortality, coronary angiography use, and resource utilization between 2019 and 2020. Results: A total of 743,535 patients hospitalized with a diagnosis of T2MI were identified in the years 2019 (n=331,180) and 2020 (n=412,355). There was an increasing trend in T2MI hospitalizations throughout the study period corresponding to the increase in COVID-19 hospitalizations in 2020. The adjusted odds of in-hospital mortality associated with T2MI hospitalizations were significantly higher in 2020 compared with 2019 (11.1% vs. 8.1%: adjusted odds ratio, 1.19 [1.13-1.26]; p<0.01). In addition, T2MI hospitalizations were associated with lower odds of coronary angiography and higher total hospitalization charges, with no difference in the length of stay in 2020 compared with 2019. Conclusions: We found a significant increase in T2MI hospitalizations with higher in-hospital mortality, total hospitalization costs, and lower coronary angiography use during the early COVID-19 pandemic corresponding to the trends in the rise of COVID-19 hospitalizations. Further research into the factors associated with increased mortality can increase our preparedness for future pandemics.

• 대한영상의학회지
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• 제81권3호
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• pp.632-643
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• 2020

목적 자기공명영상 근거 영상표현형과 생체분자학적 아형, 유전자 발현 프로파일 근거 위험도 등 유방암 유전체 특징의 관계를 분석하고자 하였다. 대상과 방법 The Cancer Genome Atlas와 and the Cancer Imaging Archive에 공개된 자료를 이용하였다. 122개의 유방암의 자기공명영상에서 영상표현형이 추출되었다. 유전자 발현 프로파일에 따라 PAM50아형을 분류하고 위험도를 지정하였다. 영상표현형과 생체분자학적 특징의 관계를 분석하였다. 예측모델을 알아보기 위해 penalized generalized regression analysis를 이용하였다. 결과 PAM50아형은 maximum 2D diameter (p = 0.0189), degree of correlation (p = 0.0386), 그리고 inverse difference moment normalized (p = 0.0337)와 유의하게 관련이 있었다. 위험도 시스템 중에 GGI와 GENE70이 통계적으로 유의하게 8개의 영상표현형 특징을 서로 공유하였다(p = 0.0008~0.0492). Maximum 2D diameter가 두 위험도 시스템에서 가장 유의하게 관련있는 특징이었으나(p = 0.0139, p = 0.0008) 예측모델의 전반적인 연관 정도는 약했고 가장 높은 연관계수는 GENE70이 0.2171이었다. 결론 영상표현형 중에 maximum 2D diameter, degree of correlation, 그리고 inverse difference moment normalized가 PAM50 아형 그리고 GENE70과 같은 유전자 발현 프로파일 근거 위험도와 그 연관도는 약하였으나 유의한 관련을 보였다.

• Korean Journal of Radiology
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• 제25권2호
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• pp.189-198
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• 2024

Objective: To investigate the prognostic utility of radiomics features extracted from ¹⁸F-fluorodeoxyglucose (FDG) PET/CT combined with clinical factors and metabolic parameters in predicting progression-free survival (PFS) and overall survival (OS) in individuals diagnosed with extranodal nasal-type NK/T cell lymphoma (ENKTCL). Materials and Methods: A total of 126 adults with ENKTCL who underwent ¹⁸F-FDG PET/CT examination before treatment were retrospectively included and randomly divided into training (n = 88) and validation cohorts (n = 38) at a ratio of 7:3. Least absolute shrinkage and selection operation Cox regression analysis was used to select the best radiomics features and calculate each patient's radiomics scores (RadPFS and RadOS). Kaplan-Meier curve and Log-rank test were used to compare survival between patient groups risk-stratified by the radiomics scores. Various models to predict PFS and OS were constructed, including clinical, metabolic, clinical + metabolic, and clinical + metabolic + radiomics models. The discriminative ability of each model was evaluated using Harrell's C index. The performance of each model in predicting PFS and OS for 1-, 3-, and 5-years was evaluated using the time-dependent receiver operating characteristic (ROC) curve. Results: Kaplan-Meier curve analysis demonstrated that the radiomics scores effectively identified high- and low-risk patients (all P < 0.05). Multivariable Cox analysis showed that the Ann Arbor stage, maximum standardized uptake value (SUVmax), and RadPFS were independent risk factors associated with PFS. Further, β2-microglobulin, Eastern Cooperative Oncology Group performance status score, SUVmax, and RadOS were independent risk factors for OS. The clinical + metabolic + radiomics model exhibited the greatest discriminative ability for both PFS (Harrell's C-index: 0.805 in the validation cohort) and OS (Harrell's C-index: 0.833 in the validation cohort). The time-dependent ROC analysis indicated that the clinical + metabolic + radiomics model had the best predictive performance. Conclusion: The PET/CT-based clinical + metabolic + radiomics model can enhance prognostication among patients with ENKTCL and may be a non-invasive and efficient risk stratification tool for clinical practice.

• 과학교육연구지
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• 제48권1호
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• pp.1-14
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• 2024

미래세대 과학교육표준(KSES)은 과학적 소양을 과학교육 맥락에서 구현하기 위한 실천 방안으로, 미래사회 및 환경변화에 부응하는 국내 과학교육계획 수립을 지원하기 위하여 개발되었다. 이에 이 연구에서는 KSES와 최근 고시된 2022 개정 중학교 과학과 교육과정의 학습 내용 및 학습 목표의 연관성을 분석하고, 교육과정의 성공적인 현장 안착을 위한 시사점을 얻고자 하였다. 연구 결과, 2022 개정 중학교 과학과 교육과정의 내용 체계는 KSES의 지식 차원과 높은 연관성을 보여주었다. 또한 새롭게 추가된 과학과 사회 영역에서의 내용 요소를 통해 과학의 본성과 관련된 내용을 다루고자 하는 시도도 확인되었다. 성취기준의 경우 KSES의 수행기대 일부 영역에 치중되는 경향을 나타냈으나, 성취기준의 진술 수준은 KSES에서 제시하고 있는 중학교 학생들의 수준에 알맞게 진술되어 있었다. 이러한 결과로부터 2022 개정 과학과 중학교 교육과정과 KSES의 높은 연관성과 함께 미래 과학교육계획 수립을 위한 국제적 지표로서 KSES의 활용가능성을 확인할 수 있었다.