Preoperative Cardiac Computed Tomography Characteristics Associated with Recurrent Aortic Regurgitation after Aortic Valve Re-Implantation

안유라,구현정,이사민,김대희,송종민,강덕현,송재관,김호진,김준범,정성호,추석정,정철현,이재원,강준원,양동현 대한영상의학회 2020 Korean Journal of Radiology Vol.21 No.2

Objective: To identify the preoperative cardiac computed tomography (CT) factors influencing postoperative recurrent aortic regurgitation (AR) in patients who underwent aortic valve repair with the re-implantation technique (David operation) due to AR. Materials and Methods: A total of 117 patients (age, 49.4 ± 15.6 years; 83 males) who underwent the David operation for AR were included in this retrospective study. Aortic root profiles including the aortic regurgitant orifice area (ARO) and the aortic cusp asymmetry ratio of the areas (ASRarea), which is defined as the maximum/minimum areas among the three cusp areas at the level of the commissures, were measured on preoperative cardiac CT scans. Clinical and CT findings were compared between a group with recurrent AR grade < 3 (no, trivial, or mild AR) and recurrent ≥ 3 + AR. To determine the optimal cut-off values of ASR and ARO, the receiver operating characteristic (ROC) curve was used. Cox regression analysis was used for the analysis of the factors affecting recurrent 3 + AR. Results: Postoperatively, recurrent 3 + AR developed in 17 (14.5%) patients and occurred within a median of 268 days (interquartile range: 78–582 days). The cut-off ARO value for discriminating the patients with recurrent 3 + AR was > 24 mm2 (sensitivity, 76.5%; specificity 64.8%), and the area under the ROC curve (AUC) was 0.72. For ASRarea, the cut-off value was > 1.58 (sensitivity, 76.5%; specificity, 58.0%) and the AUC was 0.64. Multivariable Cox regression showed that ARO > 24 mm2 (hazard ratio = 3.79, p = 0.020) was a potential independent parameter for recurrent 3 + AR. ROC for the linear regression model showed that the AUC for both ARO and ASRarea was 0.73 (95% confidence interval, 0.64–0.81, p < 0.001). Conclusion: ARO and ASRarea detected on preoperative cardiac CT would be potentially helpful for identifying AR patients who may benefit from the David operation.

Development and Validation of a Simple Index Based on Non-Enhanced CT and Clinical Factors for Prediction of Non-Alcoholic Fatty Liver Disease

안유라,윤성철,이승수,손정희,조소라,변지은,성유섭,김호성,유은실 대한영상의학회 2020 Korean Journal of Radiology Vol.21 No.4

Objective: A widely applicable, non-invasive screening method for non-alcoholic fatty liver disease (NAFLD) is needed. We aimed to develop and validate an index combining computed tomography (CT) and routine clinical data for screening for NAFLD in a large cohort of adults with pathologically proven NAFLD. Materials and Methods: This retrospective study included 2218 living liver donors who had undergone liver biopsy and CT within a span of 3 days. Donors were randomized 2:1 into development and test cohorts. CTL-S was measured by subtracting splenic attenuation from hepatic attenuation on non-enhanced CT. Multivariable logistic regression analysis of the development cohort was utilized to develop a clinical-CT index predicting pathologically proven NAFLD. The diagnostic performance was evaluated by analyzing the areas under the receiver operating characteristic curve (AUC). The cutoffs for the clinical-CT index were determined for 90% sensitivity and 90% specificity in the development cohort, and their diagnostic performance was evaluated in the test cohort. Results: The clinical-CT index included CTL-S, body mass index, and aspartate transaminase and triglyceride concentrations. In the test cohort, the clinical-CT index (AUC, 0.81) outperformed CTL-S (0.74; p < 0.001) and clinical indices (0.73–0.75; p < 0.001) in diagnosing NAFLD. A cutoff of ≥ 46 had a sensitivity of 89% and a specificity of 41%, whereas a cutoff of ≥ 56.5 had a sensitivity of 57% and a specificity of 89%. Conclusion: The clinical-CT index is more accurate than CTL-S and clinical indices alone for the diagnosis of NAFLD and may be clinically useful in screening for NAFLD.

원자모형에 기초한 예비과학교사들의 과학의 본성에 대한 인식

안유라 ( Yu La An ),김현주 ( Hyun Joo Kim ) 한국과학교육학회 2011 한국과학교육학회지 Vol.31 No.4

이 연구는 원자모형 사례를 이용한 과학의 본성 검사지를 사용하여 중등예비 과학교사들이 가지고 있는 과학의 본성에 대한 인식이 ``원자모형``이라는 과학지식과 관련되어 어떻게 드러나는지를 살펴보고, 기존의 선행연구와 비교해 보았다. ``모형에 관한 인식``, ``과학지식의 잠정성``, ``과학에서의 주관성``, ``추론과 상상력의 사용``, ``보편적인 과학적 방법에 대한 잘못된 신념``, ``과학과 예술의 비교``라는 6 관점을 조사하였다. 연구결과, 예비과학교사들은 과학지식(구름원자모형)의 잠정성, 과학에서의 주관성(톰슨과 러더퍼드의 알파입자 산란실험에 대한 해석)에 대해 비교적 잘 이해하고 있는 것으로 나타난 반면, 보편적인 과학적 방법과 관련하여 가장 바람직하지 못한 인식을 드러냈다. 모형(원자모형)에 관한 인식과 과학(보어의 원자모형)과 예술(피카소의 작품)을 비교하는 영역에서는 존재론적 관점과 구성주의적 관점이 혼재되어 나타났으며, 과학연구에서 상상력의 사용은 필수적인 동시에 최대한 자제되어야 한다는 다소 모순된 생각을 보여줬다. ``모형``이나 ``과학이론``과 같은 일반적인 용어를 사용하여 조사된 기존의 선행연구들을 본 연구결과와 비교한 결과, 과학지식의 잠정성에 대해 보다 높은 긍정을 나타내게 했으며, 과학자의 연구방법에 대해 구체적인 과학자를 제시하였을 때, 응답자들은 좀 더 바람직한 인식을 드러내는 경향을 보였다. The purpose of this study was to examine preservice secondary science teachers` understanding of the nature of science, by using nature of science (NOS) questionnaire on the basis of atomic model, and compare this to pre-studies. ``Understanding of nature of scientific model,`` ``Tentativeness of scientific knowledge,`` ``Subjectivity in science,`` ``Use of inference and imagination,`` ``Myths of the scientific method,`` and ``Comparison between science and art.`` were examined. Preservice teachers showed great comprehension of the tentativeness of scientific knowledge (the orbital model) and the subjectivity in science (the different interpretation about the experiment of particle scattering), but displayed the lowest comprehension of the scientific method. For understanding of nature of scientific model (the atomic model) and the comparison between science (Bohr`s atomic model) and art (Picasso`s work), preservice teachers brought out a combination of ontological and constructivist perspective and showed the contradictory thought about imagination in science research. In the result of comparison to pre-studies using the NOS instruments contains general terms, represented high levels of agreement about the tentativeness of scientific knowledge by using concrete examples of ``atomic model``. When concrete scientists such as Thomson, Rutherford, Bohr were presented, respondents revealed more informed views about the scientists` research method.

인공지능기반 스마트 온실 데이터 수집 가이드라인 설계

서정훈(Seo Jeong Hun),안유라(An Yu Ra),이명훈(Lee Meong Hun),여현(Yoe Hyun) 한국통신학회 2023 한국통신학회 학술대회논문집 Vol.2023 No.2

Computer-Aided Diagnosis System for the Evaluation of Thyroid Nodules on Ultrasonography: Prospective Non-Inferiority Study according to the Experience Level of Radiologists

정새롬,백정환,이민경,안유라,Young Jun Choi,성태연,송동은,김태용,이정현 대한영상의학회 2020 Korean Journal of Radiology Vol.21 No.3

Objective: To determine whether a computer-aided diagnosis (CAD) system for the evaluation of thyroid nodules is non-inferior to radiologists with different levels of experience. Materials and Methods: Patients with thyroid nodules with a decisive diagnosis of benign or malignant nodule were consecutively enrolled from November 2017 to September 2018. Three radiologists with different levels of experience (1 month, 4 years, and 7 years) in thyroid ultrasound (US) reviewed the thyroid US with and without using the CAD system. Statistical analyses included non-inferiority testing of the diagnostic accuracy for malignant thyroid nodules between the CAD system and the three radiologists with a non-inferiority margin of 10%, comparison of the diagnostic performance, and the added value of the CAD system to the radiologists. Results: Altogether, 197 patients were included in the study cohort. The diagnostic accuracy of the CAD system (88.5%, 95% confidence interval [CI] = 82.7–92.5) was non-inferior to that of the radiologists with less experience (1 month and 4 year) of thyroid US (83.0%, 95% CI = 76.5–88.0; p < 0.001), whereas it was inferior to that of the experienced radiologist (7 years) (95.8%, 95% CI = 91.4–98.0; p = 0.138). The sensitivity and negative predictive value of the CAD system were significantly higher than those of the less-experienced radiologists were, whereas no significant difference was found with those of the experienced radiologist. A combination of US and the CAD system significantly improved sensitivity and negative predictive value, although the specificity and positive predictive value deteriorated for the less-experienced radiologists. Conclusion: The CAD system may offer support for decision-making in the diagnosis of malignant thyroid nodules for operators who have less experience with thyroid US.

MQTT, ESP-NOW 통신 기반 스마트팜 네트워크 시스템 설계

임상민(Lim Sang Min),여현(Yoe Hyun),안유라(An Yu Ra),정주원(Jeong Joo Won),이명훈(Lee Meong Hun) 한국통신학회 2023 한국통신학회 학술대회논문집 Vol.2023 No.2

스마트 축사의 센서 고장 예측을 위한 통합 플랫폼 설계

양광호(Yang Kwang Ho),여현(Yoe Hyun),안유라(An Yu Ra),이명훈(Lee Meong Hun) 한국통신학회 2023 한국통신학회 학술대회논문집 Vol.2023 No.6

과학자의 연구과정을 가시화한 학습 프로그램이 고등학교 1학년 학생들의 진로지향에 미치는 영향

신호심,정애진,장은경,김명희,김연숙,안유라,강성주,이길재,김현주 한국교원대학교 교육연구원 2010 敎員敎育 Vol.26 No.2

The purpose of this study was to investigate the effects of the learning programs visualizing the scientists’ research process on the career orientation of 10th grade high school students. After our developing the learning program reflected each research type such as the problem-solving type, the modeling type, and the idea-creative type, this program was applied to 30 high school students who have not decided their future career. Before starting this program, students took science career orientation questionnaire. After ending this program, we investigated science career orientation questionnaire again and conducted the descriptive questionnaires for the program. The result shows that this program got affirmative effect on students' career choices. To the science career-oriented students, this program made their career-orientation be more solid. Also it made some of the non-science career-oriented students change the career-orientation to the science and some of them had in mind to change their orientation to the science career. Like this, this program played no small part in the non-science career -orientated students. Therefore it means that the program could be applicable in the science career education. 본 연구에서는 과학자의 연구과정이 가시화된 학습 프로그램이 일반계 고등학교 1학년 학생들의 진로에 미치는 영향을 알아보고자 하였다. 과학자의 연구형태 중 문제해결형, 모델제시형, 아이디어산출형의 연구과정을 적용하여 개발된 학습 프로그램을 아직 진로가 확정적이지 않은 일반계 고등학교 1학년 30명에게 적용하였다. 사전사후에 진로지향을 조사하였고, 프로그램이 진로에 미친 영향을 구체적으로 기술하게 하기 위하여 설문조사를 실시하였다. 그 결과, 본 프로그램은 학생들의 진로 결정에 전반적으로 긍정적인 영향을 주었음이 확인되었고, 진로지향의 변화에 따른 분석에서 본 프로그램은 학생들의 과학진로를 더 확고하게 하는 등 이미 과학진로지향인 학생들에게 긍정적인 영향을 주었음이 확인되었다. 또한 과학진로지향이 아닌 학생들 중 일부는 프로그램의 적용 후에 과학관련 분야로 진로를 바꾸었고, 일부는 과학관련 분야로 진로를 바꾸고 싶은 마음이 생기는 등 본 프로그램이 과학진로지향이 아닌 학생들에게 미친 영향도 적지 않음을 확인하였다. 이는 본 프로그램이 과학진로교육에 활용될 수 있는 가능성을 보여준다.