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18. Pulmonary fibrosis model using micro-CT analyzable human PSC–derived alveolar organoids containing alveolar macrophage-like cells

Author

Choi, Seri, Choi, Jiwoong, Cheon, Seongmin, Song, Jihong, Kim, Seung-Yeon, Kim, Ji-eun, Nam, Dae-Hwan, Manzar, Gohar, Kim, Su-Man, Kang, Hyung-Sik, Kim, Kee K., Jeong, Sang Hoon, Lee, Ju-Han, Park, Eun-Kee, Lee, Minseob, Lee, Hyang-Ae, Kim, Ki-Suk, Park, Han-Jin, Oh, Won Keun, Park, Chungoo, Lee, Chang Hyun, and Kim, Eun-Mi

Published
2022
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22. The utility of intraoperative ultrasonography for spinal cord surgery.

Author

Park, Hangeul, Kim, Jun-Hoe, Lee, Chang-Hyun, Kim, Sum, Kim, Young-Rak, Kim, Kyung-Tae, Kim, Ji-hoon, Rhee, John M., Jo, Woo-Young, Oh, Hyongmin, Park, Hee-Pyoung, and Kim, Chi Heon

Subjects
SPINAL cord surgery, OPERATIVE ultrasonography, DURA mater, BLOOD vessels
Abstract

Objectives: Intraoperative ultrasonography (IOUS) offers the advantage of providing real-time imaging features, yet it is not generally used. This study aims to discuss the benefits of utilizing IOUS in spinal cord surgery and review related literature. Materials and methods: Patients who underwent spinal cord surgery utilizing IOUS at a single institution were retrospectively collected and analyzed to evaluate the benefits derived from the use of IOUS. Results: A total of 43 consecutive patients were analyzed. Schwannoma was the most common tumor (35%), followed by cavernous angioma (23%) and ependymoma (16%). IOUS confirmed tumor extent and location before dura opening in 42 patients (97.7%). It was particularly helpful for myelotomy in deep-seated intramedullary lesions to minimize neural injury in 13 patients (31.0% of 42 patients). IOUS also detected residual or hidden lesions in 3 patients (7.0%) and verified the absence of hematoma post-tumor removal in 23 patients (53.5%). In 3 patients (7.0%), confirming no intradural lesions after removing extradural tumors avoided additional dural incisions. IOUS identified surrounding blood vessels and detected dural defects in one patient (2.3%) respectively. Conclusions: The IOUS can be a valuable tool for spinal cord surgery in identifying the exact location of the pathologic lesions, confirming the completeness of surgery, and minimizing the risk of neural and vascular injury in a real-time fashion. [ABSTRACT FROM AUTHOR]

Published
2024
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26. Trends in degenerative lumbar spinal surgery during the early COVID-19 pandemic in Republic of Korea: A national study utilizing the national health insurance database.

Author

Yuh, Woon Tak, Kim, Jinhee, Kim, Mi-Sook, Kim, Jun-Hoe, Kim, Young Rak, Kim, Sum, Chung, Chun Kee, Lee, Chang-Hyun, Park, Sung Bae, Kim, Kyoung-Tae, Rhee, John M., Ko, Young San, and Kim, Chi Heon

Subjects
COVID-19 pandemic, SPINAL surgery, NATIONAL health insurance, DATABASES, ELECTIVE surgery, HEALTH insurance exchanges, VOLTAGE-controlled oscillators
Abstract

During the first year of the COVID-19 pandemic, the Republic of Korea (ROK) experienced three epidemic waves in February, August, and November 2020. These waves, combined with the overarching pandemic, significantly influenced trends in spinal surgery. This study aimed to investigate the trends in degenerative lumbar spinal surgery in ROK during the early COVID-19 pandemic, especially in relation to specific epidemic waves. Using the National Health Information Database in ROK, we identified all patients who underwent surgery for degenerative lumbar spinal diseases between January 1, 2019 and December 31, 2020. A joinpoint regression was used to assess temporal trends in spinal surgeries over the first year of the COVID-19 pandemic. The number of surgeries decreased following the first and second epidemic waves (p<0.01 and p = 0.34, respectively), but these were offset by compensatory increases later on (p<0.01 and p = 0.05, respectively). However, the third epidemic wave did not lead to a decrease in surgical volume, and the total number of surgeries remained comparable to the period before the pandemic. When compared to the pre-COVID-19 period, average LOH was reduced by 1 day during the COVID-19 period (p<0.01), while mean hospital costs increased significantly from 3,511 to 4,061 USD (p<0.01). Additionally, the transfer rate and the 30-day readmission rate significantly decreased (both p<0.01), while the reoperation rate remained stable (p = 0.36). Despite the impact of epidemic waves on monthly surgery numbers, a subsequent compensatory increase was observed, indicating that surgical care has adapted to the challenges of the pandemic. This adaptability, along with the stable total number of operations, highlights the potential for healthcare systems to continue elective spine surgery during public health crises with strategic resource allocation and patient triage. Policies should ensure that surgeries for degenerative spinal diseases, particularly those not requiring urgent care but crucial for patient quality of life, are not unnecessarily halted. [ABSTRACT FROM AUTHOR]

Published
2024
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35. Latent traits of lung tissue patterns in former smokers derived by dual channel deep learning in computed tomography images

Author

Li, Frank, Choi, Jiwoong, Zou, Chunrui, Newell, Jr., John D., Comellas, Alejandro P., Lee, Chang Hyun, Ko, Hongseok, Barr, R. Graham, Bleecker, Eugene R., Cooper, Christopher B., Abtin, Fereidoun, Barjaktarevic, Igor, Couper, David, Han, MeiLan, Hansel, Nadia N., Kanner, Richard E., Paine, III, Robert, Kazerooni, Ella A., Martinez, Fernando J., O’Neal, Wanda, Rennard, Stephen I., Smith, Benjamin M., Woodruff, Prescott G., Hoffman, Eric A., and Lin, Ching-Long

Published
2021
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47. Development of real-time onion disease monitoring system using image acquisition

Author

Du-Han KIM, Kyeong-Hwan LEE, Chang-Hyun CHOI, Tae-Hyun CHOI, Yong-Joo KIM

Subjects
imaging acquisition system, disease, downy mildew, onion, Agriculture (General), S1-972
Abstract

In this study, real-time disease monitoring was conducted on onion which is the most representative crop in Republic of Korea, using an image acquisition system newly developed for the mobile measurement of phenotype. The purpose of this study was to improve the accuracy of prediction of disease and state variables by processing images acquired from monitoring. The image acquisition system was consisted of two parts, a motorized driving system and a PTZ (pan, tilt and zoom) camera to take images of the plants. The acquired images were processed as follows. Noise was removed through an image filter and RGB (red, green and blue) colors were converted to HSV (hue, saturation and value), which enabled thresholding of areas with different colors and properties for image binarization by comparing the color of onion leaf with ambient areas. Four objects with the most significant browning in the onion leaf to the naked eye were selected as the samples for data acquired. The thresholding method with image processing was found to be superior to the naked eye in identifying accurate disease areas. In addition, it was found that the incidence of disease was different in each disease area ratio. As a result, the use of image acquisition system in image processing analysis will enable more prompt detection of any changes in the onion and monitoring of disease outbreaks during the crop lifecycle.

Published
2018
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49. The knowledge base for physical education teacher education (PETE) : a comparative study of university programmes in England and Korea

Author

Lee, Chang-Hyun

Subjects
613.7071, X300 Academic studies in Education, physical education, Korea
Abstract

This study compares and explains the knowledge base (Kirk et al, 1997; Shulman, 1987) for teaching physical education in Physical Education Teacher Education (PETE) programmes in England and Korea from the 1960s to the present. In the USA (Siedentop, 1989), the UK (Kirk, 1992) and Australia (Macdonald et al, 1999), the erosion of time spent on content knowledge (CK) for sports and other physical activities has been noted as a matter of concern. The academicisation of the physical activity field and the marginalisation of PETE within it are major factors in the shift in the knowledge base. Data was presented from a comparative study of four PETE programme in two countries in respect of social constructionism (Berger and Luckmann, 1966). The historical resources such as timetables, curricula and official documents were analysed using documentary methods and grounded theory. Grounded theory was also used to analyse interviews with previous and present teacher educators, student teachers, and teachers who graduated from each university. I found that for universities in both countries, first, the hours of theoretical content knowledge (TCK) and practical content knowledge (PRACK) in PETE had been reduced over time. Time for units of physical activity had decreased significantly. Second, student teachers learnt physical activity to introductory levels only, and the spiral system for the physical activity curriculum, where students ideally move from introductory to advanced levels of knowledge, did not work well. In terms of differences between the countries, first, in England there were many sessions where PRACK was interrelated with pedagogical content knowledge (PCK) and knowledge of learners and their characteristics (KLC). However, this was less common in Korea. In particular, interrelationships between PRACK and PCK and KLC were very weak because the Korean system is based on the study of kinesiology. Second, many students and teachers in England requested sessions to assist them to teach at GCSE and A Level. In Korea, in contrast, the need for PCK and KLC was identified. I conclude by confirming that CK forms only a small proportion of the knowledge base for teaching physical education confirming that there is a gap between the knowledge base in PETE and the knowledge requirements for teaching physical education in schools. I suggest developing special units in the PETE course based on models of learning, teaching and philosophy and being suitable for inclusion in the academic and scholarly culture of the university.

Published
2013

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