Sun‐Ju Kim, Minjoon Baek, Jinwoo Park, Jae Man Shin
IF 12.1
Small
Structure-shifting polymer particles are of great interest for developing smart soft materials. Here, nanostructured polymer particles capable of switching their morphology in response to external stimuli are presented. The key design is to use a bottlebrush random copolymer with a polydisulfide backbone as a self-assembly building block, in which the polymerization/depolymerization of the dynamic backbone can drive the transformation of the inner particle structure. Nanostructured colloids are generated upon confined assembly of the bottlebrush copolymers in the emulsion droplet, in contrast to the formation of compartmentalized colloids from a blend of polystyrene (PS) and poly(dimethylsiloxane) (PDMS) macromonomers. Exploring the morphology-switching capability reveals that depolymerization of the bottlebrush backbone transforms nanostructured colloids into compartmentalized particles, with intermediate morphologies observed during the depolymerization. Additionally, the morphological transformation is general across multiple inner nanostructures including concentric lamellae, coiled cylinders, and spheres. Importantly, reversible morphology switching capability is realized through polymerization-depolymerization-repolymerization cycles. Finally, the functional potential of these structure-shifting particles is demonstrated by incorporating aggregation-induced emission luminogens (AIEgen). The particles exhibit significant difference in the photoluminescence intensity as a function of particle morphology, attributed to differences in the size of the polymeric domains and the corresponding aggregated state of the luminogens.
Pilot Randomized Clinical Trial of Geriatric Comanagement or Geriatric Guided Supportive Care for Older Patients with Head and Neck CancerReceiving Radiation and Chemotherapy
Kaveh Zakeri, Daphna Y. Gelblum, Armin Shahrokni, Z. Zhang, A. Lopez, Sun‐Ju Kim, Koshy Alexander, Farnia Amirnia, Shuyang Sun, Beatriz Korc‐Grodzicki, N.Y. Lee
IF 6.5
International Journal of Radiation Oncology*Biology*Physics
Tailor‐Made Buffer Materials: Advancing Uniformity and Stability in Perovskite Solar Cells
Thanh–Danh Nguyen, Doyeong Yeo, Ramesh Kumar Chitumalla, Sun‐Ju Kim, G.T. Jeong, Dong‐Gun Kwun, Joonkyung Jang, In Hwan Jung, Ji‐Youn Seo
IF 26
Advanced Energy Materials
Abstract Along with the growing popularity of the p‐i‐n structure, bathocuproine (BCP) is increasingly recognized as a crucial buffer layer between the electron transport layer and electrode with the role of mitigating Schottky contact and enhancing performance. However, the chemical structure and role of its functional groups have not been thoroughly elucidated. This study introduces a novel modification of BCP in perovskite solar cells (PSCs) by altering functional groups to optimize their geometrical molecular structures and electronic properties. The substitution of aromatic phenyl and p‐tolyl groups to 2,9‐position on the BCP is highly effective in increasing the planarity of the conjugated backbone and protecting the reactive nitrogen atoms of the phenanthroline core, thereby improving charge transport and device stability. Experimental analyses, including electrostatic force microscopy, impedance spectroscopy, and photoluminescence, reveal that the modified BCP significantly enhances charge transport, reduces recombination losses, and markedly improves the structural stability of PSCs, leading to prolonged device lifetimes. The findings highlight the potential of structurally optimized BCP derivatives as a critical component in advancing high‐efficiency and durable PSCs.
Sun‐Ju Kim, Minjoon Baek, Jinwoo Park, Jae Man Shin
IF 12.1
Small
Structure-shifting polymer particles are of great interest for developing smart soft materials. Here, nanostructured polymer particles capable of switching their morphology in response to external stimuli are presented. The key design is to use a bottlebrush random copolymer with a polydisulfide backbone as a self-assembly building block, in which the polymerization/depolymerization of the dynamic backbone can drive the transformation of the inner particle structure. Nanostructured colloids are generated upon confined assembly of the bottlebrush copolymers in the emulsion droplet, in contrast to the formation of compartmentalized colloids from a blend of polystyrene (PS) and poly(dimethylsiloxane) (PDMS) macromonomers. Exploring the morphology-switching capability reveals that depolymerization of the bottlebrush backbone transforms nanostructured colloids into compartmentalized particles, with intermediate morphologies observed during the depolymerization. Additionally, the morphological transformation is general across multiple inner nanostructures including concentric lamellae, coiled cylinders, and spheres. Importantly, reversible morphology switching capability is realized through polymerization-depolymerization-repolymerization cycles. Finally, the functional potential of these structure-shifting particles is demonstrated by incorporating aggregation-induced emission luminogens (AIEgen). The particles exhibit significant difference in the photoluminescence intensity as a function of particle morphology, attributed to differences in the size of the polymeric domains and the corresponding aggregated state of the luminogens.
Pilot Randomized Clinical Trial of Geriatric Comanagement or Geriatric Guided Supportive Care for Older Patients with Head and Neck CancerReceiving Radiation and Chemotherapy
Kaveh Zakeri, Daphna Y. Gelblum, Armin Shahrokni, Z. Zhang, A. Lopez, Sun‐Ju Kim, Koshy Alexander, Farnia Amirnia, Shuyang Sun, Beatriz Korc‐Grodzicki, N.Y. Lee
IF 6.5
International Journal of Radiation Oncology*Biology*Physics
Tailor‐Made Buffer Materials: Advancing Uniformity and Stability in Perovskite Solar Cells
Thanh–Danh Nguyen, Doyeong Yeo, Ramesh Kumar Chitumalla, Sun‐Ju Kim, G.T. Jeong, Dong‐Gun Kwun, Joonkyung Jang, In Hwan Jung, Ji‐Youn Seo
IF 26
Advanced Energy Materials
Abstract Along with the growing popularity of the p‐i‐n structure, bathocuproine (BCP) is increasingly recognized as a crucial buffer layer between the electron transport layer and electrode with the role of mitigating Schottky contact and enhancing performance. However, the chemical structure and role of its functional groups have not been thoroughly elucidated. This study introduces a novel modification of BCP in perovskite solar cells (PSCs) by altering functional groups to optimize their geometrical molecular structures and electronic properties. The substitution of aromatic phenyl and p‐tolyl groups to 2,9‐position on the BCP is highly effective in increasing the planarity of the conjugated backbone and protecting the reactive nitrogen atoms of the phenanthroline core, thereby improving charge transport and device stability. Experimental analyses, including electrostatic force microscopy, impedance spectroscopy, and photoluminescence, reveal that the modified BCP significantly enhances charge transport, reduces recombination losses, and markedly improves the structural stability of PSCs, leading to prolonged device lifetimes. The findings highlight the potential of structurally optimized BCP derivatives as a critical component in advancing high‐efficiency and durable PSCs.
High-Fence Type Cultivation Method for Improving Yield of Fresh Goji Berry (Lycium chinense Mill.) Variety ‘Cheonggam’
Hyun-Gu Choi, Hee-Tae Cheong, Seung Wan Son, Bo-Hee Lee, Hyeon Dong Jang, Jeong Hoon Lee, Han Ik Jang, Sun‐Ju Kim, Su Dong Kim, Ju-Yeong Kim, Su-Dong Kim
Korean Journal of Medicinal Crop Science
Background: ‘Cheonggam’ is a high-sugar goji berry (Lycium chinense Mill.) variety developed for fresh consumption; however, its low fruit set and yield limit its commercial use.<br/>Methods and Results: A field experiment was conducted under rain shelter conditions to evaluate the effect of high fence-type training (120 and 150 ㎝ with 90 ㎝ as the control) and different pinching treatments (5 ㎝ twice, 10 ㎝ three times, 20 ㎝ once, and 15 ㎝ twice as the control) on fruit and labor productivity. Compared with the conventional method, high fence-type training at 120 and 150 ㎝ significantly increased the number of fruits per plant (by 1.8 and 2.2-fold, respectively) and fresh fruit yield (by 1.4 and 1.7-fold, respectively). Among the treatments, single pinching at 20 ㎝ was most effective, reducing pinching labor requirements by 50% and increasing yield by 26% compared with the control. In addition, high-fence-type cultivation improved productivity per labor hour in mechanized operations.<br/>Conclusions: These findings suggest that combining high fence-type cultivation with a single 20 ㎝ pinching can significantly enhance both yield and labor efficiency while maintaining fruit quality. These results offer a practical approach to improve the productivity and economic value of ‘Cheonggam’ in fresh goji berry production.
Analysis of the Needs of Liberal Arts Japanese Language Learners and A Case Study: Focusing on Learner-participatory Classes and Classes Taking Personality Types Into Account
Sun‐Ju Kim
The Korean Journal of Japanese Education
본고에서는 교양 일본어 수업을 개선하기 위하여 서울의 S대학교 교양수업인 「일본어1」과 「일본어2」수강생 59명을 대상으로 학습자 참여형 수업 및 성격유형을 고려한 수업방식을 설계하고 실제 교육 현장에 적용한 뒤 실천 사례연구를 수행한 결과를 보고한다. 본 연구 분석 결과, 학습자들은 교양 일본어 수업에서 ‘회화 실습’을 하는 것에 대하여 만족도가 매우 높은 것으로 나타났다.또한 ‘성격유형을 고려한 수업방식’에 대해서는 외향형 학습자보다 내향형 학습자들의 만족도가 높다는 결과가 나타나, 말하기 수업에 있어서 교수자가 내향형 학습자를 배려하여 수업을 설계할 필요가 있다는 사실을 확인할 수 있었다. 특히 내향형 학습자의 비율이 높은 클래스의 경우에 성격 요인을 고려한 교수법을 활용한다면 학습효과 및 학습자 만족도에서 유의미한 효과가 있을 것으로 보인다.본 연구를 통해 학습자 참여형 수업을 성공적으로 수행하기 위해서는 무엇보다 교수자와 학습자 간의 소통이 중요하다는 사실을 확인하였으며, 교수자와 학습자 간의 상호작용 증대를 위해 다양한 교수법을 시도한 본 연구 결과가 교양 일본어 수업, 더 나아가 외국어 말하기 수업 교육 현장에서 활용되기를 기대한다.
Conversion of Polyethylene to Low-Molecular-Weight Oil Products at Moderate Temperatures Using Nickel/Zeolite Nanocatalysts
Hyungjin Cho, Ahyeon Jin, Sun‐Ju Kim, Young-Min Kwon, Eunseo Lee, Jae Man Shin, Byung Hyo Kim
IF 3.2
Materials
Polyethylene (PE) is the most widely used plastic, known for its high mechanical strength and affordability, rendering it responsible for ~70% of packaging waste and contributing to microplastic pollution. The cleavage of the carbon chain can induce the conversion of PE wastes into low-molecular-weight hydrocarbons, such as petroleum oils, waxes, and natural gases, but the thermal degradation of PE is challenging and requires high temperatures exceeding 400 °C due to its lack of specific chemical groups. Herein, we prepare metal/zeolite nanocatalysts by incorporating small-sized nickel nanoparticles into zeolite to lower the degradation temperature of PE. With the use of nanocatalysts, the degradation temperature can be lowered to 350 °C under hydrogen conditions, compared to the 400 °C required for non-catalytic pyrolysis. The metal components of the catalysts facilitate hydrogen adsorption, while the zeolite components stabilize the intermediate radicals or carbocations formed during the degradation process. The successful pyrolysis of PE at low temperatures yields valuable low-molecular-weight oil products, offering a promising pathway for the upcycling of PE into higher value-added products.
Study on Overseas Expansion Strategies for Small and Medium-Sized Korean Construction Companies Using PEST Analysis
Sun‐Ju Kim, Korea Real Estate Industry Society
KOREA REAL ESTATE INDUSTRY SOCIETY
The purpose of this study is to research overseas expansion strategies for small and medium-sized construction companies(SMCCs) in South Korea. The research methodology employs PEST (Political, Economic, Social, and Technological) analysis within the construction industry. Findings suggest increased investment in research and development, adoption of eco-friendly technologies, and localization strategies. By enhancing competitiveness through advanced technology adoption and strengthening sustainable practices aligned with global standards, firms can mitigate political and economic risks. Policy implications include collaboration with government and relevant agencies to support Official Development Assistance (ODA) projects, provide financial assistance, manage risks, and establish integrated information platforms. Moreover, enhancing capabilities through education and consulting programs in technology, law, finance, and risk management prepares firms for international expansion. This study offers specific solutions to Korean small and medium-sized construction companies, emphasizing enhanced policy support to successfully pursue expansion and growth opportunities in the global market.
Comparative Analysis of Blood Transfusion Accuracy and Hemolysis Rate of Transfusion Cartridge Set Between Conventional Infusion Pumps and Cylinder-Type Infusion Pumps
Hee Young Lee, Sun‐Ju Kim, Kang Hyun Lee, Il-Hwan Park, Hyeok-Jin Jeon, Hyun Youk
IF 3.9
Biomedicines
Anyfusion provides an accurate and reliable blood transfusion performance comparable to that of Terufusion, with no significant difference in hemolysis rates; its integration of syringe and infusion methods shows a potential for safer and more efficient transfusion practices, especially in pediatric and emergency settings.
Reprocessible, Reusable, and Self-Healing Polymeric Adsorbent for Removing Perfluorinated Pollutants
Sun‐Ju Kim, Minjoon Baek, Jihye Choe, Jae Man Shin
IF 3.2
Materials
Here, we report a reprocessible, reusable, self-healing, and form-switching polymeric adsorbent for remediating fluorinated pollutants in water. The copolymer hydrogel is designed to contain fluorophilic segments and cationic segments to induce strong binding with perfluorinated pollutants. The sorption performance reveals rapid and quantitative removal of these pollutants, driven by the synergistic effect of fluorophilic and electrostatic interaction. Importantly, a disulfide-containing dynamic crosslinker plays a crucial role in imparting multifunctionality. This enables self-healing by the restoration of crosslinks at the cut surfaces by disulfide exchange reactions and allows for the repeated use of the adsorbent via multiple adsorption-desorption cycles. Furthermore, the adsorbent is reprocessible by cleaving the crosslinks to afford linear copolymers, which can be repolymerized into a hydrogel network on demand. Also, form-switching capability is showcased through the aqueous self-assembly of linear copolymers into a fluorinated micelle, serving as another form of adsorbent for pollutant removal.
The Clinical Usability Evaluation of an Attachable Video Laryngoscope in the Simulated Tracheal Intubation Scenario: A Manikin Study
Wonjun Lee, Hee Young Lee, Sun‐Ju Kim, Kang Hyun Lee
IF 3.7
Bioengineering
The aim of this study was to assess the usefulness of an attachable video laryngoscope (AVL) by attaching a camera and a monitor to a conventional Macintosh laryngoscope (CML). Normal and tongue edema airway scenarios were simulated using a manikin. Twenty physicians performed tracheal intubations using CML, AVL, Pentax Airwayscope<sup>®</sup> (AWS), and McGrath MAC<sup>®</sup> (MAC) in each scenario. Ten physicians who had clinical experience in using tracheal intubation were designated as the skilled group, and another ten physicians who were affiliated with other departments and had little clinical experience using tracheal intubation were designated as the unskilled group. The time required for intubation and the success rate were recorded. The degree of difficulty of use and glottic view assessment were scored by participants. All 20 participants successfully completed the study. There was no difference in tracheal intubation success rate and intubation time in the normal airway scenario in both skilled and unskilled groups. In the experienced group, AWS had the highest success rate (100%) in the tongue edema airway scenario, followed by AVL (60%), MAC (60%), and CML (10%) (<i>p</i> = 0.001). The time required to intubate using AWS was significantly shorter than that with AVL (10.2 s vs. 19.2 s) or MAC (10.2 s vs. 20.4 s, <i>p</i> = 0.007). The difficulty of using AVL was significantly lower than that of CML (7.8 vs. 2.8; <i>p</i> < 0.001). For the experienced group, AVL was interpreted as being inferior to AWS but better than MAC. Similarly, in the unskilled group, AVL had a similar success rate and tracheal intubation time as MAC in the tongue edema scenario, but this was not statistically significant. The difficulty of using AVL was significantly lower than that of CML (8.8 vs. 3.3; <i>p</i> < 0.001). AVL may be an alternative for VL.