Elongated Lifetime and Enhanced Flux of Hot Electrons on a Perovskite Plasmonic Nanodiode

Park, Yujin,Choi, Jungkweon,Lee, Changhwan,Cho, An-Na,Cho, Dae Won,Park, Nam-Gyu,Ihee, Hyotcherl,Park, Jeong Young American Chemical Society 2019 NANO LETTERS Vol.19 No.8

<P>A fundamental understanding of hot electron transport is critical for developing efficient hot-carrier-based solar cells. There have been significant efforts to enhance hot electron flux, and it has been found that a key factor affecting the hot electron flux is the lifetime of the hot electrons. Here, we report a combined study of hot electron flux and the lifetime of hot carriers using a perovskite-modified plasmonic nanodiode. We found that perovskite deposition on a plasmonic nanodiode can considerably improve hot electron generation induced by photon absorption. The perovskite plasmonic nanodiode consists of MAPbI<SUB>3</SUB> layers covering a plasmonic-Au/TiO<SUB>2</SUB> Schottky junction that is composed of randomly connected Au nanoislands deposited on a TiO<SUB>2</SUB> layer. The measured incident photon-to-electron conversion efficiency and the short-circuit photocurrent show a significantly improved solar-to-electrical conversion performance of this nanodiode. Such an improvement is ascribed to the improved hot electron flux in MAPbI<SUB>3</SUB> caused by effective light absorption from near-field enhancement of plasmonic Au and the efficient capture of hot electrons from Au nanoislands via the formation of a three-dimensional Schottky interface. The relation between the lifetime and flux of hot electrons was confirmed by femtosecond transient absorption spectroscopy that showed considerably longer hot electron lifetimes in MAPbI<SUB>3</SUB> combined with the plasmonic Au structure. These findings can provide a fundamental understanding of hot electron generation and transport in perovskite, which can provide helpful guidance to designing efficient hot carrier photovoltaics.</P> [FIG OMISSION]</BR>

Anti-inflammatory effects of essential oils extracted from Chamaecyparis obtusa on murine models of inflammation and RAW 264.7 cells

PARK, YUJIN,YOO, SEUNG-AH,KIM, WAN-UK,CHO, CHUL-SOO,WOO, JONG-MIN,YOON, CHONG-HYEON Spandidos Publications 2016 MOLECULAR MEDICINE REPORTS Vol. No.

Effectiveness of artificial intelligence robot interventions on psychological health in community-dwelling older adults: A systematic review

Yujin Park,Sun Ju Chang,Hee Jung Kim,Ha Na Jeong 한국노인간호학회 2024 노인간호학회지 Vol.26 No.3

Purpose: The global older adult population is rapidly growing, intensifying the burden of elderly care. To alleviate this challenge of an aging society, interventions utilizing artificial intelligence (AI) technology are becoming widespread. This review aimed to examine the effects of AI robot interventions on the psychological outcomes of community-dwelling older adults through a systematic literature review. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method was employed to identify and select relevant studies. Seven electronic databases were thoroughly searched for eligible studies from June 1st to 30th, 2023. Methodological quality was assessed using RoB 2.0 or RoBANS 2. Results: Thirteen studies (five randomized controlled trials and eight quasi-experimental studies) were selected in the systematic review. Among the selected studies, eight provided AI robot interventions individually, whereas five used a group format, primarily addressing older adults with cognitive impairment or dementia. Depression was the most frequently addressed psychological outcome, with six of ten studies reporting significant effects. Additionally, five studies each highlighted significant effects on emotions, such as positive expressiveness and enjoyment. However, quality of life, anxiety, and loneliness revealed divergent results. Conclusion: AI robots show potential in alleviating psychological challenges for older adults. However, due to the scarcity of high-quality studies, the review recommends conducting more randomized controlled trials with rigorous designs. This review is expected to provide valuable insights for planning and executing AI robot interventions to improve psychological outcomes for community-dwelling older adults in future research.

The role of platelet to lymphocyte ratio and neutrophil to lymphocyte ratio in ulcerative colitis

( Yujin Jeong ),( Seong Ran Jeon ),( Hyun Gun Kim ),( Jung Rock Moon ),( Tae Hee Lee ),( Jae Young Jang ),( Jun-hyung Cho ),( Jun Seok Park ),( Heesu Park ),( Ki-hun Lee ),( Jin-oh Kim ),( Joon Seong 대한장연구학회 2021 Intestinal Research Vol.19 No.1

Background/Aims: Neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) can serve as biomarkers for diagnosing and assessing disease activity in ulcerative colitis (UC). We investigated their clinical significance in UC. Methods: We analyzed 48 patients with UC who underwent measurement of fecal calprotectin (FC) and endoscopy and 96 age- and sex-matched healthy controls. NLR and PLR were compared between the patients and healthy controls. The endoscopic activity was divided into 2 groups: group 1 (mild to moderate inflammation) and group 2 (severe inflammation) according to the Mayo endoscopic subscore in UC. Results: To diagnose UC, the optimal cutoff of NLR and PLR was 2.26 (sensitivity 54.2%; specificity 90.6%; positive likelihood ratio 5.778, 95% confidence interval [CI] 2.944-11.339; area under the curve [AUC] 0.774, 95% CI, 0.690-0.859) and 179.8 (sensitivity 35.4%; specificity 90.6%; positive likelihood ratio 3.778, 95% CI 1.821-7.838; AUC 0.654, 95% CI 0.556-0.753), respectively. The optimal cutoff to differentiate group 1 and group 2 was 3.44, 175.9, and 453 μg/g for NLR, PLR, and FC, respectively (sensitivity, 63.6% vs. 90.9% vs. 81.8%; specificity, 81.1% vs. 78.4% vs. 73.0%; positive likelihood ratio, 3.364 vs. 4.205 vs. 3.027; AUC, 0.714 vs. 0.897 vs. 0.813). PLR had the highest AUC and positive likelihood ratio. Conclusions: NLR and PLR help differentiate patients with UC from healthy controls. NLR, PLR, and FC indicate endoscopic activity and may reflect intestinal mucosal conditions. (Intest Res 2021;19:62-70)

Dysregulation of the Wnt/β-catenin signaling pathway via Rnf146 upregulation in a VPA-induced mouse model of autism spectrum disorder

Park Gaeun,Jang Wooyoung Eric,Kim Seoyeon,Gonzales Edson Luck,Ji Jungeun,Choi Seunghwan,Kim Yujin,Park Ji Hwan,Mohammad Hazara Begum,Bang Geul,Kang Minkyung,Kim Soobin,Jeon Se Jin,Kim Jin Young,Kim Kw 생화학분자생물학회 2023 Experimental and molecular medicine Vol.55 No.-

Autism spectrum disorder (ASD) is a neurodevelopmental disorder associated with impaired social behavior and communication, repetitive behaviors, and restricted interests. In addition to genetic factors, environmental factors such as prenatal drug exposure contribute to the development of ASD. However, how those prenatal factors induce behavioral deficits in the adult stage is not clear. To elucidate ASD pathogenesis at the molecular level, we performed a high-resolution mass spectrometry-based quantitative proteomic analysis on the prefrontal cortex (PFC) of mice exposed to valproic acid (VPA) in utero, a widely used animal model of ASD. Differentially expressed proteins (DEPs) in VPA-exposed mice showed significant overlap with ASD risk genes, including differentially expressed genes from the postmortem cortex of ASD patients. Functional annotations of the DEPs revealed significant enrichment in the Wnt/β-catenin signaling pathway, which is dysregulated by the upregulation of Rnf146 in VPA-exposed mice. Consistently, overexpressing Rnf146 in the PFC impaired social behaviors and altered the Wnt signaling pathway in adult mice. Furthermore, Rnf146-overexpressing PFC neurons showed increased excitatory synaptic transmission, which may underlie impaired social behavior. These results demonstrate that Rnf146 is critical for social behavior and that dysregulation of Rnf146 underlies social deficits in VPA-exposed mice.

Exploring Online Learning Profiles of In-service Teachers in a Professional Development Course

( Yujin Park ),( Jihyun Sung ),( Young Hoan Cho ) 한국교육공학회 2017 Educational Technology International Vol.18 No.2

This study aimed to explore online learning profiles of in-service teachers in South Korea, focusing on video lecture and discussion activities. A total of 269 teachers took an online professional development course for 14 days, using an online learning platform from which web log data were collected. The data showed the frequency of participation and the initial participation time, which was closely related to procrastinating behaviors. A cluster analysis revealed three online learning profiles of in-service teachers: procrastinating (n=42), passive interaction (n=136), and active learning (n=91) clusters. The active learning cluster showed high-level participation in both video lecture and discussion activities from the beginning of the online course, whereas the procrastinating cluster was seldom engaged in learning activities for the first half of the learning period. The passive interaction cluster was actively engaged in watching video lectures from the beginning of the online course but passively participated in discussion activities. As a result, the active learning cluster outperformed the passive interaction cluster in learning achievements. The findings were discussed in regard to how to improve online learning environments through considering online learning profiles of in-service teachers.

PCR amplification and cell-free expression of single-molecule DNA in water-in-oil emulsion droplets

Park YUJIN,Kim DONG-MYUNG 한국생물공학회 2016 한국생물공학회 학술대회 Vol.2016 No.4

Single-molecule PCR amplification and cell-free protein expression in water-in-oil emulsion droplets

Yujin PARK,Dong-Myung KIM 한국생물공학회 2016 한국생물공학회 학술대회 Vol.2016 No.10

Association between Type and Intensity of Physical Activity and Depression

Yujin Chang,Kye-Yeung Park,Hwan-Sik Hwang,Hoon-Ki Park 대한가정의학회 2022 Korean Journal of Family Medicine Vol.43 No.4

Background: Although numerous studies have indicated that lower levels of physical activity correlate with a high-er risk of depression, an association between the type of physical activity and depression has not been identified in Korea. This study aimed to examine whether the type and intensity of physical activity are associated with depres-sion in Korean adults.Methods: This cross-sectional study used data from the Korea National Health and Nutrition Examination Survey (KNHANES). A total of 11,679 individuals were analyzed using multiple logistic regression analyses to identify any association between the type of physical activity and depressive disorders in the sample subjects.Results: Measured weekly in units of energy expenditure, known as metabolic equivalents (METs), the amount of work-related physical activity was higher in individuals with depression according to the Patient Health Question-naire-9 than the participants without depression (386.7 vs. 206.7 MET-min/wk, P=0.01). Those diagnosed with de-pression tended to engage in less recreational activity per week (143.7 vs. 316.3 MET-min/wk, P<0.001) than those without depression. After controlling for covariates, the risk of depression among all participants was 1.012 times higher with a 100-unit increase in total work-related activity measured in METs (95% confidence interval [CI], 1.006–1.017; P<0.001) and 0.962 times lower with a 100-unit increase in total leisure activity measured in METs (95% CI, 0.937–0.987; P=0.003).Conclusion: Different types of physical activity were shown to be differently associated with depressive disorders in Korean adults. This study might guide in reducing work-related physical activity and increasing leisure activity to prevent the occurrence of depression.

Insomnia in North Korean Refugees: Association with Depression and Post-Traumatic Stress Symptoms

YuJin G. Lee,JinYong Jun,YuJin Lee,Juhyun Park,Soohyun Kim,SoHee Lee,SoYoung Yu,SeogJu Kim 대한신경정신의학회 2016 PSYCHIATRY INVESTIGATION Vol.13 No.1

Objective-We investigated the prevalence of insomnia and its clinical characteristics in North Korean refugees. Methods-North Korean refugees living in South Korea (48 males, 129 females; mean age 38.22±12.24 years) and South Koreans (112 males, 203 females; mean age 39.48±10.32 years) completed the following questionnaires: the Self-reported Questionnaire on Insomnia, Center for Epidemiological Studies-Depression Scale (CES-D), Trauma Exposure Check List for North Korean Refugees, and the Impact of Event Scale-Revised (IES-R). Results-North Korean refugees had insomnia more often than South Koreans did (38.42% vs. 8.89%). Depression combined with insomnia was also more prevalent in North Korean refugees (28.25% vs. 3.17%). Compared with South Koreans with insomnia, North Korean refugees with insomnia showed higher CES-D scores. The North Korean refugees with insomnia had experienced a larger number of traumatic events, and had higher CES-D and IES-R scores compared to North Korean refugees without insomnia. Insomnia in North Korean refugees was also associated with the presence of significant depressive and post-traumatic stress disorder (PTSD) symptoms. Conclusion-Insomnia was common in North Korean refugees and was closely associated with depressive and PTSD symptoms. Our study suggests that complaints of insomnia may indicate more severe psychopathology, especially in refugees.