• Title/Summary/Keyword: study model

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Amelioration of colitis progression by ginseng-derived exosome-like nanoparticles through suppression of inflammatory cytokines

  • Jisu Kim;Shuya Zhang ;Ying Zhu;Ruirui Wang;Jianxin Wang
    • Journal of Ginseng Research
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    • v.47 no.5
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    • pp.627-637
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    • 2023
  • Background: Damage to the healthy intestinal epithelial layer and regulation of the intestinal immune system, closely interrelated, are considered pivotal parts of the curative treatment for inflammatory bowel disease (IBD). Plant-based diets and phytochemicals can support the immune microenvironment in the intestinal epithelial barrier for a balanced immune system by improving the intestinal microecological balance and may have therapeutic potential in colitis. However, there have been only a few reports on the therapeutic potential of plant-derived exosome-like nanoparticles (PENs) and the underlying mechanism in colitis. This study aimed to assess the therapeutic effect of PENs from Panax ginseng, ginseng-derived exosome-like nanoparticles (GENs), in a mouse model of IBD, with a focus on the intestinal immune microenvironment. Method: To evaluate the anti-inflammatory effect of GENs on acute colitis, we treated GENs in Caco2 and lipopolysaccharide (LPS) -induced RAW 264.7 macrophages and analyzed the gene expression of proinflammatory cytokines and anti-inflammatory cytokines such as TNF-α, IL-6, and IL-10 by real-time PCR (RT-PCR). Furthermore, we further examined bacterial DNA from feces and determined the alteration of gut microbiota composition in DSS-induced colitis mice after administration of GENs through 16S rRNA gene sequencing analysis. Result: GENs with low toxicity showed a long-lasting intestinal retention effect for 48 h, which could lead to effective suppression of pro-inflammatory cytokines such as TNF-α and IL-6 production through inhibition of NF-κB in DSS-induced colitis. As a result, it showed longer colon length and suppressed thickening of the colon wall in the mice treated with GENs. Due to the amelioration of the progression of DSS-induced colitis with GENs treatment, the prolonged survival rate was observed for 17 days compared to 9 days in the PBS-treated group. In the gut microbiota analysis, the ratio of Firmicutes/Bacteroidota was decreased, which means GENs have therapeutic effectiveness against IBD. Ingesting GENs would be expected to slow colitis progression, strengthen the gut microbiota, and maintain gut homeostasis by preventing bacterial dysbiosis. Conclusion: GENs have a therapeutic effect on colitis through modulation of the intestinal microbiota and immune microenvironment. GENs not only ameliorate the inflammation in the damaged intestine by downregulating pro-inflammatory cytokines but also help balance the microbiota on the intestinal barrier and thereby improve the digestive system.

Digital Library Interface Research Based on EEG, Eye-Tracking, and Artificial Intelligence Technologies: Focusing on the Utilization of Implicit Relevance Feedback (뇌파, 시선추적 및 인공지능 기술에 기반한 디지털 도서관 인터페이스 연구: 암묵적 적합성 피드백 활용을 중심으로)

  • Hyun-Hee Kim;Yong-Ho Kim
    • Journal of the Korean Society for information Management
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    • v.41 no.1
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    • pp.261-282
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    • 2024
  • This study proposed and evaluated electroencephalography (EEG)-based and eye-tracking-based methods to determine relevance by utilizing users' implicit relevance feedback while navigating content in a digital library. For this, EEG/eye-tracking experiments were conducted on 32 participants using video, image, and text data. To assess the usefulness of the proposed methods, deep learning-based artificial intelligence (AI) techniques were used as a competitive benchmark. The evaluation results showed that EEG component-based methods (av_P600 and f_P3b components) demonstrated high classification accuracy in selecting relevant videos and images (faces/emotions). In contrast, AI-based methods, specifically object recognition and natural language processing, showed high classification accuracy for selecting images (objects) and texts (newspaper articles). Finally, guidelines for implementing a digital library interface based on EEG, eye-tracking, and artificial intelligence technologies have been proposed. Specifically, a system model based on implicit relevance feedback has been presented. Moreover, to enhance classification accuracy, methods suitable for each media type have been suggested, including EEG-based, eye-tracking-based, and AI-based approaches.

Variability of Transrectal Shear Wave Elastography in a Phantom Model (팬텀연구에서 경직장 전단파탄성초음파의 가변성)

  • Jihyun Lee;Seong Kuk Yoon;Jin Han Cho;Hee Jin Kwon;Dong Won Kim;Jun Woo Lee
    • Journal of the Korean Society of Radiology
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    • v.84 no.5
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    • pp.1110-1122
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    • 2023
  • Purpose This study aimed to assess the variability of transrectal shear wave elastography (SWE) using a designed phantom. Materials and Methods In a phantom, the SWE values were examined by two radiologists using agarose and emulsion silicone of different sizes (1, 2, and 3 cm) and shapes (round, cubic) at three depths (1, 2, and 3 cm), two region of interest (ROI) and locations (central, peripheral) using two ultrasound machines (A, B from different vendors). Variability was evaluated using the coefficient of variation (CV). Results The CVs decreased with increasing phantom size. Significant changes in SWE values included; agarose phantom at 3 cm depth (p < 0.001; machine A), 1 cm depth (p = 0.01; machine B), emulsion silicone at 2 cm depth (p = 0.047, p = 0.020; both machines). The CVs increased with increasing depth. Significant changes in SWE values included; 1 cm agarose (p = 0.037, p = 0.021; both machines) and 2 cm agarose phantom (p = 0.047; machine A). Significant differences in SWE values were observed between the shapes for emulsion silicone phantom (p = 0.032; machines A) and between ROI locations on machine B (p ≤ 0.001). The SWE values differed significantly between the two machines (p < 0.05). The intra-/inter-operator agreements were excellent (intraclass correlation coefficient > 0.9). Conclusion The phantom size, depth, and different machines affected the variability of transrectal SWE.

Effect of modifying the thickness of the plate at the level of the overlap length in the presence of bonding defects on the strength of an adhesive joint

  • Attout Boualem;Sidi Mohamed Medjdoub;Madani Kouider;Kaddouri Nadia;Elajrami Mohamed;Belhouari Mohamed;Amin Houari;Salah Amroune;R.D.S.G. Campilho
    • Advances in aircraft and spacecraft science
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    • v.11 no.1
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    • pp.83-103
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    • 2024
  • Adhesive bonding is currently widely used in many industrial fields, particularly in the aeronautics sector. Despite its advantages over mechanical joints such as riveting and welding, adhesive bonding is mostly used for secondary structures due to its low peel strength; especially if it is simultaneously exposed to temperature and humidity; and often presence of bonding defects. In fact, during joint preparation, several types of defects can be introduced into the adhesive layer such as air bubbles, cavities, or cracks, which induce stress concentrations potentially leading to premature failure. Indeed, the presence of defects in the adhesive joint has a significant effect on adhesive stresses, which emphasizes the need for a good surface treatment. The research in this field is aimed at minimizing the stresses in the adhesive joint at its free edges by geometric modifications of the ovelapping part and/or by changing the nature of the substrates. In this study, the finite element method is used to describe the mechanical behavior of bonded joints. Thus, a three-dimensional model is made to analyze the effect of defects in the adhesive joint at areas of high stress concentrations. The analysis consists of estimating the different stresses in an adhesive joint between two 2024-T3 aluminum plates. Two types of single lap joints(SLJ) were analyzed: a standard SLJ and another modified by removing 0.2 mm of material from the thickness of one plate along the overlap length, taking into account several factors such as the applied load, shape, size and position of the defect. The obtained results clearly show that the presence of a bonding defect significantly affects stresses in the adhesive joint, which become important if the joint is subjected to a higher applied load. On the other hand, the geometric modification made to the plate considerably reduces the various stresses in the adhesive joint even in the presence of a bonding defect.

Time-Dependent Warpage Analysis for PCB Considering Viscoelastic Properties of Prepreg (Prepreg의 점탄성 특성을 고려한 PCB의 Time-Dependent Warpage 분석)

  • Chanhee Yang;Chang-Yeon Gu;Min Sang Ju;Junmo Kim;Dong Min Jang;Jae Seok Jang;Jin Woo Jang;Jung Kyu Kim;Taek-Soo Kim
    • Journal of the Microelectronics and Packaging Society
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    • v.31 no.2
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    • pp.23-27
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    • 2024
  • In this study, the time-dependent warpage behavior caused by the viscoelastic properties of prepreg in a printed circuit board (PCB) was analyzed by finite element method (FEM). The accurate viscoelastic properties of the prepreg were measured by stress relaxation test, which were then incorporated into constructed warpage analysis model. When the PCB was subjected to repeated thermal cycles, the warpage of the PCB was restored to its initial state when only the elastic properties of the prepreg were considered, but when the viscoelastic properties were also considered, the warpage was not restored and permanent warpage change occurred. The warpage analysis for three different types of prepreg was conducted to compare their mechanical reliability, and the results showed that materials with elastic properties dominating over viscoelastic properties experienced less warpage, resulting in better mechanical reliability.

Nondestructive Quantification of Corrosion in Cu Interconnects Using Smith Charts (스미스 차트를 이용한 구리 인터커텍트의 비파괴적 부식도 평가)

  • Minkyu Kang;Namgyeong Kim;Hyunwoo Nam;Tae Yeob Kang
    • Journal of the Microelectronics and Packaging Society
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    • v.31 no.2
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    • pp.28-35
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    • 2024
  • Corrosion inside electronic packages significantly impacts the system performance and reliability, necessitating non-destructive diagnostic techniques for system health management. This study aims to present a non-destructive method for assessing corrosion in copper interconnects using the Smith chart, a tool that integrates the magnitude and phase of complex impedance for visualization. For the experiment, specimens simulating copper transmission lines were subjected to temperature and humidity cycles according to the MIL-STD-810G standard to induce corrosion. The corrosion level of the specimen was quantitatively assessed and labeled based on color changes in the R channel. S-parameters and Smith charts with progressing corrosion stages showed unique patterns corresponding to five levels of corrosion, confirming the effectiveness of the Smith chart as a tool for corrosion assessment. Furthermore, by employing data augmentation, 4,444 Smith charts representing various corrosion levels were obtained, and artificial intelligence models were trained to output the corrosion stages of copper interconnects based on the input Smith charts. Among image classification-specialized CNN and Transformer models, the ConvNeXt model achieved the highest diagnostic performance with an accuracy of 89.4%. When diagnosing the corrosion using the Smith chart, it is possible to perform a non-destructive evaluation using electronic signals. Additionally, by integrating and visualizing signal magnitude and phase information, it is expected to perform an intuitive and noise-robust diagnosis.

An identification of determinants to the development of intrapreneurial intention in small & medium sized local hospital in South Korea

  • Chang Hun Lee;Michael G. Hathorn;Doo Young Lee
    • Korea Journal of Hospital Management
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    • v.29 no.2
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    • pp.57-79
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    • 2024
  • Purpose: The present study identified the determinants in the development of intrapreneurial intention in small and medium-sized local hospitals. A careful literature review led to the development of a conceptual model which identified two types of employee competence-individual competence and managerial competence-to influence intrapreneurial orientation positively. It was hypothesized that intrapreneurial orientation predicts intrapreneurial intention and is mediated by intrapreneurial commitment. Methodology/Approach: The target population was chosen from two medical institutions of 'D' Hospital and 'E' Geriatric Hospital in Changwon City, South Korea. Samples were collected from 299 respondents who completed a structured questionnaire. Findings: The results from a structural equation modeling statistical analysis indicated that (1) individual competence and managerial competence positively and significantly predict intrapreneurial orientation, (2) intrapreneurial orientation positively and significantly influences intrapreneurial intention, (3) intrapreneurial commitment partially mediates the relation of intrapreneurial orientation to intrapreneurial intention, and (4) the mediation effect of intrapreneurial commitment was significant in the medical-personnel group, but not in the non-medical group. Practical Implications: Overall findings from the present work provide vital insights into understanding the preconditions for developing employee intrapreneurship in small and medium-sized local hospitals.

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The Herbal Formula C-DM3 Improves the Changes of Diabetes-Related Biomarkers in High-Fat Diet-Induced Obese Mice through Regulation of the IRS1/PI3K/AKT and AMPK Signaling Pathways in the Liver and Pancreas (고지방식이를 통해 비만이 유발된 마우스에서 C-DM3 복합추출물의 항비만 및 항당뇨 효능 연구)

  • Yoon Yong Choi;Chenzi Lyu;Tong Zhang;Haifeng Shao;Xianglong Meng;Chu Duc Thanh;Jong-Seong Kang;Hyo Won Jung;Yong-Ki Park
    • Journal of Korean Medicine for Obesity Research
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    • v.24 no.1
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    • pp.25-40
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    • 2024
  • Objectives: In the present study, we investigated the effects of clean-diabetes mellitus 3 (C-DM3), a herbal formula with Trichosanthis Radix, Coptidis Rhizoma, Crataegi Fructus, and Cinnamomi Cortex, on the pathological and serological symptoms of diabetes and its related molecular mechanisms in diet-induced obese mice. Methods: We prepared an obese mouse model using a high-fat diet for 8 weeks and then administered the C-DM3 extract for 4 weeks. The changes of pathological and serological biomarkers for diabetes assessment were measured in the mice and histological changes were observed in the liver and pancreas tissues. We also identified the main compounds in the C-DM3 extract using high pressure liquid chromatography (HPLC) and analyzed the molecular mechanism of the disease condition by network pharmacological analysis. Results: In the in vivo, the administration of C-DM extract to obese mice significantly reduced body weight gain, fatty liver symptoms, and muscle loss, and decreased the levels of fasting blood glucose, insulin, aspertate aminotransferase, triglycerides, and low-density lipoprotein-cholesterol. In addition, C-DM extract significantly increased the phosphorylation of insulin receptor substrate 1, protein kinase b (AKT), phosphoinositide 3-kinase (PI3K), adenosine monophosphate-activated protein kinase, and glucose transporter 4 in all pancreatic and liver tissues, with inhibition of histopathological changes in obese mice. HPLC analysis identified hyperoside, berberine, epiberberine, columbamin, coptisine, coumarin, jatrorrhizine, and citric acid as the main compounds. In the network pharmacological analysis, the molecular targets of C-DM3 extract on obesity and diabetes were shown as the insulin, AKT, PI3K, and mitogen-activated protein kinase pathways with the regulation of inflammatory molecules interleukin 6 (IL-6), jun proto-oncogene, and IL-1β, which matched our in vivo targets. Conclusions: Based on these results, C-DM3 extract is expected to be effective in improving obesity and preventing diabetic progression.

The Change of Tourism Industry Efficiency in Heilongjiang Province under the Background of Northeast Revitalization Strategy (동북진흥전략 배경하에서 흑룡강성 관광산업의 효율성 변화)

  • Lei Wang;Gi young Chung
    • Industry Promotion Research
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    • v.9 no.3
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    • pp.295-309
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    • 2024
  • With the implementation of the Northeast Revitalization Strategy, the tourism industry in Heilongjiang Province had an increasingly greater impact on regional economic development. Based on the tourism panel data of Heilongjiang Province from 2005 to 2021, this paper used DEA-BCC and Malmquist Index to analyze the static and dynamic changes of the tourism industry.The results of the study were as follows: (1) Static: The OE value reached strong DEA effectiveness in 2010, 2013, and 2019, indicated that tourism resources had been fully utilized. The SE value changed dramatically between 0.354 and 1, and the PTE value approached 1. OE was mainly affected by SE changes. (2) Dynamic: The total factor productivity (TFP) was overall greater than 1 and grew at an average annual rate of 13.8%. The variation in TFP was primarily influenced by the index of technological progress, indicated that the tourism industry in Heilongjiang Province made full use of technology for resource development, with a relatively high level of development efficiency. Therefore, the future focus of Heilongjiang Province's tourism industry will be on adjustments in industrial scale, technological innovation, and policy optimization.

The Effects of Fashion Competence on Social Anxiety in College Students: Focusing on the Mediating Effects of Interpersonal Skills and Appearance Anxiety (대학생의 패션 유능감이 사회불안에 미치는 영향: 대인관계능력과 외모 불안의 매개효과를 중심으로)

  • Li, Aiyou;Lee, Yoon-Jung
    • Journal of Korean Home Economics Education Association
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    • v.35 no.4
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    • pp.99-115
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    • 2023
  • This study aimed to investigate the impact of college students' fashion competence on social anxiety, focusing on the mediating effects of interpersonal skills and appearance anxiety. To this end, a survey was conducted among 235 college students via online communities, and the data were analyzed using SPSS 26.0. The factor analysis revealed sub-factors of fashion competence, including fashion involvement, fashion innovativeness, and confidence in fashion coordination. The regression analysis of the mediation model showed that while fashion involvement indirectly reduces social anxiety through interpersonal skills, there was no mediating effect of appearance anxiety. Fashion innovativeness had an indirect impact on social anxiety through appearance anxiety, but there was no mediating effect through interpersonal skills. Confidence in fashion coordination influenced social anxiety indirectly through both interpersonal skills and appearance anxiety, and it also had a significant direct effect. This research confirmed that fashion competence can have a dual impact on social anxiety, and suggested that enhancing confidence in fashion coordination through fashion therapy programs might be beneficial for resolving college students' social anxiety. However, such programs should avoid excessively pursuing fashion innovativeness, as it can increase appearance anxiety, and should focus on enhancing confidence in one's appearance.