• Title/Summary/Keyword: potential model

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Inhibitory Effects of Myagropsis myagroides Ethanol Extract on 2,4-Dinitrochlorobenzene-Induced Atopic Dermatitis-Like Skin Lesions in Mice (2,4-Dinitrochlorobenzene 유도 아토피 피부염 모델 마우스에 대한 외톨개 모자반(Myagropsis myagroides) 에탄올 추출물의 억제 효과)

  • Kim, Koth-Bong-Woo-Ri;Kang, Bo-Kyeong;Ahn, Na-Kyung;Choi, Yeon-Uk;Bae, Nan-Young;Park, Ji-Hye;Park, Sun-Hee;Kim, Min-Ji;Ahn, Dong-Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.8
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    • pp.1121-1127
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    • 2015
  • This study investigated the effects of Myagropsis myagroides ethanol extract (MMEE) on 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD)-like skin lesions in BALB/c mice. The effects of MMEE on DNCB-induced BALB/c mice were evaluated by examining skin symptom severity, levels of total immunoglobulin E (IgE), tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), interleukin (IL)-4, and IL-10 in serum, and levels of IL-4, IL-5, IL-13, and $interferon-{\gamma}$ ($IFN-{\gamma}$) in splenocytes. MMEE significantly reduced the total clinical severity score, total IgE levels, as well as $TNF-{\alpha}$ and IL-4 production in an AD mouse model but increased IL-10 production. Production of IL-4, IL-5, and IL-13 in splenocytes was reduced by MMEE, whereas $IFN-{\gamma}$ production increased. These results suggest that MMEE can inhibit the development of AD-like skin lesions in BALB/c mice by modulating the immune response and may be an effective potential therapeutic agent for AD.

A Study on Characteristics of Lincomycin Degradation by Optimized TiO2/HAP/Ge Composite using Mixture Analysis (혼합물분석을 통해 최적화된 TiO2/HAP/Ge 촉매를 이용한 Lincomycin 제거특성 연구)

  • Kim, Dongwoo;Chang, Soonwoong
    • Journal of the Korean GEO-environmental Society
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    • v.15 no.1
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    • pp.63-68
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    • 2014
  • In this study, it was found that determined the photocatalytic degradation of antibiotics (lincomycin, LM) with various catalyst composite of titanium dioxide ($TiO_2$), hydroxyapatite (HAP) and germanium (Ge) under UV-A irradiation. At first, various type of complex catalysts were investigated to compare the enhanced photocatalytic potential. It was observed that in order to obtain the removal efficiencies were $TiO_2/HAP/Ge$ > $TiO_2/Ge$ > $TiO_2/HAP$. The composition of $TiO_2/HAP/Ge$ using a statistical approach based on mixture analysis design, one of response surface method was investigated. The independent variables of $TiO_2$ ($X_1$), HAP ($X_2$) and Ge ($X_3$) which consisted of 6 condition in each variables was set up to determine the effects on LM ($Y_1$) and TOC ($Y_2$) degradation. Regression analysis on analysis of variance (ANOVA) showed significant p-value (p < 0.05) and high coefficients for determination value ($R^2$ of $Y_1=99.28%$ and $R^2$ of $Y_2=98.91%$). Contour plot and response curve showed that the effects of $TiO_2/HAP/Ge$ composition for LM degradation under UV-A irradiation. And the estimated optimal composition for TOC removal ($Y_2$) were $X_1=0.6913$, $X_2=0.2313$ and $X_3=0.0756$ by coded value. By comparison with actual applications, the experimental results were found to be in good agreement with the model's predictions, with mean results for LM and TOC removal of 99.2% and 49.3%, respectively.

Enhancing Technology Learning Capabilities for Catch-up and Post Catch-up Innovations (기술학습역량 강화를 통한 추격 및 탈추격 혁신 촉진)

  • Bae, Zong-Tae;Lee, Jong-Seon;Koo, Bonjin
    • The Journal of Small Business Innovation
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    • v.19 no.2
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    • pp.53-68
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    • 2016
  • Motivation and activities for technological learning, entrepreneurship, innovation, and creativity are driving forces of economic development in Asian countries. In the early stages of technological development, technological learning and entrepreneurship are efficient ways in which to catch up with advanced countries because firms can accumulate skills and knowledge quickly at relatively low risk. In the later stages of technological development, however, innovation and creativity become more important. This study aims to identify a) the factors (learning capabilities) that influence technological learning performance and b) barriers to enhancing innovation capabilities for the creative economy and organizations. The major part of this study is related to learning capabilities in the post-catch-up era. Based on a literature review and observations from Korean experiences, this study proposes a technological learning model composed of various influencing factors on technological learning. Three hypotheses are derived, and data are collected from Korean machine tool manufacturers. Intense interviews with CEOs and R&D directors are conducted using structured questionnaires. Statistical analysis, such as correlation and ANOVA are then carried out. Furthermore, this study addresses how to enhance innovation capabilities to move forward. Innovation enablers and barriers are identified by case studies and policy analysis. The results of the empirical study identify several levels of firms' learning capabilities and activities such as a) stock of technology, b) potential of technical labor, c) explicit technological efforts, d) readiness to learn, e) top management support, f) a formal technological learning system, g) high learning motivation, h) appropriate technology choice, and i) specific goal setting. These learning capabilities determine firms' learning performance, especially in the early stages of development. Furthermore, it is found that the critical factors for successful technological learning vary along the stages of technology development. Throughout the statistical and policy analyses, this study confirms that technological learning can be understood as an intrinsic principle of the technology development process. Firms perform proactive and creative learning in the late stages, while reactive and imitative learning prevails in the early stages. In addition, this study identifies the driving forces or facilitating factors enhancing innovation performance in the post catch-up era. The results of the preliminary case studies and policy analysis show some facilitating factors such as a) the strategic intent of the CEO and corporate culture, b) leadership and change agents, c) design principles and routines, d) ecosystem and collaboration with partners, and e) intensive R&D investment.

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DEU-7 Derived from Ulmus macrocarpa Improved Immune Functions in Cyclophosphamide-treated Mice (면역억제 마우스 모델에서 왕느릅나무 유래 DEU-7의 면역기능 증강)

  • Kang, Kyung-Hwa;Go, Ji Su;Lee, Inhwan;Lee, Sang Ho;Lee, Sung Do;Kim, Deok Won;Lee, Jong-Hwan;Hwang, HyeJin;Hyun, Sook Kyung;KIM, Byoung Woo;Kim, Chul Min;Chung, Kyung Tae
    • Journal of Life Science
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    • v.25 no.10
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    • pp.1156-1163
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    • 2015
  • The present study investigated the immunomodulatory properties of four different medicinal plants in a cyclophosphamide-treated Balb/c mouse model. One of the four plants, Ulmus macrocarpa, showed partial resistance against immune suppression induced by cyclophosphamide. The bark of U. macrocarpa, commonly known as the Chinese elm, has been used as a pharmaceutical material in Korean traditional medicine to treat bacterial inflammation and induce wound healing. In this study, water extract of U. macrocarpa, named DEU-7, was used for its immunomodulating functional activity. DEU-7 increased the weight of the spleen and the number of splenocytes but did not significantly affect the liver, kidney, and thymus in vivo. A splenocyte viability assay confirmed that DEU-7 influenced ex vivo splenocyte survival. DEU-7 also increased the levels of cytokines, such as IL-2 and IL-4, and immunoglobulins, such as IgM, IgG, and IgA. These results indicated that DEU-7 is involved in the activation of T and B lymphocytes. In addition, DEU-7 was able to maintain the production of cytokines, such as TNF-α, IL-12, and IFN-γ, in the condition of cyclophosphamide-induced immune suppression, suggesting that DEU-7 activated innate immune cells, even under immune suppression. We concluded that DEU-7 aids immunological homeostasis, thereby preventing immune suppression, and aids both innate and adaptive immune response by maintaining the levels of various cytokines and immunoglobulins. Consequently, it is worth investigating the potential of DEU-7 as a supplemental source for immune-enhancing agents.

Recent Trends of Immunologic Studies of Herbal Medicine on Rheumatoid Arthritis (류마티스 관절염에 대한 한약의 면역학적 연구동향)

  • Choi, Do-young;Lee, Jae-dong;Back, Yong-hyeon;Lee, Song-shil;Yoo, Myung-chul;Han, Chung-soo;Yang, Hyung-in;Park, Sang-do;Ryu, Mi-hyun;Park, Eun-kyung;Park, Dong-seok
    • Journal of Acupuncture Research
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    • v.21 no.4
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    • pp.177-196
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    • 2004
  • Objective : Rheumatoid arthritis is an autoimmune disease that pathogenesis is not fully understood and one of the most intractable musculoskeletal diseases. The concern in the immunopathogenesis of rheumatoid arthritis has been increased since 1980's and many immunotherapeutic agents including disease-modifying antirheumatic drugs (DMARDs) were developed and became the mainstay of treatment of rheumatoid arthritis. However, the cure of the disease has hardly been achieved. In oriental medicine, rheumatoid arthritis is related to Bi-Zheng(痺證), that presents pain, swelling, andlor loss of joint function as major clinical manifestations, and also known to be deeply involved in suppression of immune function related to weakness of Jung-Ki(正氣). The herbal medicine, empirically used, could be a potential resource of development of new immunotherapeutic agents for rheumatoid arthritis. Methods : We developed a search strategy using terms to include "rheumatoid arthritis and herbal medicine" combined with "Chinese medicine" and/or "Oriental medicine". The search was focused on experimental studies of herbal medicine (January 1999 to May 2004), which is known to have effects on immune function of patients with rheumatoid arthritis. Computerized search used Internet databases including KISS and RISS4U (Korea), CNKI (China), MOMJ (Main Oriental Medicine Journal, Japan), and PubMed. The articles were selected from journals of universities or major research institutes. Results : The literature search for experimental studies on effects of herbal medicine on immunity of rheumatoid arthritis retrieved a total of 21 articles (Korea; 8, China ; 12, Japan ; 1). Of 21 articles, 10 were related to single-drug formula, 2 to drug interaction, and 9 to multi-drug formula. Single-drug formula was mainly used for aqua-acupuncture and researches on active components. Studies of drug interaction emphasized harmony of Ki-Hyul(氣血) and balance of Han-Yeul(寒熱). Multi-drug regimen was mainly found among formulas for Bo-Ki-Hyul(補氣血) and Bo-Sin(補腎). Conclusion : Studies on rheumatoid arthritis were performed both in vitro and in vivo in vitro study, LPS-stimulated splenocytes and synoviocytes were treated with herbal medicine, resulting in proliferation and activation of immune cells and suppression of cytokine activities in vivo study CIA animal model demonstrated that herbal medicine decreased antibody production and improved function of immune cells. In cellular and molecular study herbal medicine showed profound effects on the level of mRNA expression of certain cytokines related to immune function. This study revealed that herbal medicine has significant immune modulatory action and could be used for recovery of immune dysfunction of rheumatoid arthritis patients.

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The Effects of Endothelin Receptor Antagonist on Hemodynamic and Respiratory Mechanics in Experimental Acute Pulmonary Thromboembolism (실험적 급성 폐색전증에서 Endothelin 수용체 길항제가 혈류 및 호흡 역학에 미치는 영향)

  • Lee, Ji-Hyun;Jeon, Yong-Gam;Choe, Kang-Hyeon;Shim, Tae-Sun;Lim, Chae-Man;Koh, Youn-Suck;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong;Lee, Sang-Do
    • Tuberculosis and Respiratory Diseases
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    • v.48 no.2
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    • pp.210-222
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    • 2000
  • Background: Endothelin(ET) is the most potent vasoconstrictor and bronchoconstrictor. The plasma ET-1 level is elevated in patients with acute pulmonary thromboembolism(APTE). This finding suggest that ET-1 may be an important mediator in the cardiopulmonary derangement of APTE. But whether ET-1 is a pathogenic mediator or a simple marker of APTE is not known. The role of ET-1 in the pathogenesis of cardiopulmonary dysfunction in APTE(delete) was investigated through an evaluation of the effects of $ET_A$-receptor antagonist on APTE. The increase in local levels of preproET-1 mRNA and ET-1 peptide in the embolized lung was also demonstrated. Methods: In a canine autologous blood clot pulmonary embolism model, $ET_A$-receptor antagonist(10 mg/kg intravenously, n=6) was administered one hour after the onset of the embolism. Hemodynamic measurements, blood gas tensions and plasma levels of ET-1 immunoreactivity in this treatment group were compared with those in the control group(n=5). After the experiment., preproET-1 mRNA expression(using Northern blot analysis) and the distribution of ET-1(by immunohistochemical analysis) in the lung tissues were examined. Results: The increases in pulmonary arterial pressure and pulmonary vascular resistance of the treatment group were less than those of the control group. Decrease in cardiac output was also less in the treatment group. Complications such as systemic arterial hypotension and hypoxemia did not occur with the administration of $ET_A$-receptor antagonist The plasma level of ET-1 like(ED: what does 'like' mean?) immunoreactivity was increased after embolization in both groups but was significantly higher in the treatment group. The preproET-1 mRNA and ET-1 peptide expressions were increased in the embolized lung. Conclusion: ET-1 synthesis increases with embolization in the lung and may plays play an important role in the pathophysiology of cardiopulmonary derangement of APTE. Furthermore, $ET_A$-receptor antagonist attenuates cardiopulmonary alterations seen in APTE, suggesting a potential benefit of this therapy.

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The Relationship between Entrepreneurial Education and Entrepreneurial Intentions : Focusing on Moderating Effects of Entrepreneurial Orientation and Environmental Factors (창업교육과 창업의지의 관계: 기업가 지향성과 환경적 요인의 조절효과)

  • Lee, Jae-Seok;Lee, Sang-Myung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.10 no.3
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    • pp.61-74
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    • 2015
  • This study attempts to empirically examine the influence of entrepreneurial education in university on entrepreneurial intentions of undergraduate and graduate students as potential entrepreneur and new moderating factors on the relationship between entrepreneurial education and entrepreneurial intentions. We suggested EO(innovativeness, risk-taking propensity, proactiveness and locus of control) and environmental factors(entrepreneurial family background and resource accessibility) as new moderating factors in the relationship. For this study, the following research questions are raised : First, is there a significant difference in entrepreneurial intentions of enrolled and unenrolled students in entrepreneurial education? Second, does entrepreneurial education affect entrepreneurial intentions positively? Finally, do EO and environmental factors have moderating effects in the relationship between entrepreneurial education and entrepreneurial intentions? In order to test our research model, the current study collected data from 265 undergraduate and graduate students who are majoring in natural sciences or engineering in Seoul National Univ., Hanyang Univ., and KAIST. To investigate our research questions and hypotheses, independent-sample T-test and hierarchical regression analysis were employed. The results of empirical analysis revealed that entrepreneurial education positively related to entrepreneurial intentions and that the relationship between entrepreneurial education and entrepreneurial intentions moderated by EO and environmental factors. First, the result showed the significant difference in entrepreneurial intentions between enrolled and unenrolled students in entrepreneurial education. Entrepreneurial intentions of students who enrolled entrepreneurial education was higher than others. Second, entrepreneurial education affected the entrepreneurial intentions positively. Finally, the moderating effects of innovativeness, risk-taking propensity, proactiveness and entrepreneurial family background among investigated six moderators were significant. entrepreneurial education-entrepreneurial intentions relationship was even stronger under high innovativeness and high proactiveness. But risk-taking propensity and entrepreneurial family background decreased the effect of entrepreneurial education on entrepreneurial intentions.

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Ecological Health Assessments on Turbidwater in the Downstream After a Construction of Yongdam Dam (용담댐 건설후 하류부 하천 생태계의 탁수영향 평가)

  • Kim, Ja-Hyun;Seo, Jin-Won;Na, Young-Eun;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.40 no.1
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    • pp.130-142
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    • 2007
  • This study was to examine impacts of turbid water on fish community in the downstream of Yongdam Dam during the period from June to October 2006. For the research, we selected six sampling sites in the field: two sites were controls with no influences of turbid water from the dam and other remaining four sites were the stations for an assessment of potential turbid effects. We evaluated integrative health conditions throughout applications of various models such as necropsy-based fish health assessment model (FHA), Index of Biological Integrity (IBI) using fish assemblages, and Qualitative Habitat Evaluation Index (QHEI). Laboratory tests on fish exposure under 400 NTU were performed to find out impact of turbid water using scanning electron microscope (SEM). Results showed that fine solid particles were clogging in the gill in the treatments, while particles were not found in the control. This results indicate that when inorganic turbidity increases abruptedly, fish may have a mechanical abrasion or respiratory blocking. The stream health condition, based on the IBI values, ranged between 38 and 48 (average: 42), indicating a "excellent" or "good" condition after the criteria of US EPA (1993). In the mean time, physical habitat condition, based on the QHEI, ranged 97 to 187 (average 154), indicating a "suboptimal condition". These biological outcomes were compared with chemical dataset: IBI values were more correlated (r=0.526, p<0.05, n=18) with QHEI rather than chemical water quality, based on turbidity (r=0.260, p>0.05, n=18). Analysis of the FHA showed that the individual health indicated "excellent condition", while QHEI showed no habitat disturbances (especially bottom substrate and embeddeness), food-web, and spawning place. Consequently, we concluded that the ecological health in downstream of Yongdam Dam was not impacted by the turbid water.

Vitamin D and Risk of Respiratory Tract Infections in Children: A Systematic Review and Meta-analysis of Randomized Controlled Trials (비타민 D와 소아 호흡기 감염의 위험성: 무작위 대조 연구에 대한 체계적 문헌고찰 및 메타분석)

  • Ahn, Jong Gyun;Lee, Dokyung;Kim, Kyung-Hyo
    • Pediatric Infection and Vaccine
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    • v.23 no.2
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    • pp.109-116
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    • 2016
  • Purpose: Recent observational studies have found that vitamin D deficiency is associated with respiratory tract infections. However, randomized controlled trials (RCTs) regarding the efficacy of vitamin D in childhood respiratory tract infection (RTI) have yield inconsistent results. We performed a systematic review and meta-analysis to evaluate the association between vitamin D supplementation and the risk of RTI. Methods: A comprehensive search was conducted using MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trial. Randomized controlled trials of vitamin D supplementation for prevention of RTI in children were included for the analysis. Cochrane Collaboration's tool for assessing the risk of bias was used to assess the quality of the studies. Pooled risk ratios with 95% confidence intervals (CIs) were meta-analyzed using Review Manager 5.3. Results: A total of seven RCTs were included in the meta-analysis. According to a random-effects model, the risk ratio for vitamin D supplementation was 0.82 (95% CI: 0.69-0.98) and $I^2=62%$ for heterogeneity. On subgroup analysis, heterogeneity decreased in the subgroup with follow-up less than 1 year, participants ${\geq}5years$ of age, patients subgroup, and subgroup with dosing daily. Funnel plot showed that there might be publication bias in the field. Conclusions: The present meta-analysis supports a beneficial effect of vitamin D supplementation for the prevention of RTI in children. However, the result should be interpreted with caution due to limitations including a small number of available RCTs, heterogeneity among the studies, and potential publication bias.

A Cohort Study on Risk Factors for Chronic Liver Disease: Analytic Strategies Excluding Potentially Incident Subjects (만성간질환 위험요인에 대한 코호트연구: 잠재적 발병자 집단을 감안한 분석전략)

  • Kim, Dae-Sung;Kim, Dong-Hyun;Bae, Jong-Myun;Shin, Myung-Hee;Ahn, Yoon-Ok;Lee, Moo-Song
    • Journal of Preventive Medicine and Public Health
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    • v.32 no.4
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    • pp.452-458
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    • 1999
  • Objectives: The authors conducted the study to evaluate bias when potentially diseased subjects were included in cohort members while analyzing risk factors of chronic liver diseases. Methods: Total of 14,529 subjects were followed up for the incidence of liver diseases from January 1993 to June 1997. We have used databases of insurance company with medical records, cancer registry, and death certificate data to identify 102 incident cases. The cohort members were classified into potentially diseased group(n=2,217) when they were HBsAg positive, serum GPT levels higher than 40 units, or had or has liver diseases in baseline surveys. Cox's model were used for potentially diseased group, other members, and total subjects, respectively. Results: The risk factors profiles were similar for total and potentially diseased subjects: HBsAg positivity, history of acute liver disease, and recent quittance of smoking or drinking increased the risk. while intake of pork and coffee decreased it. For the potentially diseased, obesity showed marginally significant protective effect. Analysis of subjects excluding the potentially diseased showed distinct profiles: obesity increased the risk, while quitting smoking or drinking had no association. For these intake of raw liver or processed fish or soybean paste stew increased risk; HBsAg positivity, higher levels of liver enzymes and history of acute liver diseases increased the risk. Conclusions: The results suggested the potential bias in risk ratio estimates when potentially diseased subjects were included in cohort study on chronic liver diseases, especially for lifestyles possibly modified after disease onset. The analytic strategy excluding potentially diseased subjects was considered appropriate for identifying risk factors for chronic liver diseases.

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