• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.1
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• pp.93-105
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• 2024

Car-sharing is a representative model of the sharing economy, and it is a service that rents or uses a car for the necessary time without owning a car. This industry is growing due to various factors such as technological advances, increasing awareness of environmental protection, and increasing demand for solving traffic congestion problems in cities. Accordingly, there is a need for a strategic approach for companies providing car-sharing services to respond quickly to market changes in order to expand market share and differentiate services. Accordingly, this study conducted a case study on open innovation activities between Gongcar and existing rental car companies, focusing on the research question "What effects do open innovation activities between car-sharing companies and existing rental car companies cause?" As a result of the study, it was confirmed that Gongcar have (1) the ability to actively respond to market fluctuations by establishing a flexible vehicle supply chain based on demand, (2) have significantly reduced growth capital expenditure (Growth Capex), and both cafe and rental car companies have (3) performed successful open innovation by improving key KPI indicators and recording financial performance. This study reveals how open innovation acts as a key business growth engine in the car-sharing industry, and its significance is found in that it empirically confirmed the successful implementation conditions of open innovation based on resource dependence theory.

• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.4274-4281
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• 2023

Blanket is of vital importance for engineering application of the fusion reactor. Nuclear heat deposition in materials is the main heat source in blanket structure. In this paper, the three-dimensional method for thermal-hydraulics/neutronics coupling analysis is developed and applied for the full-scale module of the helium-cooled ceramic breeder tritium breeding blanket (HCCB TBB) designed for China Fusion Engineering Test Reactor (CFETR). The explicit coupling scheme is used to support data transfer for coupling analysis based on cell-to-cell mapping method. The coupling algorithm is realized by the user-defined function compiled in Fluent. The three-dimensional model is established, and then the coupling analysis is performed using the paralleled Coupling Analysis of Thermal-hydraulics and Neutronics Interface Code (CATNIC). The results reveal the relatively small influence of the coupling analysis compared to the traditional method using the radial fitting function of internal heat source. However, the coupling analysis method is quite important considering the nonuniform distribution of the neutron wall loading (NWL) along the poloidal direction. Finally, the structure optimization of the blanket is carried out using the coupling method to satisfy the thermal requirement of all materials. The nonlinear effect between thermal-hydraulics and neutronics is found during the blanket structure optimization, and the tritium production performance is slightly reduced after optimization. Such an adverse effect should be thoroughly evaluated in the future work.

• 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.

• Korean Journal of Environmental Biology
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• v.42 no.2
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• pp.193-206
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• 2024

This study aimed to quantify changes in forest cover and carbon storage of Korean Peninsular during the last two decades by integrating field measurement, satellite remote sensing, and modeling approaches. Our analysis based on 30-m Landsat data revealed that the forested area in Korean Peninsular had diminished significantly by 478,334 ha during the period of 2000-2019, with South Korea and North Korea contributing 51.3% (245,725 ha) and 48.6% (232,610 ha) of the total change, respectively. This comparable pattern of forest loss in both South Korea and North Korea was likely due to reduced forest deforestation and degradation in North Korea and active forest management activity in South Korea. Time series of above ground biomass (AGB) in the Korean Peninsula showed that South and North Korean forests increased their total AGB by 146.4Tg C (AGB at 2020=357.9Tg C) and 140.3Tg C (AGB at 2020=417.4Tg C), respectively, during the last two decades. This could be translated into net AGB increases in South and North Korean forests from 34.8 and 29.4 Mg C ha^-1 C to 58.9(+24.1) and 44.2(+14.8) Mg C ha^-1, respectively. It indicates that South Korean forests are more productive during the study period. Thus, they have sequestered more carbon. Our approaches and results can provide useful information for quantifying national scale forest cover and carbon dynamics. Our results can be utilized for supporting forest restoration planning in North Korea

• International Journal of Stem Cells
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• v.15 no.3
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• pp.311-323
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• 2022

Background and Objectives: Human mesenchymal stem cells (MSCs) are emerging as a treatment for atopic dermatitis (AD), a chronic inflammatory skin disorder that affects a large number of people across the world. Treatment of AD using human umbilical cord blood-derived MSCs (hUCB-MSCs) has recently been studied. However, the mechanism underlying their effect needs to be studied continuously. Thus, the objective of this study was to investigate the immunomodulatory effect of epidermal growth factor (EGF) secreted by hUCB-MSCs on AD. Methods and Results: To explore the mechanism involved in the therapeutic effect of MSCs for AD, a secretome array was performed using culture medium of hUCB-MSCs. Among the list of genes common for epithelium development and skin diseases, we focused on the function of EGF. To elucidate the effect of EGF secreted by hUCB-MSCs, EGF was downregulated in hUCB-MSCs using EGF-targeting small interfering RNA. These cells were then co-cultured with keratinocytes, Th2 cells, and mast cells. Depletion of EGF disrupted immunomodulatory effects of hUCB-MSCs on these AD-related inflammatory cells. In a Dermatophagoides farinae-induced AD mouse model, subcutaneous injection of hUCB-MSCs ameliorated gross scoring, histopathologic damage, and mast cell infiltration. It also significantly reduced levels of inflammatory cytokines including interleukin (IL)-4, tumor necrosis factor (TNF)-α, thymus and activation-regulated chemokine (TARC), and IL-22, as well as IgE levels. These therapeutic effects were significantly attenuated at all evaluation points in mice injected with EGF-depleted hUCB-MSCs. Conclusions: EGF secreted by hUCB-MSCs can improve AD by regulating inflammatory responses of keratinocytes, Th2 cells, and mast cells.

• Journal of Korean society of Dental Hygiene
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• v.24 no.4
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• pp.271-280
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• 2024

Objectives: This study aimed to test whether the digital competence of dental hygienists can affect their intraoral scanning potential in terms of scan time and error. Methods: Dental hygienists and dental hygiene students who had never used an intraoral scanner were surveyed to determine their digital competence. Individual data collected using an intraoral scanner was compared with reference data collected using a model scanner to identify scanning errors, and participants' scanning times were measured. Results: A significant decrease in scanning time was observed as the overall level of digital competence increased. The increase in digital skills and digital knowledge led to a decrease in scanning time by 3.73 and 3.98 minutes, respectively. Conclusions: This study found that digital competence was associated with reduced scan times, but less so with scan errors. This may be due to recent advances in scanning software, and future studies may need to develop a digital competence assessment tool that is more appropriate for the dental field.

• Herbal Formula Science
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• v.32 no.2
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• pp.155-179
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• 2024

Objective : Danggwisu-san (DGSS) is an herbal formula that has been mainly used in the East Asia for the treatment of bruise, sprain and external injury. The cause of this pain is that Qi and blood become tangled and do not circulate well. DGSS can improve the tangled situation and make it well-circulated. The present study evaluated the anti-inflammatory effects of DGSS on Raw 264.7 cells and in rats with paw edema. Methods : Cell viability was measured using the MTT assay. The amount of nitric oxide (NO) production was measured the amount of nitrite content in the cultured medium using Griess reagent. The amount of tumor necrosis factor-α, monocyte chemoattractant protein 1, interleukin (IL)-1βand IL-6 in the cultured supernatant were measured by ELISA kit. Proteins expression were detected by Western blot. Furthermore, the effect of DGSS on acute inflammation was observed in rat paw edema model. Results : The DGSS ameliorates the lipopolysaccharide-activated changes in NO production, iNOS expression and pro-inflammatory cytokines. Additionally, DGSS significantly suppressed expression of p-JNK, p-ERK and nuclear NF-κB. As expected, in rat paw edema study, 1.0 g/kg of DGSS significantly reduced the carrageenan-induced paw edema and iNOS expression for 1-4 h. Moreover, administration of 1.0 g/kg (4 days) of DGSS used in this study did not show any significant change on ALT and AST. Conclusion : These results demonstrate that DGSS has anti-inflammatory effects in vitro and in vivo. Therefore, this present study can put scientific evidences up for the anti-inflammatory effect of DGSS.

• Journal of Nutrition and Health
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• v.57 no.4
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• pp.389-402
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• 2024

Propose: This study examined the antioxidant and anti-gastritis properties of a mixture comprising Ipomoea batatas (IB) extract and Dioscorea japonica (DJ) extract. Methods: The mixture of IB and DJ extracts was analyzed for its total flavonoid content (TFC), total polyphenol content (TPC), and radical scavenging activities. Gastric lesions were induced by treating rats with 1 mL of a solution containing 60% ethanol and 150 mM HCl. The rats were then divided into 5 groups: CON (normal control), HEC (treated with 150 mM HCl-60% ethanol and distilled water), IBE (treated with 150 mM HCl-60% ethanol and IB extract at 350 mg/kg body weight [BW]), ID30 (treated with 150 mM HCl-60% ethanol and a mixture of IB and DJ extracts in a 7:3 ratio at 350 mg/kg BW), and DJE (treated with 150 mM HCl-60% ethanol and DJ extract at 350 mg/kg BW). Results: The ID30 group exhibited significantly higher TFC, TPC, and radical scavenging activities than the groups treated with single extracts. This group also showed a notable decrease in the formation of gastric lesions and preservation of gastric wall mucus. In addition, the serum levels of the inflammatory marker tumor necrosis factor (TNF)-α were significantly lower in the ID30 group than in the HEC group. Conclusion: The antioxidants present in the ID30 mixture effectively reduced oxidative stress and reactive oxygen species, mitigating gastric mucosal irritation induced by alcohol and acid. Furthermore, the mixture inhibited gastric acid secretion and inflammatory marker expression, such as TNF-α, preventing tissue damage. These findings suggest that the ID30 mixture is a potential preventative treatment for gastritis.

• Anatomy and Cell Biology
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• v.57 no.3
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• pp.446-458
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• 2024

The study aims to compare the action of Pleurotus cornucopiae and glibenclamide on alloxan-induced diabetes and ascertain how an aqueous extract of the edible mushroom regulates the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), oxidative stress biomarkers and renal toxicity in a diabetic male Wistar rat model. Twenty-five adult male Wistar rats were randomly grouped into five groups with five rats per. Group 1 and those in the treatment groups received normal feed and water ad libitum. Group 2 received intraperitoneal administration of alloxan monohydrate (150 mg/kg body weight). Group 3 received alloxan monohydrate and glibenclamide (5 mg/kg body weight bwt), group 4 received alloxan monohydrate plus the extract (250 mg/kg bwt) and group 5 received alloxan monohydrate plus the extract (500 mg/kg bwt). The administration of glibenclamide plus the extract was oral for 14 days. Glibenclamide and the extract lowered blood glucose level, catalase, and glutathione peroxidase activities, increased the superoxide dismutase (SOD) activity in rats with alloxan induced diabetes. The extract at 500 mg/kg bwt reduced the plasma urea and sodium concentration in the treated rats. The extract and glibenclamide could detoxify alloxan and restore its induced renal degeneration and glomeruli atrophy, intra renal hemorrhage and inflammation and oxidative biomarkers through activation of Nrf2 expression. The drug glibenclamide and P. cornucopiae have appreciable hypoglycemic activity and potential to restore the normal renal architecture in the rats, hence they offer similar curative effects. Additionally, the extract at 500 mg/kg bwt activated SOD and Nrf2 expression more than glibenclamide in rats with alloxan-induced diabetes.

• Journal of the Korea Society of Computer and Information
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• v.29 no.9
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• pp.179-186
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• 2024

In this paper, we design and implement an Internet of Things (IoT)-based chick incubation system. The system consists of three key components: the IoT incubator, the IoT server system, and the smartphone application. The IoT incubator is composed of an Arduino board, temperature and humidity sensors, a temperature and humidity controller, a ventilation controller, and an egg turning controller. The temperature and humidity sensors measure the temperature and humidity inside the IoT incubator and send the data to the temperature and humidity controller on the Arduino board. Additionally, it provides the function of transmitting temperature, humidity, and control history data to the IoT server via WiFi. It also offers automatic control of ventilation, egg turning, and temperature and humidity on a daily basis. The IoT server system receives data from the incubator, stores it in a database, and provides query data upon request from the smartphone. The smartphone application retrieves historical data through the server and monitors the temperature and humidity data of the IoT incubator in real-time, controlling the IoT incubator to ensure that the set temperature and humidity ranges are maintained. If the temperature and humidity data deviate from the set ranges, it sends alarms and emergency messages to the user. The IoT-based chick incubation system developed in this paper is a low-cost model due to its reduced manufacturing cost, making it highly beneficial for self-sustaining poultry farms.