• Journal of Korea Trade
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• v.25 no.4
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• pp.108-127
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• 2021

Purpose - On the basis of knowledge transfer theory, we empirically explored how three types of human resource (HR) innovation knowledge exchange within a Chaebol drive the global subsidiary performance of the headquarters (HQ) of a Chaebol's globally affiliated companies. Design/methodology - Using a sample of 176 Korean HQ firms of the top 53 Chaebols and 1,061 of their foreign manufacturing subsidiaries (n = 1,061), we tested the relationship between the exchange of explorative and exploitative sustainable HR innovation knowledge among HQ firms of Chaebols, their subsequent transfer of technical HR knowledge via technical schemas, and the subsequent impact on the global subsidiary performance. Findings - The Chaebols' decisions about the three strategic knowledge management options (i.e., the degree of exchange of explorative and exploitative technological HR innovation knowledge and the extent of HQ-subsidiary HR knowledge transfer) have highly significant relationships with the global subsidiary performance. The results help explains the conditions under which the explorative versus exchange of exploitative sustainable HR innovation knowledge pays off by showing the moderating role of the degree of HQ-to-subsidiary technical HR knowledge transfer, at least in the case of the Chaebol as one representative type of the emerging-market business groups. Originality/value - As the first of its kind in the field of sustainable HR innovation knowledge management at the business group level, the present study makes a clear contribution in demonstrating how the performance of Chaebols' manufacturing subsidiaries depends greatly on their strategy for management of knowledge, as reflected in the choices they make about sharing both explorative and exploitative sustainable HR innovation knowledge among HQ firms and the subsequent transfer of HQ's sustainable HR innovation knowledge to the foreign subsidiaries.

• Structural Engineering and Mechanics
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• v.85 no.2
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• pp.275-287
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• 2023

The use of environmental-friendly building materials is becoming increasingly popular worldwide. Compared to the normal concrete, rubber-based concrete is considered more durable, environmentally friendly, socially and economically viable. In this investigation, M20 grade concrete was designed and the fine aggregates were replaced with crumb rubber of two different micron sizes (0.221 mm and 0.350 mm). Fly ash (FA) and silica fume (SF) replaces the binder as supplementary cementitious materials at a rate of 0, 5, 10, 15, and 20% by weight. The mechanical properties of concrete including compressive strength, tensile, and flexural strength were determined. The polynomial work expectation validates the response surface approach (RSM) concept for optimizing SF and FA substitution. The maximum compressive strength (22.53 MPa) can be observed for the concrete containing 10% crumb rubber, 15% fly ash and 15% silica fume. The reduced unit weight of the rubberized concrete may be attributed to the lower specific gravity of the rubber particles. Two-way ANOVA with a significance criterion of less than 0.001 has been utilized with modest residual error from the lack of fit and the pure error. The predictive model accurately forecasts the variable-response relationship. Since, the crumb rubber is obtained from wasted tires incorporating FA and SF as a cementitious ingredient, it helps to significantly improve mechanical properties of concrete and reduce environmental degradation.

• Journal of Ginseng Research
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• v.47 no.2
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• pp.311-318
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• 2023

Background: The beneficial effects of compound K (CK) on different chronic diseases have been shown to be at least related to antioxidant action. Nevertheless, since its antioxidant activity in human retinal pigment epithelial (RPE) cells is still unknown, here we investigated whether CK alleviates oxidative stress-stimulated damage in RPE ARPE-19 cells. Methods: The cytoprotective consequence of CK in hydrogen peroxide (H₂O₂)-treated cells was evaluated by cell viability, DNA damage, and apoptosis assays. Fluorescence analysis and immunoblotting were performed to investigate the inhibitory action of CK on reactive oxygen species (ROS) production and mitochondrial dysfunction. Results: H₂O₂-promoted cytotoxicity, oxidative stress, DNA damage, mitochondrial impairment, and apoptosis were significantly attenuated by CK in ARPE-19 cells. Furthermore, nuclear factor erythroid 2-related factor 2 (Nrf2) phosphorylation level and its shuttling to the nucleus were increased, which was correlated with upregulated activation of heme oxygenase-1 (HO-1). However, zinc protoporphyrin, a blocker of HO-1, significantly abrogated the preventive action of CK in H₂O₂-treated ARPE-19 cells. Conclusion: This study indicates that activation of Nrf2/HO-1 signaling by CK plays an important role in rescuing ARPE-19 cells from oxidative cellular damage.

• Steel and Composite Structures
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• v.48 no.1
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• pp.1-17
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• 2023

The main goal of this paper is to study vibration of damaged core laminated sectorial plates with Functionally graded (FG) face sheets based on three-dimensional theory of elasticity. The structures are made of a damaged isotropic core and two external face sheets. These skins are strengthened at the nanoscale level by randomly oriented Carbon nanotubes (CNTs) and are reinforced at the microscale stage by oriented straight fibers. These reinforcing phases are included in a polymer matrix and a three-phase approach based on the Eshelby-Mori-Tanaka scheme and on the Halpin-Tsai approach, which is developed to compute the overall mechanical properties of the composite material. Three complicated equations of motion for the sectorial plates under consideration are semi-analytically solved by using 2-D differential quadrature method. Using the 2-D differential quadrature method in the r- and z-directions, allows one to deal with sandwich annular sector plate with arbitrary thickness distribution of material properties and also to implement the effects of different boundary conditions of the structure efficiently and in an exact manner. The fast rate of convergence and accuracy of the method are investigated through the different solved examples. The sandwich annular sector plate is assumed to be simply supported in the radial edges while any arbitrary boundary conditions are applied to the other two circular edges including simply supported, clamped and free. Several parametric analyses are carried out to investigate the mechanical behavior of these multi-layered structures depending on the damage features, through-the-thickness distribution and boundary conditions.

• Journal of Korean Neurosurgical Society
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• v.66 no.6
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• pp.735-742
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• 2023

Nephrotic syndrome (NS) is associated with cerebral venous sinus thrombosis (CVST), which is a rare cerebrovascular disorder in children. Systemic anticoagulation with heparin is the standard therapy for CVST, and mechanical thrombectomy (MT) has been described as a salvage treatment for adult anticoagulant refractory CVST, However, it has never been reported in children. We describe a case of MT for refractory CVST in a child with NS. A 13-year-old boy with newly diagnosed NS presented to an emergency department with acute headache. A head computed tomography showed acute thrombus in the superior sagittal sinus, straight sinus and transverse sinus. The child was started on heparin therapy, but clinically deteriorated and became unresponsive. In view of the rapid deterioration of the condition after anticoagulation treatment, the patient received intravascular treatment. Several endovascular technologies, such as stent retriever and large bore suction catheter have been adopted. After endovascular treatment, the patient's neurological condition was improved within 24 hours, and magnetic resonance venography of the head demonstrated that the CVST was reduced. The child recovered with normal neurological function at discharge. This case highlights the importance of considering MT for refractory CVST, and we suggest that MT may be considered for refractory CVST with NS in children.

• Nuclear Engineering and Technology
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• v.56 no.1
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• pp.78-91
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• 2024

Double steel plate concrete composite shear wall (SCSW) has been widely utilized in nuclear power plants and high-rise structures, and its shear connectors have a substantial impact on the seismic performance of SCSW. Therefore, in this study, the mechanical properties of SCSW with angle stiffening ribs as shear connections were parametrically examined for the reactor containment structure of nuclear power plants. The axial compression ratio of the SCSW, the spacing of the angle stiffening rib arrangement and the thickness of the angle stiffening rib steel plate were selected as the study parameters. Four finite element models were constructed by using the finite element program named ABAQUS to verify the experimental results of our team, and 13 finite element models were established to investigate the selected three parameters. Thus, the shear capacity, deformation capacity, ductility and energy dissipation capacity of SCSW were determined. The research results show that: compared with studs, using stiffened ribs as shear connectors can significantly enhance the mechanical properties of SCSW; When the axial compression ratio is 0.3-0.4, the seismic performance of SCSW can be maximized; with the lowering of stiffener gap, the shear bearing capacity is greatly enhanced, and when the gap is lowered to a specific distance, the shear bearing capacity has no major affect; in addition, increasing the thickness of stiffeners can significantly increase the shear capacity, ductility and energy dissipation capacity of SCSW. With the rise in the thickness of angle stiffening ribs, the improvement rate of each mechanical property index slows down. Finally, the shear bearing capacity calculation formula of SCSW with angle stiffening ribs as shear connectors is derived. The average error between the theoretical calculation formula and the finite element calculation results is 8% demonstrating that the theoretical formula is reliable. This study can provide reference for the design of SCSW.

• Journal of Microbiology and Biotechnology
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• v.33 no.12
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• pp.1657-1670
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• 2023

This study aimed to evaluate the effects of Limosilactobacillus fermentum and Lactiplantibacillus plantarum isolated from human feces coordinating with inulin on the composition of gut microbiota and metabolic profiles in db/db mice. These supplements were administered to db/db mice for 12 weeks. The results showed that the Lactobacillaceae coordinating with inulin group (LI) exhibited lower fasting blood glucose levels than the model control group (MC). Additionally, LI was found to enhance colon tissue and increase the levels of short-chain fatty acids. 16S rRNA sequencing revealed that the abundance of Corynebacterium and Proteus, which were significantly increased in the MC group compared with NC group, were significantly decreased by the treatment of LI that also restored the key genera of the Lachnospiraceae_NK4A136_group, Lachnoclostridium, Ruminococcus_gnavus_group, Desulfovibrio, and Lachnospiraceae_UCG-006. Untargeted metabolomics analysis showed that lotaustralin, 5-hydroxyindoleacetic acid, and 13(S)-HpODE were increased while L-phenylalanine and L-tryptophan were decreased in the MC group compared with the NC group. However, the intervention of LI reversed the levels of these metabolites in the intestine. Correlation analysis revealed that Lachnoclostridium and Ruminococcus_gnavus_group were negatively correlated with 5-hydroxyindoleacetic acid and 13(S)-HpODE, but positively correlated with L-tryptophan. 13(S)-HpODE was involved in the "linoleic acid metabolism". L-tryptophan and 5-hydroxyindoleacetic acid were involved in "tryptophan metabolism" and "serotonergic synapse". These findings suggest that LI may alleviate type 2 diabetes symptoms by modulating the abundance of Ruminococcus_gnavus_group and Lachnoclostridium to regulate the pathways of "linoleic acid metabolism", "serotonergic synapse", and" tryptophan metabolism". Our results provide new insights into prevention and treatment of type 2 diabetes.

• Journal of Information Processing Systems
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• v.20 no.3
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• pp.337-344
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• 2024

It is a complex project to construct the standard system of sports events. Sports events standard system covers from the implementation plan to the evaluation work after the smooth implementation of sports events, involving many links. Large-scale sports events have extremely high media value. However, the successful organization and operation of large-scale sports events face many problems to be overcome, especially in terms of event safety. Although the organizers and organizers of large-scale events have invested many resources for the safe holding of sports events, violence similar to "football hooligans" in Europe is endless. At present, compared with Western countries, the standardization of sports events in China is low, and there is a problem of a late start and huge difference with Western developed countries. Knowing the construction of the standardization system's situation in China, we have summarized the data related to 15 sports events held in Chengdu is the last 5 years. By analyzing the problems in the process of holding these 15 events and the reflections of participants on the experience of sports events, the problems in the development of the standard system of sports events are discussed in depth. The final conclusion is that the system structure of China's sports events is not so good and athletes have a poor experience. China's sports event system still has many problems. Finally, we built a sports event standardization model using Internet of Things, and after a practical test we found that it has a good effect. Finally, we combined the current situation of sports event standardization system in China and put forward the following suggestions: laws and regulations related to the standard system of sports events must be formulated at the national level. The implementation level must strengthen the degree of integration of sports events and technology. To improve the quality of human resources in the management of sports events. The article puts forward targeted solutions, which play a great role in promoting the perfection and completeness of China's standard system for sports events. At the same time, it also promotes economic development and improves China's international status.

• Journal of Life Science
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• v.23 no.9
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• pp.1118-1125
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• 2013

Naringenin, a naturally occurring citrus flavonone, is a potentially valuable candidate for cancer chemotherapy. However, the cellular and molecular mechanisms responsible for its anticancer activity are largely unknown. In the present study, we attempted to elucidate the mechanisms responsible for naringenin-induced apoptosis in human leukemic U937 cells. We found that naringenin markedly inhibited the growth of U937 cells by decreasing cell proliferation and inducing apoptosis, which was associated with the activation of caspases. A pan-caspase inhibitor, z-VAD-fmk, significantly inhibited naringenin-induced U937 cell apoptosis, indicating that caspases are key regulators of apoptosis in response to naringenin in U937 cells. Although the levels of antiapoptotic Bcl-2 and proapoptotic Bax proteins remained unchanged in naringenin-treated U937 cells, Bcl-2 overexpression attenuated naringenin-induced apoptosis. Furthermore, combined treatment with naringenin and HA14-1, a small-molecule Bcl-2 inhibitor, effectively increased the apoptosis through enhancement of XIAP down-regulation, Bid cleavage, and caspase activation, suggesting that the synergistic effect was at least partially mediated through the death receptor-mediated apoptosis pathway.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.1
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• pp.247-250
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• 2012

Objective: To determine whether CDX2 and villin protein expression are associated with intestinal metaplasia (IM) in gastric cardiac mucosa and to explore the relationship with evolution of gastric cardiac adenocarcinoma (GCA). Methods: We studied 143 gastric cardiac biopsy or resection specimens from Henan province China, including 25 cardiac gastritis specimens with IM, 65 dysplasia specimens with IM and 35 gastric cardiac adenocarcinoma specimens and stained them for CDX2 and villin by the immunohistochemical SP method. 15 normal gastric cardiac biopsy specimens were also collected as control. Results: (1) Normal gastric mucosa presented no CDX2 and villin expression. The positive rates of CDX2 protein in cardiac gastritis with IM, dysplasia with IM, and carcinoma tissues were 84.0% (21/25), 66.7% (32/48) and 36.4% (20/55), respectively. While the positive rates of villin protein in cardiac gastritis with IM, dysplasia with IM, and carcinoma tissues were 76.0% (19/25), 70.8% (34/48) and 45.5% (25/55), respectively. There were significant differences among the three groups for both CDX2 and villin (P<0.01). Spearman's rank correlation coefficient(rho) showed a close correlation between the two proteins (r=0.843, P<0.01) and both were positively related with tumor differentiation (both P<0.05), but not associated with age, sex, invasion and metastasis of lymph node (P>0.05). Conclusion: Our results suggest that ectopic expression of CDX2 and villin may be involved in early-stage IM and tumorigenesis in gastric cardia and the expression of villin may be regulated by CDX2.