• Biomolecules & Therapeutics
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• v.27 no.2
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• pp.216-221
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• 2019

The c-Met protein is a receptor tyrosine kinase involved in cell growth, proliferation, survival, and angiogenesis of several human tumors. Overexpression of c-Met has been found in gastric cancers and correlated with a poor prognosis. Indirubin is the active component of Danggui Longhui Wan, which is a traditional Chinese antileukemic recipe. In the present study, we tested the anti-cancer effects of an indirubin derivative, LDD-1937, on human gastric cancer cells SNU-638. When we performed the in vitro kinase assay against the c-Met activity, LDD-1937 inhibited the activity of c-Met. This result was confirmed by immunoblot and immunofluorescence of phosphorylated c-Met. Immunoblot analysis showed that LDD-1937 decreased the expression of the Erk1/2, STAT3, STAT5, and Akt, downstream proteins of c-Met. In addition, LDD-1937 reduced the cell viability and suppressed colony formation and migration of SNU-638 cells. Furthermore, LDD-1937 induced $G_2/M$ phase arrest in the SNU-638 cells by decreasing the expression levels of cyclin B1 and CDC2. Cleaved-PARP, an apoptosis-related protein, was up-regulated in cells treated with LDD-1937. Overall, this study suggests that LDD-1937 may be a novel small-molecule with therapeutic potential for selectively inhibiting c-Met and c-Met downstream pathways in human gastric cancers overexpressing c-Met.

• Korean Chemical Engineering Research
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• v.59 no.2
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• pp.174-179
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• 2021

Recently, hybrid coal research is underway to upgrade low-grade coal. The hybrid coal is made by mixing low-grade coal with bioliquids such as molasses, sugar cane, and lignin. In the case of lignin used here, a large amount of lignin is included in the wastewater of the papermaking process, and thus, research on hybrid coal production using the same is attracting attention. However, since a large amount of metal ions are contained in the lignin wastewater from the papermaking process, substances that corrode the generator are generated during combustion, and the amount of fly ash is increased. To solve this problem, it is essential to remove metal ions in the lignin wastewater. In this study, metal ions were removed by ion exchange with a alumina hollow fiber membrane coated with K-Phillipsite (K-PHI) zeolite. The alumina hollow fiber membrane used as the support was prepared by the nonsolvent induced phase separation (NIPS) method, and K-PHI seeds were prepared by hydrothermal synthesis. The prepared K-PHI seed was seeded on the surface of the support and coated by secondary growth hydrothermal synthesis. The characteristic of prepared coating membrane was analyzed by Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), Energy Dispersive Spectroscopy (EDX), and the concentration of metal ions before and after ion exchange was measured by Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES). The extraction amount of K+ is 86 mg/kg, and the extraction amount of Na+ is 54.9 mg/kg. Therefore, K-PHI zeolite membrane has the potential to remove potassium and sodium ions from the solution and can be used in acidic lignin wastewater.

• The Journal of the Acoustical Society of Korea
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• v.40 no.2
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• pp.169-175
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• 2021

Recently, an ultrasound hologram and its applications have gained attention in the ultrasound research field. However, the determination technique of transmit signal phases, which generate a hologram, has not been significantly advanced from the previous algorithms which are time-consuming iterative methods. Thus, we applied the deep learning technique, which has been previously adopted to generate an optical hologram, to generate an ultrasound hologram. We further examined the Deep learning-based Holographic Ultrasound Generation algorithm (Deep-HUG). We implement the U-Net-based algorithm and examine its generalizability by training on a dataset, which consists of randomly distributed disks, and testing on the alphabets (A-Z). Furthermore, we compare the Deep-HUG with the previous algorithm in terms of computation time, accuracy, and uniformity. It was found that the accuracy and uniformity of the Deep-HUG are somewhat lower than those of the previous algorithm whereas the computation time is 190 times faster than that of the previous algorithm, demonstrating that Deep-HUG has potential as a useful technique to rapidly generate an ultrasound hologram for various applications.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.12
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• pp.85-94
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• 2018

The purpose of this paper was to propose a model that recognizes potential users' emotional response toward design by classifying Electroencephalography(EEG). Studies in neuroscience and psychology have made an effort to recognize subjects' emotional response by analyzing EEG data. And this approach has been adopted in design since it is critical to monitor users' subjective response in the preface of design. Moreover, the building design process cannot be reversed after construction, recognizing clients' affection toward design alternatives plays important role. An experiment was conducted to record subjects' EEG data while they view their most/least liked images of small-house designs selected by them among the eight given images. After the recording, a subjective questionnaire, PANAS, was distributed to the subjects in order to describe their own affection score in quantitative way. Google TensorFlow was used to build and train the model. Dataset for model training and testing consist of feature columns for recorded EEG data and labels for the questionnaire results. After training and testing, the measured accuracy of the model was 0.975 which was higher than the other machine learning based classification methods. The proposed model may suggest one quantitative way of evaluating design alternatives. In addition, this method may support designer while designing the facilities for people like disabled or children who are not able to express their own feelings toward alternatives.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.30 no.4
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• pp.405-411
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• 2020

Objectives: The objectives of this study were to investigate whether airborne fibers were released to the outside air from the asbestos removal area in buildings, and to confirm the existence of asbestos fibers in samples using transmission electron microscopy(TEM). Methods: A total of 1,295 samples was collected from inside and outside 155 asbestos removal areas. To investigate the release of asbestos fibers from the removal area, samples were collected at three locations, such as an entrance to change room, an exit of negative pressure unit(NPU) and perimeter areas. Samples were also collected in the removal area prior to and after removal activity. All samples were analyzed by phase contrast microscopy(PCM) and one-tenth of the samples was analyzed using TEM to discriminate asbestos fibers. Results: During the asbestos removal activity, 27(4.1%) of 662 samples collected outside the removal area showed airborne fiber concentrations equal to or in excess of 0.01 f/cc, the permissible emission standard of the Korean Ministry of Environment. Further, 111 samples were analyzed using TEM. The distribution of asbestos fiber concentrations was log-normal. It was found that 51 of 111 samples(46%) contained asbestos fibers. Conclusions: There is a potential risk of asbestos exposure among neighbors and the public outside the asbestos removal areas. It is recommended that the asbestos removal work be conducted strictly following the specifications required by government and/or professional organizations.

• Journal of Microbiology and Biotechnology
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• v.30 no.12
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• pp.1885-1895
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• 2020

Rumex japonicus Houtt (RJH) is a valuable plant used in traditional medicine to treat several diseases, such as scabies and jaundice. In this study, Jurkat cell growth inhibitory extracts of R. japonicus roots were subjected to bioassay-guided fractionation, resulting in the isolation of three naphthalene derivatives (3-5) along with one anthraquinone (6) and two phenolic compounds (1 and 2). Among these compounds, 2-methoxystypandrone (5) exhibited potent anti-proliferative effects on Jurkat cells. Analysis by flow cytometry confirmed that 2-methoxystypandrone (5) could significantly reduce mitochondrial membrane potential and promote increased levels of mitochondrial reactive oxygen species (ROS), suggesting a strong mitochondrial depolarization effect. Real-time quantitative polymerase chain reaction (qPCR) analysis was also performed, and the results revealed that the accumulation of ROS was caused by reduced mRNA expression levels of heme oxygenase (HO-1), catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD). In addition, 2-methoxystypandrone (5) triggered strong apoptosis that was mediated by the arrest of the G0/G1 phase of the cell cycle. Furthermore, 2-methoxystypandrone (5) downregulated p-IκB-α, p-NF-κB p65, Bcl2, and Bcl-xl and upregulated BAX proteins. Taken together, these findings revealed that 2-methoxystypandrone (5) isolated from RJH could potentially serve as an early lead compound for leukemia treatment involving intracellular signaling by increasing mitochondrial ROS and exerting anti-proliferative effects.

• Journal of Environmental Science International
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• v.30 no.1
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• pp.97-108
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• 2021

In the current study, MIL-101(Cr)-SO3H[HCl] as metal-organic frameworks (MOFs) was fabricated via a hydrothermal method. The physicochemical properties of the synthesized material were characterized using XRD, FT-IR, FE-SEM, TEM, and BET surface area analysis. The XRD diffraction pattern of the prepared MIL-101(Cr)-SO3H[HCl] was similar to previously reported patterns of MIL-101(Cr) type materials, indicating successful synthesis of MIL-101(Cr)-SO3H[HCl]. The FT-IR spectrum revealed the molecular structure and functional groups of the synthesized MIL-101(Cr)-SO3H[HCl]. FE-SEM and TEM images indicated the formation of rectangular parallelopiped structures in the prepared MIL-101(Cr)-SO3H[HCl]. Furthermore, the EDS spectrum showed that the synthesized material consisted of the elements of Cr, O, S, and C. The fabricated MIL-101(Cr)-SO3H[HCl] was then employed as an adsorbent for the removal of Sr2+ and Cs+ from aqueous solutions. The adsorption kinetics and adsorption isotherm models were studied in detail. The maximum adsorption capacities of MIL-101(Cr)-SO3H[HCl] for Sr2+ and Cs+ according to pH (3, 5.3~5.8, 10) were 35.05, 43.35, and 79.72 mg/g and 78.58, 74.58, and 169.74 mg/g, respectively. These results demonstrate the potential of the synthesized MOFs, which can be effectively applied as an adsorbent for the removal of Sr2+ and Cs+ ions from aqueous solutions and other diverse applications.

• Current Applied Physics
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• v.18 no.11
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• pp.1403-1409
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• 2018

In the present study, the $SrMoO_4:Eu^{3+}$ phosphors has been synthesized through hydro-thermal co-precipitation method, and single factor and orthogonal experiment method was adopted to find optimal synthesis condition. It is interesting to note that hydro-thermal temperature is a prominent effect on the luminescent intensity of $SrMoO_4:Eu^{3+}$ red phosphor, followed by co-precipitation temperature, calcining time, and the doping amount of $Eu^{3+}$. The optimal synthesis conditions were obtained: hydro-thermal temperature is $145^{\circ}C$, co-precipitation temperature is $35^{\circ}C$, the calcining time is 2.5 h, and the doping amount of activator $Eu^{3+}$ is 25%. Subsequently, the crystalline particle size, phase composition and morphology of the synthesized phosphors were evaluated by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The results show that these phosphors possess a scheelite-type tetragonal structure, and the particle size is about $0.2{\mu}m$. Spectroscopic investigations of the synthesized phosphors are carried out with the help of photo-luminescence excitation and emission analysis. The studies reveal that $SrMoO_4:Eu^{3+}$ phosphor efficiently convert radiation of 394 nm-592 and 616 nm for red light, and the luminescence intensity of $SrMoO_4:Eu^{3+}$ phosphors is improved. $SrMoO_4:Eu^{3+}$ phosphors may be a potential application for enhancing the efficiency of white LEDs.

• International Journal of Advanced Culture Technology
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• v.9 no.1
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• pp.70-78
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• 2021

It is true that the police have been faithful to the role of the regime's sewer and committed many disruptions and errors, and have been criticized and criticized by the public. It should now be the foundation of the democratic police and an organization supported by the people. The problem is that the quality, personality, and values of 130,000 police officers should be changed and should be in line with the spirit of the times. One of the theories of police corruption is the "rotten apple hypothesis." The theory is that there is a high possibility that the entire police force will be corrupted, as if the defective apple in the apple box is rotten and the whole apple is rotten, without filtering out potential corrupt police officers during the recruitment phase. In other words, the cause of corruption is based on personal flaws. This study intends to analyze the causes of police corruption and improvement measures. The purpose of this study is to ensure that police officers in charge of national security are usually armed with ethics and good conduct. The police should be trusted by the people and need a stronger prescription for police corruption. In this respect, this study aims to solve the corruption problem of police officials, analyze anti-corruption, and find out what are the desirable countermeasures. The main study methods of this study are as follows; First, we first tried to collect data through research on corruption-related literature. The analysis was focused on the related papers of police corruption and government reports. Second, police corruption theory and anti-corruption alternatives were analyzed. It was reviewed focusing on the theory of corruption or translated data. Third, a literature survey was analyzed to examine the National Police Agency's perception of police corruption. Based on these research methods, we tried to derive the desirable control measures for the hypothesis of police corruption. This study is believed to have contributed to supporting the organizational corruption and culture of the apple box, including the personality of the individual's values, which is a rotten apple theory of police corruption.

• Journal of Microbiology and Biotechnology
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• v.31 no.12
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• pp.1615-1623
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• 2021

Picropodophyllotoxin (PPT), an epimer of podophyllotoxin, is derived from the roots of Podophyllum hexandrum and exerts various biological effects, including anti-proliferation activity. However, the effect of PPT on colorectal cancer cells and the associated cellular mechanisms have not been studied. In the present study, we explored the anticancer activity of PPT and its underlying mechanisms in HCT116 cells. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to monitor cell viability. Flow cytometry was used to evaluate cell cycle distribution, the induction of apoptosis, the level of reactive oxygen species (ROS), assess the mitochondrial membrane potential (Δψm), and multi-caspase activity. Western blot assays were performed to detect the expression of cell cycle regulatory proteins, apoptosis-related proteins, and p38 MAPK (mitogen-activated protein kinase). We found that PPT induced apoptosis, cell cycle arrest at the G1 phase, and ROS in the HCT116 cell line. In addition, PPT enhanced the phosphorylation of p38 MAPK, which regulates apoptosis and PPT-induced apoptosis. The phosphorylation of p38 MAPK was inhibited by an antioxidant agent (N-acetyl-L-cysteine, NAC) and a p38 inhibitor (SB203580). PPT induced depolarization of the mitochondrial inner membrane and caspase-dependent apoptosis, which was attenuated by exposure to Z-VAD-FMK. Overall, these data indicate that PPT induced G1 arrest and apoptosis via ROS generation and activation of the p38 MAPK signaling pathway.