• Journal of Korea Water Resources Association
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• v.57 no.3
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• pp.209-223
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• 2024

In the context of the fourth industrial revolution, data-driven decision-making has increasingly become pivotal. However, the integrity of data analysis is compromised if data quality is not adequately ensured, potentially leading to biased interpretations. This is particularly critical for water level data, essential for water resource management, which often encounters quality issues such as missing values, spikes, and noise. This study addresses the challenge of noise-induced data quality deterioration, which complicates trend analysis and may produce anomalous outliers. To mitigate this issue, we propose a noise removal strategy employing Wavelet Transform, a technique renowned for its efficacy in signal processing and noise elimination. The advantage of Wavelet Transform lies in its operational efficiency - it reduces both time and costs as it obviates the need for acquiring the true values of collected data. This study conducted a comparative performance evaluation between our Wavelet Transform-based approach and the Denoising Autoencoder, a prominent machine learning method for noise reduction.. The findings demonstrate that the Coiflets wavelet function outperforms the Denoising Autoencoder across various metrics, including Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), and Mean Squared Error (MSE). The superiority of the Coiflets function suggests that selecting an appropriate wavelet function tailored to the specific application environment can effectively address data quality issues caused by noise. This study underscores the potential of Wavelet Transform as a robust tool for enhancing the quality of water level data, thereby contributing to the reliability of water resource management decisions.

• Korean Journal of Radiology
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• v.22 no.9
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• pp.1451-1461
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• 2021

Objective: Adequate methods of combining T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) to assess complete response (CR) to chemoradiotherapy (CRT) for rectal cancer are obscure. We aimed to determine an algorithm for combining T2WI and DWI to optimally suggest CR on MRI using visual assessment. Materials and Methods: We included 376 patients (male:female, 256:120; mean age ± standard deviation, 59.7 ± 11.1 years) who had undergone long-course CRT for rectal cancer and both pre- and post-CRT high-resolution rectal MRI during 2017-2018. Two experienced radiologists independently evaluated whether a tumor signal was absent, representing CR, on both post-CRT T2WI and DWI, and whether the pre-treatment DWI showed homogeneous hyperintensity throughout the lesion. Algorithms for combining T2WI and DWI were as follows: 'AND,' if both showed CR; 'OR,' if any one showed CR; and 'conditional OR,' if T2WI showed CR or DWI showed CR after the pre-treatment DWI showed homogeneous hyperintensity. Their efficacies for diagnosing pathologic CR (pCR) were determined in comparison with T2WI alone. Results: Sixty-nine patients (18.4%) had pCR. AND had a lower sensitivity without statistical significance (vs. 62.3% [43/69]; 59.4% [41/69], p = 0.500) and a significantly higher specificity (vs. 87.0% [267/307]; 90.2% [277/307], p = 0.002) than those of T2WI. Both OR and conditional OR combinations resulted in a large increase in sensitivity (vs. 62.3% [43/69]; 81.2% [56/69], p < 0.001; and 73.9% [51/69], p = 0.008, respectively) and a large decrease in specificity (vs. 87.0% [267/307]; 57.0% [175/307], p < 0.001; and 69.1% [212/307], p < 0.001, respectively) as compared with T2WI, ultimately creating additional false interpretations of CR more frequently than additional identification of patients with pCR. Conclusion: AND combination of T2WI and DWI is an appropriate strategy for suggesting CR using visual assessment of MRI after CRT for rectal cancer.

• Korean Journal of Clinical Pharmacy
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• v.13 no.1
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• pp.29-39
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• 2003

Neurodegenerative disorders are associated with apoptosis as a causing factor or an inducer. On the other hand, it has been reported that epigallocatechin gallate (EUG), one of antioxidants and flavonoids, and z-VAD-fmk, a nonselective caspase inhibitor, suppress oxidative-radical-stress-induced apoptosis. However, it is not yet known what is the effects of EGCG and z-VAD-fmk on the apoptotic pathway is through phosphoinositide 3-kinase (PI3K), Akt and glycogen synthase kinase-3 (GSK-3) as well as mitochondria, caspase-3 and poly (ADP-ribose) polymerase (PARP). We investigated the effects of EGCG by using $H_2O_2$ treated N18D3 cells, mouse DRG hybrid neurons. Methods: Following 30 min $100\;{\mu}m\;H_2O_2$ exposure, the viability of N18D3 cells (not pretreated vs. EGCG or z-VAD-fmk pretreated) was evaluated by using MTT assay. The effect of EGCG on immunoreactivity (IR) of cytochrome c, caspase-3, PARP, PI3K/Akt and GSK-3 was examined by using Western blot, and was compared with that of z-Y4D-fmk. Results: EGCG or z-VAD-fmk pretreated N18D3 cells showed increased viability. Dose-dependent inhibition of caspase-3 activation accompanied by PARP cleavage were demonstrated by pretreatment of both agents. However, inhibition of cytochrome c release was only detected in EGCG pretreated N18D3 cells. On the pathway through PI3K/Akt and GSK-3, however, the result of Western blot in EGCG pretreated N18D3 cells showed decreased IR of Akt and GSK-3 and increased IR of p85a PI3K, phosphorylated Akt and GSK-3, and contrasted with that in z-VAD-fmk pretreated N18D3 cells showing no changes on each molecule. Conclusion: These data show that EGCG affects apoptotic pathway through upstream signal including PI3K/Akt and GSK-3 pathway as well as downstream signal including cytochrome c and caspase-3 pathway. Therefore, these results suggest that EGCG mediated activation of PI3K/Akt and inhibition GSK-B could be new potential therapeutic strategy for neurodegenerative diseases associated with oxidative injury.

• Journal of Life Science
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• v.28 no.2
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• pp.240-246
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• 2018

Efferent and afferent sympathetic nerves are closely related to the development of hypertension and heart failure. Catheter-based renal sympathetic denervation (RDN) is implemented as a strategy to treat resistant hypertension. We investigated whether RDN procedure causes inflammatory damage on myocardium in the early phase of sympathetic denervation. Twenty-five female swine were divided into 3 groups: normal control (Normal, n=5), sham-operated control (Sham, n=5), and RDN groups (RDN, n=15). The RDN group was further subdivided into 3 subgroups according to the time of sacrifice: immediately (RDN-0, n=5), 1 week (RDN-1, n=5), and 2 weeks (RDN-2, n=5) after RDN. There were no significant changes in the clinical parameters between the normal control and sham-operated group using contrast-media. In the myocardium, inflammatory cytokines, $IL-1{\beta}$ and $TNF-{\alpha}$ increased at the first week, and then decreased at the second week after RDN. Anti-inflammatory cytokine, IL-10 increased immediately, and then decreased at the second week after RDN. Caspase-1 activity and apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) expression increased immediately after RDN until the second week. However, nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing protein 3 (NLRP3) expression did not show any significant differences among the groups. The RDN can cause acute myocardial inflammation through activation of caspase-1 and $IL-1{\beta}$. We should pay attention to protecting against early inflammatory myocardial damage after RDN.

• Journal of Plant Biotechnology
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• v.35 no.4
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• pp.307-316
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• 2008

Transposon-mediated insertional mutagenesis is one of powerful strategy for assessing functions of genes in higher plants. In this report, we have selected highly susceptible and tolerance plant by screening about high salt (3% NaCl) and cold stresses ($4^{\circ}C$) from F2 seeds of 30,000 Ac/Ds insertional mutagenesis lines in rice (Oryza sativa L. cv. Dongjin). In order to identify the gene tagging, insertion of Ds element was analyzed by Southern blot and these results revealed that 19 lines were matched genotype of selected lines with phenotype from the first selected 212 lines, and 13 lines have one copy of Ds elements. The Franking Sequence Tags (FSTs) of selected mutant lines showed high similarities with the following known function genes: signal transduction and regulation of gene expression (transpoter, protease family protein and apical meristem family protein), osmotic stress response (heat shock protein, O-methyltransferase, glyceraldehyde-3-phosphate dehydrogenase and drought stress induce protein), vesicle trafficking (SYP 5 family protein) and senescence associated protein. The expression pattern of 19 genes were analyzed using RT-PCR under the abiotic stresses of 9 class; 250mM NaCl, osmotic, drought, 3% $H_2O_2$, $100{\mu}M$ ABA, $100{\mu}M$ IAA, 0.1 ppm 2,4-D, $4^{\circ}C$ cold and $38^{\circ}C$ high temperature. Isolated knock-out genes showed the positive response about 250 mM NaCl, drought, $H_2O_2$, PEG, IAA, 2,4-D, ABA treatment and low ($4^{\circ}C$) and high temperature ($38^{\circ}C$). The results from this study indicate that function of selected knock-out genes could be useful in improving of tolerance to abiotic stresses as an important transcriptional activators in rice.

• Radiation Oncology Journal
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• v.22 no.2
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• pp.77-90
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• 2004

Purpose: The purpose of this review Is to provide an update on novel radiation treatments for head and neck cancer Recent Findings: Despite the remarkable advances In chemotherapy and radiotherapy techniques, the management of advanced head and neck cancer remains challenging. Epidermal growth factor receptor (EGFR) Is an appealing target for novel therapies In head and neck cancer because not only EGFR activation stimulates many important signaling pathways associated with cancer development and progression, and importantly, resistance to radiation. Furthermore, EGFR overexpression Is known to be portended for a worse outcome in patients with advanced head and neck cancer. Two categories of compounds designed to abrogate EGFR signaling, such as monoclonal antibodies (Cetuxlmab) and tyrosine kinase inhibitors (ZD1839 and 051-774) have been assessed and have been most extensively studied In preclinical models and clinical trials. Additional TKIs In clinical trials include a reversible agent, Cl-1033, which blocks activation of all erbB receptors. Encouraging preclinical data for head and neck cancers resulted In rapid translation Into the clinic. Results from Initial clinical trials show rather surprisingly that only minority of patients benefited from EGFR inhibition as monotherapy or In combination with chemotherapy. In this review, we begin with a brief summary of erbB- mediated signal transduction. Subsequently, we present data on prognostic-predictive value of erbB receptor expression in HNC followed by preclinlcal and clinical data on the role of EGFR antagonists alone or in combination with radiation In the treatment of HNC. Finally, we discuss the emerging thoughts on resistance to EGFR biockade and efforts In the development of multiple-targeted therapy for combination with chemotherapy or radiation. Current challenges for investigators are to determine (1 ) who will benefit from targeted agents and which agents are most appropriate to combine with radiation and/or chemotherapy, (2) how to sequence these agents with radiation and/or cytotoxlc compounds, (3) reliable markers for patient selection and verification of effective blockade of signaling in vivo, and (4) mechanisms behind intrinsic or acquired resistance to targeted agents to facilitate rational development of multi-targeted therapy, Other molecuiar-targeted approaches In head and neck cancer were briefly described, Including angloenesis Inhibitors, farnesyl transferase inhibitors, cell cycle regulators, and gene therapy Summary: Novel targeted theraples are highly appealing in advanced head and neck cancer, and the most premising strategy to use them Is a matter of intense Investigation.

• Journal of Gastric Cancer
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• v.5 no.3 s.19
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• pp.191-199
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• 2005

Background: Though infections of Helicobacter pylori (H. pylori) are closely associated with activation of host angiogenesis, the underlying mechanisms, as well as the strategy for its prevention, have not been identified. Here, we investigated a causal role of H. pylori infection in angiogenesis of gastric mucosa and a potent inhibitory effect of a gastric proton pump inhibitor (PPI) on the gastropathy. Materials and Methods: A comparative analysis of CD 34 expression in tissues obtained from 20 H. pylori-associated gastritis and 18 H. pylori-negative gastritis patients was performed. Expression of $HIF-1{\alpha}$ and VEGF were tested by using RT-PCR. To evaluate the direct effect of H. pylori infection on differentiation of endothelial HUVEC cells, we carried out an in vitro angiogenesis assay. Results: H. pyfori-associated gastritis tissues showed significantly higher density of $CD34^+$ blood vessels than did H. pylori-negative gastritis tissues, and the levels were well correlated with expressions of $HIF-1{\alpha}$. Conditioned media from H. pylori-infected gastric mucosal cells stimulated a tubular formation of HUVEC cells. We also found a significant inhibitory effect of PPI, an agent frequently used for H. pylori eradication, on H. pylori-induced angiogenesis. This drug effectively inhibited the phosphorylation of MAP kinase ERK1/2, which is a principal signal for H. pylori-induced angiogenesis. Conclusion: The fact that PPls can down-regulate H. pylori-induced angiogenesis suggest that anti-angiogenic treatment using PPI may be a preventive approach for H. pylori-associated carcinogenesis.

• Journal of The Korean Astronomical Society
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• v.52 no.1
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• pp.11-21
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• 2019

Intensive Monitoring Survey of Nearby Galaxies (IMSNG) is a high cadence observation program monitoring nearby galaxies with high probabilities of hosting supernovae (SNe). IMSNG aims to constrain the SN explosion mechanism by inferring sizes of SN progenitor systems through the detection of the shock-heated emission that lasts less than a few days after the SN explosion. To catch the signal, IMSNG utilizes a network of 0.5-m to 1-m class telescopes around the world and monitors the images of 60 nearby galaxies at distances D < 50 Mpc to a cadence as short as a few hours. The target galaxies are bright in near-ultraviolet (NUV) with $M_{NUV}$ < -18.4 AB mag and have high probabilities of hosting SNe ($0.06SN\;yr^{-1}$ per galaxy). With this strategy, we expect to detect the early light curves of 3.4 SNe per year to a depth of R ~ 19.5 mag, enabling us to detect the shock-heated emission from a progenitor star with a radius as small as $0.1R_{\odot}$. The accumulated data will be also useful for studying faint features around the target galaxies and other science projects. So far, 18 SNe have occurred in our target fields (16 in IMSNG galaxies) over 5 years, confirming our SN rate estimate of $0.06SN\;yr^{-1}$ per galaxy.

• Cross-Cultural Studies
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• v.52
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• pp.165-194
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• 2018

Employing Fairclough's critical discourse analysis (CDA), the purpose of this study was to analyze linguistically significant features, intertextuality, and sociocultural practice focusing on selected editorials of The Global Times, $Hu{\acute{a}}nqi{\acute{u}}$ Shíbào on the 2018 United States-China Trade War. The editorial titled "With the strong will of 'the War to Resist America and Aid Chosun,' let us go through the trade war against America" focused on the use of 'war' related vocabulary in the frame of 'war.' First, "Trade War" and "War to Resist America and Aid Chosun" are examples that reveal metaphors and a war frame. Second, "Strategy" is used positively for China but negatively towards America. Third, various war related words are used. Fourth, cases of allusion illustrate war. Intertextuality in terms of discourse practice pertains to two findings. First, The Global Times, $Hu{\acute{a}}nqi{\acute{u}}$ Shíbào repeatedly uses the phrase 'equivalent revenge.' That is because the expression enables China to justify their counterattack and such war that China may wage can be interpreted as just counterattack much like a self-defense mechanism. Second, the expression, 'the counterattack is not intended but it is not fearful' is repeated in several editorials of the newspaper. The reasons are the following: 1) it is used to appeal to the public, 2) by invoking the feeling of fear, the public should be understand why they should unite, and 3) the expression, "it is not fearful" is used to preserve China's global image and "the counterattack is not intended" is used to signal China's will to America. The whole expression is a good example of intertextuality that repetitively illustrates the intended meaning of China in nine editorials in the newspaper within three months, March 23-June 17, 2018. Finally, sociocultural practice is manipulated through the editorial for disseminating the Chinese government's hegemonic ideology. First, it is clear that the core national project, "China Manufacturing 2025" cannot be abandoned. Second, by calling for "War to Resist America and Aid Chosun" the editorial is manipulated to condemn and intimidate America, avoid dissent of the people, appeal to the people, and empower the government. Third, China somehow wants to open up the possibility of negotiation with the United Sates.

• Asia Marketing Journal
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• v.15 no.4
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• pp.131-159
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• 2014

Corporate rebranding has been evident in the qualitative corporate rebranding studies as an imposed organizational change that induces mixed reactions and ambivalent attitudes among consumers. Corporate rebranding for the established and familiar corporate brands leads to more ambivalent attitudes as these companies represent larger targets for disparaging information. Consumers are found to hold both positive and negative reactions toward companies and brands that they are familiar with. Nevertheless, the imposed change assumption and ambivalent attitude, in particular corporate rebranding, have never been widely explored in the quantitative corporate rebranding studies. This paper aims to provide a comprehensive empirical examination of the ambivalence towards rebrandingrebranded brand attitude-purchase intention relationships. The author proposes that corporate rebranding for familiar corporate brands is a double-edged sword that not only raises the expectation for better performance, but also induces conflicted and ambivalent attitudes among consumers. These consumers' ambivalent attitudes are influenced by both the parent brands-related and general attitude factors which further affect their rebranded brand attitude and purchase intention. A total of 156 useable questionnaires were collected from Malaysian working adults; and two established Malaysian airfreight operators were utilized as the focal parent brands. The study found a significant impact of prior parent brand attitudes on ambivalence towards rebranding (ATR). The parent brand attitudes served as anchors in influencing how new information was processed (Mazaheri et al., 2011; Sherif & Hovland, 1961) and closely related to behavioral intention (Prislin & Quellete, 1996). The ambivalent attitudes experienced were higher when individuals held both positive and negative reactions toward the parent brands. Consumers also held higher ambivalent attitudes when they preferred one of the parent brands; while disliked the other brand. The study also found significant relationships between the lead brand and the rebranded brand attitude; and between the partner brands and ATR. The familiar but controversial partner brand contributed significantly to the ambivalent attitudes experienced; while the more established lead brand had significant impact on the rebranded brand attitude. The lead and partner brands, though both familiar, represented different meanings to consumers. The author attributed these results to the prior parent brand attitudes, the skepticism and their general ambivalence toward the corporate rebranding. Both general attitude factors (i.e. skepticism and general ambivalence towards rebranding) were found to have significant positive impacts on ATR. Skeptical individuals questioned the possibility of a successful rebranding (Chang, 2011) and were more careful with their evaluations toward 'too god to be true' or 'made in heaven' pair of companies. The embedded general ambivalent attitudes that people held toward rebranding could be triggered from the associative network by the ambiguous situation (Prislin & Quellete, 1996). In addition, the ambivalent rebranded brand attitude was found to lower down purchase intention, supporting Hanze (2001), Lavine (2001) and van Harreveld et al. (2009)'s studies. Ambivalent individuals were found to prefer delay decision making by choosing around the mid-ranged points in 'willingness to buy' scale. The study provides several marketing implications. Ambivalence management is proven to be important to corporate rebranding to minimize the ambivalent attitudes experienced. This could be done by carefully controlling the parent brands-related and general attitude factors. The high ambivalent individuals are less confident with their own conflicted attitudes and are motivated to get rid of the psychological discomfort caused by these conflicted attitudes (Bell & Esses, 2002; Lau-Gesk, 2005; van Harreveld et al., 2009). They tend to process information more deeply (Jonas et al., 1997; Maio et al., 2000; Wood et al., 1985) and pay more attention to message that provides convincible arguments. Providing strong, favorable and convincible message is hence effective in alleviating consumers' ambivalent attitudes. In addition, brand name heuristic could be utilized because the rebranding strategy sends important signal to consumers about the changes that happen or going to happen. The ambivalent individuals will pay attention to both brand name heuristic and rebranding message in their effort to alleviate the psychological discomfort caused by ambivalent attitudes. The findings also provide insights to Malaysian and airline operators for a better planning and implementation of corporate rebranding exercise.