• Journal of Life Science
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• v.28 no.8
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• pp.992-998
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• 2018

Cancer cells grow in an environment composed of various components that supports tumor growth. Major cell types in the tumor microenvironment are fibroblast, endothelial cells and immune cells. All of these cells communicate with cancer cells. Among infiltrating immune cells as an abundant component of solid tumors, macrophages are a major component of the tumor microenvironment and orchestrates various aspects of immunity. The complex balance between pro-tumoral and anti-tumoral effects of immune cell infiltration can create a chronic inflammatory microenvironment essential for tumor growth and progression. Macrophages express different functional programs in response to microenvironmental signals, defined as M1 and M2 polarization. Tumor-associated macrophages (TAM) secret many cytokines, chemokines and proteases, which also promote tumor angiogenesis, growth, metastasis and immunosuppression. TAM have multifaceted roles in the development of many tumor types. TAM also interact with cancer stem cells. This interaction leads to tumorigenesis, metastasis, and drug resistance. TAM obtain various immunosuppressive functions to maintain the tumor microenvironment. TAM are characterized by their heterogeneity and plasticity, as they can be functionally reprogrammed to polarized phenotypes by exposure to cancer-related factors, stromal factors, infections, or even drug interventions. Because TAMs produce tumor-specific chemokines by the stimulation of stromal factors, chemokines might serve as biomarkers that reflect disease activity. The evidence has shown that cancer tissues with high infiltration of TAM are associated with poor patient prognosis and resistance to therapies. Targeting of TAM in tumors is considered a promising therapeutic strategy for anti-cancer treatment.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.191-197
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• 2015

We investigated the physicochemical properties and volatile flavor compounds in Taiwan Apple Mango (TAM) and Philippines Carabao Mango (PCM). The volatile flavor compounds were extracted using solid-phase microextraction (SPME) and analyzed by GC/MS. TAM and PCM have significantly different chemical composition, except for their crude ash. The moisture and crude fat contents were higher in TAM, whereas the crude protein and carbohydrate contents were higher in PCM. The major free sugars in order of concentration were sucrose, fructose, and glucose. We identified 56 and 59 volatile flavor compounds in TAM and PCM, respectively. Terpenes and their derivatives comprised 94.42% of the volatile flavor compounds in TAM, but only 63.79% of those in PCM. The acidic compound contents were higher in PCM than in TAM. ${\delta}$-3-Carene was the dominant flavor compound in these two mango cultivars. ${\alpha}$-Copaene, ${\alpha}$-guaiene, germacrene D, ${\alpha}$-bulnesene, and ${\gamma}$-gurjunene were found only in TAM, whereas ${\beta}$-myrcene, ${\alpha}$-phellandrene, ${\beta}$-phellandrene, ${\alpha}$-terpinolene, and cis-3-hexenyl butyrate were identified in PCM. Based on the results, we suggest that these compounds might contribute to the distinguishing flavor properties in different varieties of mango.

• East Asian Journal of Business Economics (EAJBE)
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• v.8 no.3
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• pp.15-24
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• 2020

Purpose - New technologies allow service providers to integrate all the customer information within and between contact channels so that they can offer individualized services. The availability of new mobile devices enables retailers to interact with customers through countless channels (Rigby, 2011). The objective of this research is to examine customers' attitudes toward O2O (on-line to off-line) services and their intention to use based on the Technology Acceptance Model (TAM). Research design, data, and methodology - Utilizing the TAM model, the mediating effect of the users' attitudes toward O2O services on the relationship among perceived ease of use, perceived usefulness, perceived risks and intention to use are to be investigated. Results - The result shows that the perceived ease of use, perceived usefulness, perceived risks have a significant effect on customers' attitudes toward O2O services. It is also revealed that the attitude toward O2O services has a mediating effect among perceived ease of use, perceived usefulness, perceived risks and intention to use. Conclusions - The boundary between on-line and off-line is eroding and various services based on the O2O platform are growing. The results of this study and managerial implications can be applied to O2O platform operators or enterprises planning to sharp on their competitiveness edge through offering variations of service channels.

• Korean Management Science Review
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• v.21 no.1
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• pp.1-17
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• 2004

A separate and distinct interaction with both the actual e-vendor and with its IT web site interface is at the heart of online shopping. Previous research has established, accordingly, that online purchase intention is the product of customer assessments of IT itself, specifically its perceived usefulness and ease-of-use(TAM). Since perceived usefulness and perceived ease of use are such a fundamental driver of usage intentions, it is important to understand the determinants of this construct and how their influence changes over the voluntariness towards the usage intention. The reason for voluntariness as a moderating variable is that it had the serious effect to the motivating in the making willingness of the internet shopping-mall usage. A better understanding of the determinants of perceived usefulness and perceived ease of use to the usage intention would enable us to design web site interventions that would increase user acceptance and usage of internet shopping-mall. Therefore, the goal of the present research is to extend TAM to include additional key determinants of TAM and to understand how the effects of these determinants change with the voluntariness of the usage intention of the internet shopping-mall.

• Korean Management Science Review
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• v.19 no.2
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• pp.25-39
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• 2002

This study suggests a revised TAM (Technology Acceptance Model)-based performance evaluation model in MS (management science) education. Recently, many MS education programs are developed on the basis of computer and Internet communication technology. Previous researchers used TAM as an individual performance evaluation model, and proved that perceived usefulness and perceived ease of use are the substantive successful factors. This study provides a revised TAM-based conceptual framework for understanding what is involved in improving university MS education and what might be implied by conducting research on its improvement. It is argued in this research that three sets of forces and conditions have a direct and indirect impact on MS education ; first, each student has self efficacy and it is a critical determinant of behavior next, the use of Internet-based information system at MS education affects on the renewal of MS education : and finally, perceived usefulness and perceived ease of use have impacts on behavioral intention and actual system usage. This research concludes with suggestions for which direction this framework provides for future research on the premise and limits of efforts to renew MS education in university.

• Journal of Korean Society on Water Environment
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• v.21 no.6
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• pp.651-658
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• 2005

The Non-parametric Analysis is powerful in data test especially for the non- normality water quality data. The data at three monitoring stations of the Tam-Jin River were evaluated for their normality using Skewness, Q-Q plot and Shapiro-Willks tests. Various constituent of water quality data including temperature, pH, DO, SS, BOD, COD, TN and TP in the period of January 1994 to December 2004 were used as dataset. Shapiro-Willks normality test was carried out for a test 5% significance level. Most water quality data except DO at monitoring stations 1 and 2 showed that data does not normally distributed. It is indicating that non-parametric method must be used for a water quality data. Therefore, a homogeneity was conducted by Mann-Whitney U test (p<0.05). Two stations were paired in three pairs of such stations. Differences between stations 1, 2 and stations 1, 3 for pH, BOD, COD, TN and TP were meaningful, but Tam-Jin 2 and 3 stations did not meaningful. In addition, a narrow gap of the water quality ranges is not a difference. Categories in which all three pairs of stations (1 and 2, 2 and 3, 1 and 3) in the Tam-Jin River showed difference in water quality were analyzed on TN and TP. The results of in this research suggest a right analysis in the homogeneity test of water quality data and a reasonable management of pollutant sources.

• BMB Reports
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• v.55 no.2
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• pp.81-86
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• 2022

Macrophages are a major cellular component of innate immunity and are mainly known to have phagocytic activity. In the tumor microenvironment (TME), they can be differentiated into tumor-associated macrophages (TAMs). As the most abundant immune cells in the TME, TAMs promote tumor progression by enhancing angiogenesis, suppressing T cells and increasing immunosuppressive cytokine production. N-myc downstream-regulated gene 2 (NDRG2) is a tumor suppressor gene, whose expression is down-regulated in various cancers. However, the effect of NDRG2 on the differentiation of macrophages into TAMs in breast cancer remains elusive. In this study, we investigated the effect of NDRG2 expression in breast cancer cells on the differentiation of macrophages into TAMs. Compared to tumor cell-conditioned medium (TCCM) from 4T1-mock cells, TCCM from NDRG2-over-expressing 4T1 mouse breast cancer cells did not significantly change the morphology of RAW 264.7 cells. However, TCCM from 4T1-NDRG2 cells reduced the mRNA levels of TAM-related genes, including MR1, IL-10, ARG1 and iNOS, in RAW 264.7 cells. In addition, TCCM from 4T1-NDRG2 cells reduced the expression of TAM-related surface markers, such as CD206, in peritoneal macrophages (PEM). The mRNA expression of TAM-related genes, including IL-10, YM1, FIZZ1, MR1, ARG1 and iNOS, was also downregulated by TCCM from 4T1-NDRG2 cells. Remarkably, TCCM from 4T1-NDRG2 cells reduced the expression of PD-L1 and Fra-1 as well as the production of GM-CSF, IL-10 and ROS, leading to the attenuation of T cell-inhibitory activity of PEM. These data showed that compared with TCCM from 4T1-mock cells, TCCM from 4T1-NDRG2 cells suppressed the TAM differentiation and activation. Collectively, these results suggest that NDRG2 expression in breast cancer may reduce the differentiation of macrophages into TAMs in the TME.

• The Journal of Information Systems
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• v.14 no.2
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• pp.133-154
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• 2005

The objective of this study is to find the factors influencing the use of mobile service. We extracted critical study variables according to literature reviews about adoption of information systems, those under the internet environment and mobile internet adoption for theoretical foundation. TAM suggested by Davis(1985) has explained the acceptance mechanism with the following constructs: perceived usefulness, perceived ease of use, attitude toward use, behavioral intention and actual usage. After studying prior literature reviews, this study investigated the group of people using mobile services. The result of study claims that it has same results with previous TAM, especially between personal innovativeness and attitude toward use have strong statistical relations. On the other hand, there haven't been any statistical relations between perceived ease of use and perceived usefulness and between perceived usefulness and behavioral intention, either. In conclusion, use of mobile service can be promoted by developing various kinds of mobile service, designing device and interface to use mobile service more convenience and familiar, stimulating user's innovative characters and recognizing mobile service more useful in real life.

• Asia pacific journal of information systems
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• v.16 no.2
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• pp.159-181
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• 2006

The purpose of this research is to identify the factors affecting user acceptance of mobile banking. To test the hypotheses, this research incorporates trust to extend the model. This study investigates the causal relationship among four factors; perceived ease of use, perceived usefulness, trust, and intention to use in mobile banking. This study also identifies the elements by which these factors are influenced. The result finds that facilitation condition and self-efficacy are significant elements affecting perceived ease of use. System quality, perceived ease of use and trust are significant elements affecting perceived usefulness, However, social influence is found to be not significant. System quality and perceived ease of use are significant elements affecting trust. Conclusively, perceived ease of use, perceived usefulness and trust are significant factors affecting the user acceptance in Mobile banking.

• Journal of the Korean Wood Science and Technology
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• v.26 no.2
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• pp.38-44
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• 1998

A new device that uses turbulent air for mixing wood fibers with thermoplastic fibers was designed and its mixing effectiveness was evaluated in wood fiber and polypropylene fiber composites. Composites made by the turbulent air mixing (TAM) process performed better than composites made by the conventional Rando-Webber forming or nonwoven web process with an additional needling step. Thus, the TAM process proved to be a simple and efficient method in mixing wood fibers with short thermoplastic fibers for the production of wood fiber and thermoplastic fiber composites.