• Journal of Soil and Groundwater Environment
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• v.19 no.2
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• pp.16-24
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• 2014

To test the potential effects of extracellular electron shuttles (EES) on the rate and extent of heavy metal release from contaminated soils during microbial iron reduction, we created anaerobic batch systems with anthraquinone-2,6-disulfonate (AQDS) as a surrogate of EES, and with contaminated soils as mixed iron (hydr)oxides and microbial sources. Two types of soils were tested: Zn-contaminated soil A and As/Pb-contaminated soil B. In soil A, the rate of iron reduction was fastest in the presence of AQDS and > 3500 mg/L of total Fe(II) was produced within 2 d. This suggests that indigenous microorganisms can utilize AQDS as EES to stimulate iron reduction. In the incubations with soil B, the rate and extent of iron reduction did not increase in the presence of AQDS likely because of the low pH (< 5.5). In addition, less than 2000 mg/L of total Fe(II) was produced in soil B within 52 d suggesting that iron reduction by subsurface microorganisms in soil B was not as effective as that in soil A. Relatively high amount of As (~500 mg/L) was released to the aqueous phase during microbial iron reduction in soil B. The release of As might be due to the reduction of As-associated iron (hydr)oxides and/or direct enzymatic reduction of As(V) to As(III) by As-reducing microorganisms. However, given that Pb in liquid phase was < 0.3 mg/L for the entire experiment, the microbial reduction As(V) to As(III) by As-reducing microorganisms has most likely occurred in this system. This study suggests that heavy metal release from contaminated soils can be strongly controlled by subsurface microorganisms, soil pH, presence of EES, and/or nature of heavy metals.

• Toxicological Research
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• v.28 no.4
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• pp.209-216
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• 2012

The biological activity of particles is largely dependent on their size in biological systems. Dispersion in the aqueous phase has been both a critical impediment to and a prerequisite for particle studies. Carbon black has been used as a surrogate to investigate the biological effects of carbonaceous particles. Here, biocompatible methods were established to disperse carbon black into ultrafine and fine particles which are generally distinguished by the small size of 100 nm. Carbon black with a distinct particle size, N330 and N990 were suspended in blood plasma, cell culture media, Krebs-Ringer's solution (KR), or physiological salt solution (PSS). Large clumps were observed in all dispersion preparations; however, sonication improved dispersion - averaged particle sizes for N330 and N990 were $85.0{\pm}42.9$ and $112.4{\pm}67.9$ nm, respectively, in plasma; the corresponding sizes in culture media were $84.8{\pm}38.4$ and $164.1{\pm}77.8$ nm. However, sonication was not enough to disperse N330 less than 100 nm in either KR or PSS. Application of Tween 80 along with sonication reduced the size of N330 to less than 100 nm, and dispersed N990 larger than 100 nm ($73.6{\pm}28.8$ and $80.1{\pm}30.0$ nm for N330 and $349.5{\pm}161.8$ and $399.8{\pm}181.1$ nm for N990 in KR and PSS, respectively). In contrast, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) exhibited little effect. Electron microscopy confirmed the typical aciniform structure of the carbon arrays; however, zeta potential measurement failed to explain the dispersibility of carbon black. The methods established in this study could disperse carbon black into ultrafine and fine particles, and may serve as a useful model for the study of particle toxicity, particularly size-related effects.

• Toxicological Research
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• v.33 no.4
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• pp.283-290
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• 2017

The host immune system is the first line of host defense, consisting mainly of innate and adaptive immunity. Immunity must be maintained, orchestrated, and harmonized, since overactivation of immune responses can lead to inflammation and autoimmune diseases, while immune deficiency can lead to infectious diseases. We investigated the regulation of innate and adaptive immune cell activation by Artemisia capillaris and its components (ursolic acid, hyperoside, scopoletin, and scopolin). Macrophage phagocytic activity was determined using fluorescently labeled Escherichia coli, as an indicator of innate immune activation. Concanavalin A (ConA)- and lipopolysaccharide (LPS)-induced splenocyte proliferation was analyzed as surrogate markers for cellular and humoral adaptive immunity, respectively. Neither A. capillaris water extract (WAC) nor ethanol extract (EAC) greatly inhibited macrophage phagocytic activity. In contrast, WAC suppressed ConA- and LPS-induced proliferation of primary mouse splenocytes in a dose-dependent manner. Similarly, EAC inhibited ConA- and LPS-induced splenocyte proliferation. Oral administration of WAC in mice decreased ConA- and LPS-induced splenocyte proliferation, while that of EAC suppressed LPS-induced splenocyte proliferation. Repeated administration of WAC in mice inhibited ConA- and LPS-induced splenocyte proliferation. Ursolic acid, scopoletin, and scopolin reduced ConA- and LPS-induced primary mouse splenocyte proliferation, while hyperoside did not show such activity. These results indicate that A. capillaris and its components, ursolic acid, scopoletin, and scopolin, suppress ConA- and LPS-induced adaptive immune cell activation. The results suggest that A. capillaris is useful as a regulator of adaptive immunity for diseases involving excessive immune response activation.

• Asia pacific journal of information systems
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• v.16 no.3
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• pp.67-93
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• 2006

Some consumers prefer online and others prefer offline. What makes them prefer online or offline? There has been a lack of theoretical development to adequately explain consumers' channel switching behavior between traditional physical stores and new virtual stores. Through consumers' purchase decision processes, this study examined the reasons why consumers changed channels depending on purchase process stages. Consumer's purchase decision process could be divided into three stages: pre-purchase stage, purchase stage, and post-purchase stage. We used the intention of channel selection as a surrogate dependent variable of channel selection. And some constructs, that is, channel function, channel benefits, customer relationship benefits, and perceived behavioral control, were selected as independent variables. In buying look-and-feel products, it was identified that consumers preferred virtual stores to physical stores at pre-purchase stage. To put it concretely, all constructs except channel benefits were more influenced to consumers at virtual stores. This result implied that information searching function, which is a main function at pre-purchase stage, was better supported by virtual stores than physical stores. In purchase stage, consumers preferred physical stores to virtual stores. Specially, all constructs influenced much more to consumers at physical stores. This result implied that although escrow service and trusted third parties were introduced, consumers felt that financial risk, performance risk, social risk, etc. still remained highly online. Finally, consumers did not prefer any channel at post-purchase stage. But three independent variables, i.e. channel function, channel benefits, and customer relationship benefits, were significantly preferred at physical stores rather than virtual stores at post-purchase stage. So we concluded that physical stores were a little more preferred to virtual stores at post-purchase stage. Through this study, it was identified that most consumers might switch channels according to purchase process stages. So, first of all, sales representatives should decide that what benefits should be given them through virtual stores at the pre-purchase stage and through physical stores at the purchase and post-purchase stages, and then devise collaborative channel strategies.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.917-920
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• 2004

The migration potential of volatile organic solvents widely employed in the printing process of food packaging was investigated by using a closed experimental system, which contained a food sample and a paper sheet spiked with the contaminant solvents. The studied organic compounds included toluene and p,m,o-xylene which are relatively highly volatile. Typical food samples of caramel, beef jerky and butter were selected based on their chemical composition and were assigned to the migration system at 10, 25 and 4$0^{\circ}C$. The equilibrated migration level was very high with almost complete transfer in the butter with high fat, while caramel of high carbohydrate content and beef jerky of high protein showed migration degree of 37∼56% and 37∼77%, respectively. Temperature did significantly influence the migration on beef jerky with higher level at higher temperature. There was no difference in the migration level among the solvents.

• Journal of Aerospace System Engineering
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• v.13 no.5
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• pp.72-78
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• 2019

Inlet hammershock is the critical loads condition for designing the inlet duct structure of a fighter. The sudden flow reduction in engine compressor causes inlet hammershock with high pressure. The traditional method was used to combine extreme conditions (maximum speed, sea level altitude, and cold day) to analyze this compression wave inlet hammershock pressure. However, after the 90s there have been papers that presented the probabilistic approach for the inlet hammershock to achieve the appropriate design pressure. This study shows how to analyze the inlet hammershock pressure by making practical use of the Republic of Korea Air Force real flight usage data under probabilistic approach and then analyze approximately 30% decreased inlet hammershock pressure compared with the traditional valve.

• The Journal of the Korea Contents Association
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• v.19 no.2
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• pp.591-604
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• 2019

This study examines the process of internalization and elaboration of the logic of competition in the post-IMF era through the genealogy of the survival program. Post-IMF is based on disaster reality, which reveals a specific emotional structure related to the competition, if the narrative of overcoming the IMF event finds narrative models that can be sufficiently reconciled between communityism and individual success. This study also examines the process of disaster preparedness through survival form and narrative structure embedded in such form. Thus, this study reconstructed the diachronic change to track the change of the survival program and the subsequent narrative change. Relative to the time of the healing-mentor, the survival program seems to be declining, but rather seems to have created a new transition through the logic of self-development contained in the healing-mentoring discourse. this logic leads to be ghettoized hierarchy of preferences. Now, the survival program is to perform fantastic surrogate satisfaction by delegating competition to a narrow self-directed area rather than to a big empathy within the community.

• BMB Reports
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• v.52 no.2
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• pp.133-138
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• 2019

Upon viral infection, the 2', 5'-oligoadenylate synthetase (OAS)-ribonuclease L (RNaseL) system works to cleave viral RNA, thereby blocking viral replication. However, it is unclear whether OAS proteins have a role in regulating gene expression. Here, we show that OAS1 and OAS3 act as negative regulators of the expression of chemokines and interferon-responsive genes in human macrophages. Clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein-9 nuclease (Cas9) technology was used to engineer human myeloid cell lines in which the OAS1 or OAS3 gene was deleted. Neither OAS1 nor OAS3 was exclusively responsible for the degradation of rRNA in macrophages stimulated with poly(I:C), a synthetic surrogate for viral double-stranded (ds)RNA. An mRNA sequencing analysis revealed that genes related to type I interferon signaling and chemokine activity were increased in $OAS1^{-/-}$ and $OAS3^{-/-}$ macrophages treated with intracellular poly(I:C). Indeed, retinoic-acid-inducible gene (RIG)-I- and interferon-induced helicase C domain-containing protein (IFIH1 or MDA5)-mediated induction of chemokines and interferon-stimulated genes was regulated by OAS3, but Toll-like receptor 3 (TLR3)- and TLR4-mediated induction of those genes was modulated by OAS1 in macrophages. However, stimulation of these cells with type I interferons had no effect on OAS1- or OAS3-mediated chemokine secretion. These data suggest that OAS1 and OAS3 negatively regulate the expression of chemokines and interferon-responsive genes in human macrophages.

• The Journal of Society for e-Business Studies
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• v.23 no.4
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• pp.127-136
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• 2018

With the increased value in digital contents, the influence of social media has increased exponentially over the past years. Focused around those in their teens and twenties, social media has spread its influence to people regardless of one's age or gender. This increased attention is reflected by the public's interest in pets, especially those dealt with in the personal media sector. This paper will focus on the two most popular Korean cat youtube channels called "CreamHeroes" and "SuriNoel." By analyzing the top thirty most viewed videos on each channel, real time streaming, goods based on the cats starring on the channel, and comments left by the channels' subscribers, it can be concluded that people watching videos categorized as "Viewnimal" derive surrogate pleasure from their viewings. The following creates the potential for increased conversation regarding the subject of shelter animals and animal abuse.

• Journal of Breast Cancer
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• v.21 no.4
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• pp.399-405
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• 2018

Purpose: Vesicle-associated membrane protein 8 (VAMP8) is a soluble N-ethylmaleimide-sensitive factor receptor protein that participates in autophagy by directly regulating autophagosome membrane fusion and has been reported to be involved in tumor progression. Nevertheless, the expression and prognostic value of VAMP8 in breast cancer (BC) remain unknown. This study aimed to evaluate the clinical significance and biological function of VAMP8 in BC. Methods: A total of 112 BC samples and 30 normal mammary gland samples were collected. The expression of VAMP8 was assessed in both BC tissues and normal mammary gland tissues via a two-step immunohistochemical detection method. Results: The expression of VAMP8 in BC tissues was significantly higher than that in normal breast tissues. Furthermore, increased VAMP8 expression was significantly correlated with tumor size (p=0.007), lymph node metastasis (p=0.024) and recurrence (p=0.001). Patients with high VAMP8 expression had significantly lower cumulative recurrence-free survival and overall survival (p<0.001 for both) than patients with low VAMP8 expression. In multivariate logistic regression and Cox regression analyses, lymph node metastasis and VAMP8 expression were independent prognostic factors for BC. Conclusion: VAMP8 is significantly upregulated in human BC tissues and can thus be a practical and potentially effective surrogate marker for survival in BC patients.