• Korean Journal of Materials Research
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• v.4 no.3
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• pp.329-333
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• 1994

A large number of grain boundaries were seen to crack in near-eutectic solder joints of leadless ceramic chip carriers (LLCC's) during thermal cycling at temperature ranges from -$35^{\circ}C$ to +$125^{\circ}C$ with lhr time period. One potential explanation for this type of cracking might be the presence of embrittling species on the boundary. Although there do not appear to be any instances reported in the literature of solders being embrittled by small amounts of contaminating species, the possibility of such an occurrence exists. The potential presence of impurities located at crack surfaces was inspected using Scanning Auger Microprobe(SAM) and it was found that intergranular cracking could be accomplished by the oxidation of the grain boundary. A physical model for fatigue crack growth was introduced, in which grain boundary separation took place under oxidation facilitated by sliding.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.1 no.1
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• pp.74-82
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• 2020

Predictions of suitable habitat areas can provide important information pertaining to the risk assessment and management of alien plants at early stage of their establishment. Here, we predict the invasion potential of Muhlenbergia capillaris (pink muhly) in South Korea using five bioclimatic variables. We adopt four models (generalized linear model, generalized additive model, random forest (RF), and artificial neural network) for projection based on 630 presence and 600 pseudo-absence data points. The RF model yielded the highest performance. The presence probability of M. capillaris was highest within an annual temperature range of 12 to 24℃ and with precipitation from 800 to 1,300 mm. The occurrence of M. capillaris was positively associated with the precipitation of the driest quarter. The projection map showed that suitable areas for M. capillaris are mainly concentrated in the southern coastal regions of South Korea, where temperatures and precipitation are higher than in other regions, especially in the winter season. We can conclude that M. capillaris is not considered to be invasive based on a habitat suitability map. However, there is a possibility that rising temperatures and increasing precipitation levels in winter can accelerate the expansion of this plant on the Korean Peninsula.

• Molecules and Cells
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• v.20 no.3
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• pp.446-451
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• 2005

Diap1 is an essential Drosophila cell death regulator that binds to caspases and inhibits their activity. Reaper, Grim and Hid each antagonize Diap1 by binding to its BIR domain, activating the caspases and eventually causing cell death. Reaper and Hid induce cell death in a Ring-dependent manner by stimulating Diap1 auto-ubiquitination and degradation. It was not clear that how Grim causes the ubiquitination and degradation of Diap1 in Grim-dependent cell death. We found that Grim stimulates poly-ubiquitination of Diap1 in the presence of UbcD1 and that it binds to UbcD1 in a GST pull-down assay, so presumably promoting Diap1 degradation. The possibility that dBruce is another E2 interacting with Diap1 was examined. The UBC domain of dBruce slightly stimulated poly-ubiquitination of Diap1 in Drosophila extracts but not in the reconstitution assay. However Grim did not stimulate Diap1 poly-ubiquitination in the presence of the UBC domain of dBruce. Taken together, these results suggest that Grim stimulates the poly-ubiquitination and presumably degradation of Diap1 in a novel way by binding to UbcD1 but not to the UBC domain of dBruce as an E2.

• Macromolecular Research
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• v.15 no.3
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• pp.205-210
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• 2007

Collagen is the major structural protein of connective tissues. It can be used as a prosthetic biomaterial applicable to artificial skin, tendon, ligaments, and collagen implants. The objective of this study is to investigate the possibility of realizing wound dressing medical products by the synthesis of composite materials with collagen and a biodegradable polymer, PLLA, via a surface modification process. Type I collagen was obtained from pig skin by a separation process. The structural characteristics of the extracted collagen were confirmed by SDS-polyacrylamide (PAcr) gel electrophoresis (PAGE) and FTIR. Also, PLLA-g-PAcr was synthesized by the radical polymerization of acrylamide initiated by AIBN in the presence of PLLA. The surface of PLLA was modified by the presence of the acrylamide residues. The structural characteristics of the copolymer were analyzed by FTIR, $^1H-NMR$ and contact angle measurements. The water uptake and WVTR of the collagen/PLLA-g-PAcr composite tended to increase with increasing collagen concentration and with decreasing EDC concentration.

• Journal of Korean society of Dental Hygiene
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• v.19 no.3
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• pp.409-419
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• 2019

Objectives: The purpose of this study was to analyze the factors affecting antibiotic prescription in dental outpatients. Methods: The present study was conducted using data from the National Health Insurance Service - National Sample Cohort. We analyzed prescriptions issued in the dental outpatient department in 2015, for adults over 19 years of age. Antibiotic prescription rates and mean prescription days were analyzed by sex, age, insurance type, presence of diabetes mellitus and hypertension, season in treatment, type of dental institution, and location of dental institution. Multivariate logistic regression was also performed to analyze the factors affecting antibiotic prescription in dental outpatients. Results: A total of 257,038 prescriptions were analyzed. The mean prescription days of antibiotics in dental outpatients were $3.04{\pm}1.08days$, and the prescription rate was 93.0%. Two variables (presence of diabetes mellitus and insurance type) were excluded from the multivariate logistic regression analysis model because they did not significantly affect antibiotic prescription. The possibility of antibiotic prescription was higher in men ${\geq}61years$ of age and those with hypertension. Furthermore, antibiotics were most frequently prescribed in dental clinics rather than dental hospitals, and more frequently in Busan compared to other areas (p<0.001). Conclusions: Several factors were determined to affect antibiotic prescription, and detailed guidelines for consistent antibiotic prescription are needed.

• Journal of Distribution Science
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• v.20 no.1
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• pp.87-98
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• 2022

Purpose: This research investigates whether the existence of preannouncing price discount before purchase has an effect on after regret about purchasing and price fairness perception. Moreover, this paper examines whether the preannouncing effects on regret (or price fairness perception) are moderated by motive inference type (or brand trust). Research design, data and methodology: This experimental design consisted of total 8 between-subjects full factorial, which is completed by 2 (preannouncing price discount before purchase) × 2 (motive inference type) × 2 (consumer's brand trust level). Results: First, regret (or price fairness) differs depending on the presence/absence of preannouncing price discount before purchase and price discount motive inference type. Second, interaction effect of preannouncing price discount presence/absence before purchase and price discount motive inference type on regret (or price fairness) after purchase differs depending on motive inference type (or brand trust). Conclusions: Preannouncing external cue could decrease the possibility of consumers to regret and prevent consumers perceiving price change as unfair. Thus, corporations should sufficiently explain to consumers about preannouncing and specific reason of price fall in order to decrease regret caused by price fall and to increase price fairness perception from preannouncing effect.

• The Plant Pathology Journal
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• v.40 no.4
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• pp.377-389
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• 2024

The possibility of new viruses emerging in various regions worldwide has increased due to a combination of factors, including climate change and the expansion of international trading. Plant viruses spread through various transmission routes, encompassing well-known avenues such as pollen, seeds, and insects. However, research on potential transmission routes beyond these known mechanisms has remained limited. To address this gap, this study employed metatranscriptomic analysis to ascertain the presence of plant viruses in imported frozen fruits, specifically cherries and blueberries. This analysis aimed to identify pathways through which plant viruses may be introduced into countries. Virome analysis revealed the presence of six species of plant viruses in frozen cherries and blueberries: cherry virus A (CVA), prunus necrotic ringspot virus (PNRSV), prune dwarf virus (PDV), prunus virus F (PrVF), blueberry shock virus (BlShV), and blueberry latent virus (BlLV). Identifying these potential transmission routes is crucial for effectively managing and preventing the spread of plant viruses and crop protection. This study highlights the importance of robust quality control measures and monitoring systems for frozen fruits, emphasizing the need for proactive measures to mitigate the risk associated with the potential spread of plant viruses.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.6
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• pp.125-138
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• 2019

This study aims to highlight the possibility in identifying species composition of fish communities using the environmental DNA (eDNA) metabarcoding technique, from both of the technical introduction and the pilot test at urban ecological streams. This new emerging survey technique using eDNA is getting popular in the world as a compensating way for the conventional field survey. However, the application to the domestic cases has yet to be studied. We attempted to use this technique for identifying fish species observed at four survey points in Hwangguji-chon, Suwon City. As a result, the detected number of species by eDNA sampled once in May was significantly matched with the total number of observed species in annual field surveys. Additionally eDNA results indicated the presence possibility of the unobserved species in field last year, even though the validation may be required. This survey technique seems to be more efficient and applicable to diverse situations of the fields and species, thereby needs to be studied further. We discussed the pros and cons of the application and summarized the research directions in future.

• Journal of Korean Philosophical Society
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• v.146
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• pp.163-192
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• 2018

In the philosophy of Louis Labelle, the subject of "good and evil", which is rarely discussed in modern philosophy, emerges as a very important concept. In his reasoning, the notion of evil starts from a passive stipulation of the Scholastic philosophy of "the lack of being", but he defined the evil, which actually exists in the world with more positive sense as a willing force destroying "life and values". In his reasoning that defines "the presence of evil" as "le scandale du monde", all humans have the possibility of evil as an attitude of will, and the presence of evil in the world and in human society is inevitable. On the other hand, because the outcome of evil appears as physical and mental "pain", the human's attitude toward pain, which attempts to deny suffering, induces a moral will to overcome this evil. The moral anguish, which is the "internal suffering" that we have in front of the presence of evil, makes us conscious of becoming a "moral being", and people become self-satisfied here. Although painful, self-satisfaction and happiness about becoming a moral being is the only occasion and motive for man to overcome this by opposing the presence of evil. In other words, Lavelle's thoughts for good and evil are based on "moral psychologism", and the "coherence of psychological horizons and ethical horizons" between rejection of suffering and moral agony enables "ethical optimism" that man constantly overcomes evil and produces good. This is clearly an advanced modern application of scholasticism on the concept of evil.

• Journal of Plant Biotechnology
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• v.5 no.3
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• pp.149-155
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• 2003

Metabolic engineering for production of isoflavones in nonlegume plants could distribute the health benefits of these phytoestrogens in more widely-consumed grains. Series of investigation to check the ability of the heterologous isoflavone synthase enzyme to interact with the endogenous phenylpropanoid pathway have been conducted. Overall, results provide possibility of production of isoflavonoids in several plant tissue systems including soybean and nonlegumes. In tissue that undergoes naturally enhanced synthesis of anthocyanins, genistein production was enhanced. In a monocot cell system, introduced expression of a transcription factor regulating genes of the anthocyanin pathway was effective in conferring the ability to produce genistein in the presence of the isoflavone synthase gene. However, in this case the intermediate accumulated to high levels indicating an inefficiency in its conversion. Introduction of a third gene, chalcone reductase, provided the ability to synthesize an additional substrate of isoflavone synthase resulting in production of the isoflavone daidzein. These research efforts provide insight into requirements for metabolic engineering for isoflavone production in nonlegume dicot and monocot tissues.