• Journal of the Korean Wood Science and Technology
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• v.26 no.1
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• pp.97-105
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• 1998

This study examined the combined using effects of urea-formaldehyde (UF) resin and emulsifiable methylene diphyenyl diisocyanate (EMDI) resin to overcome performance limit of three-layer particleboards commonly made by UF resin. Two adhesive adding methods were applied with three types of resin combination system to each layer of particleboards. The one was simultaneously spreading method with emulsified compound resin (UF and EMDI) while the other was separately spreading method with unemulsified EMDI resin after UF resin spreading. The performance of particleboards bonded with 2% EMDI resin to the inner layers(IL) were similar to that of controls bonded with 8% UF resin. In the case of the emulsified compound resin application to the all layers of particleboards, there were marked reinforcing effects of EMDI resin, although a small amount of EMDI resin was mixed with UF resin. Especially bending MOR after 24 hours cold water-immersion and thickness swelling after 2 hours hot water-immersion of compound resin-bonded particleboards were remarkably different from those of pure UF resin-bonded particleboards. It was found that separately spreading method with unemulsified EMDI resin was more effective than simultaneously spreading method with emulsified compound resin to sustain the internal bond strength of particleboards after 24 hours cold water-immersion. In the resin combination systems to outer layers/inner layers of particleboards, water resistance and strength properties were superior in order of UF+EMDI/UF+EMDI > UF/UF+EMDI > UF/UF. And water resistance of particleboards was greatly dependent upon EMDI resin level in any adhesive adding method.

• Mass Spectrometry Letters
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• v.5 no.4
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• pp.95-103
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• 2014

Characterization and studies of proteome are challenging because biological samples are complex, with a wide dynamic range of abundance. At present the proteins are identified by digestion into peptides, with subsequent identification of the peptides by mass spectrometry (MS). MS is a powerful technique for the purpose, but it cannot identify every peptide in such complex mixtures simultaneously. For accurate analysis and quantification it is important to separate the peptides first by chromatography into fractions of a size that MS can handle. With these less complex fractions, the probability is increased of identifying peptides of low abundance that would otherwise experience ion suppression effects due to the presence of peptides of high abundance. Enrichment for peptides with certain post-translational modifications helps to increase their detection rates as well. Electrostatic repulsion-hydrophilic interaction chromatography (ERLIC) is a mixed-mode chromatographic technique which combines the use of electrostatic repulsion and hydrophilic interaction. This review provides an overview of ERLIC and its various proteomics applications. ERLIC has been demonstrated to have good orthogonality to reverse phase liquid chromatography (RPLC), making it useful as a first dimension in multidimensional liquid chromatography (MDLC) and fractionation of digests in general. Peptides elute in order of their isoelectric points and polarity. ERLIC has also been successfully utilized for the enrichment for phosphopeptides and glycopeptides, facilitating their identification. In addition, it is promising for the study of peptide deamidation. ERLIC performs comparably well or better than established methods for these various applications, and serves as a viable and efficient workflow alternative.

• Health Policy and Management
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• v.30 no.2
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• pp.253-262
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• 2020

Background: The public health care system of a country is shaped and driven by its historical background as well as social, economic, and cultural structures. This study sheds light on the unique features, strengths, and weaknesses of the health insurance systems of South Korea (Korea) and Peru. Methods: The capacity mapping tool was used to explore the Korean and Peruvian population and geographical structures; health insurance laws, regulations, and policies; payment systems; eligibility and contribution collection; and long-term care insurance. Results: The study found that the Korean government took the lead in integrating multiple insurers into a single-payer system in an effort to reinforce and stabilize its health insurance system in 2000. Peru has been developed mixed model such based on taxes and contributions, to address a gap between different social classes. Peruvian government developed a two-axis system, one for low-income earners, financed by taxes, and another financed by contributions paid by workers and government officials in the formal sector. Peru has introduced many variations to its fee payment and insurer systems, target population, and coverage scope, and maintains its health insurance system accordingly to this day. Conclusion: The current study provides observation of the Health Insurance System in two different countries and helps to understand possible ways to improve the health insurance system in both countries. Based on this study, Peru will be able to see how its system differs from Korea's and benefit from the related policy implications.

• The Journal of Korean Academy of Prosthodontics
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• v.44 no.4
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• pp.383-393
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• 2006

Statement of problem : Limited research on flowable resin has been undertaken on its application directly on dentin associated with the adhesive systems. Purpose : This study was to evaluate the shear bond strengh and fracture aspect of flowable resin on human dentin with various types of dentin bonding adhesives with thermo cycling effect. Materials and methods: Filtek-Flow(3M ESPE, USA) was used as flowable resin and Eighty human molars were randomly divided into 4 groups : three dentin bonding adhesives (Scotchbond-Multipurpose : 3-step contentional system, One-Step : One-bottle system. Prompt L-Pop : All-in-one, self-etching primer) and 32% etching treatment without bonding adhesive as a control group. For evaluating their durability of bonding, each group was subdivided : storaging in the water at 37$^{\circ}C$(24 hours) and thermocycling (0$^{\circ}C$-55$^{\circ}C$, 30 seconds intervals, 1000 cycle). Shear bond strength tests were performed and resin-dentin interface and fracture mode were observed. Results were analysed by one-way ANOVA and Scheffe's multiple range test. Results and Conclusion : 1. At 0 cycle, the mean shear bond strength of One-Step exhibited the highest value of all groups(p<0.05), and there were no significant differences between Prompt L-Pop and Scotchbond-Multipurpose, Scotchbond-Multipurpose and control(p>0.05). After 1000 thermocycling, One-Step exhibited higher value than other groups(p<0.05), and there were no significant differences among other groups (p>0.05). 2. The shear bond strength of each group was significantly decreased after thermocycling except Scotchbond-Multipurpose (p>0.05). 3. The most common failure mode was adhesive type and mixed type, next in order.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.7
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• pp.1029-1036
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• 2017

Objective: In the livestock industry, the regulatory mechanisms of muscle proliferation and differentiation can be applied to improve traits such as growth and meat production. We investigated the regulatory pathway of MyoD and its role in muscle differentiation in quail myoblast cells. Methods: The MyoD gene was mutated by the clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 technology and single cell-derived MyoD mutant sublines were identified to investigate the global regulatory mechanism responsible for muscle differentiation. Results: The mutation efficiency was 73.3% in the mixed population, and from this population we were able to establish two QM7 MyoD knockout subline (MyoD KO QM7#4) through single cell pick-up and expansion. In the undifferentiated condition, paired box 7 expression in MyoD KO QM7#4 cells was not significantly different from regular QM7 (rQM7) cells. During differentiation, however, myotube formation was dramatically repressed in MyoD KO QM7#4 cells. Moreover, myogenic differentiation-specific transcripts and proteins were not expressed in MyoD KO QM7#4 cells even after an extended differentiation period. These results indicate that MyoD is critical for muscle differentiation. Furthermore, we analyzed the global regulatory interactions by RNA sequencing during muscle differentiation. Conclusion: With CRISPR/Cas9-mediated genomic editing, single cell-derived sublines with a specific knockout gene can be adapted to various aspects of basic research as well as in functional genomics studies.

• Physical Therapy Korea
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• v.25 no.3
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• pp.51-59
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• 2018

Background: Despite muscle latency times and patterns were used as broad examination tools to diagnose disease and recovery, previous studies have not compared the dominant arm to the non-dominant arm in muscle latency time and muscle recruitment patterns during reaching and reach-to-grasp movements. Objects: The present study aimed to investigate dominant and non-dominant hand differences in muscle latency time and recruitment pattern during reaching and reach-to-grasp movements. In addition, by manipulating the speed of movement, we examined the effect of movement speed on neuromuscular control of both right and left hands. Methods: A total of 28 right-handed (measured by Edinburgh Handedness Inventory) healthy subjects were recruited. We recorded surface electromyography muscle latency time and muscle recruitment patterns of four upper extremity muscles (i.e., anterior deltoid, triceps brachii, flexor digitorum superficialis, and extensor digitorum) from each left and right arm. Mixed-effect linear regression was used to detect differences between hands, reaching and reach-to-grasp, and the fast and preferred speed conditions. Results: There were no significant differences in muscle latency time between dominant and non-dominant hands or reaching and reach-to-grasp tasks (p>.05). However, there was a significantly longer muscle latency time in the preferred speed condition than the fast speed condition on both reaching and reach-to-grasp tasks (p<.05). Conclusion: These findings showed similar muscle latency time and muscle activation patterns with respect to movement speeds and tasks. Our findings hope to provide normative muscle physiology data for both right and left hands, thus aiding the understanding of the abnormal movements from patients and to develop appropriate rehabilitation strategies specific to dominant and non-dominant hands.

• Child Health Nursing Research
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• v.2 no.2
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• pp.35-44
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• 1996

The purpose of this study was to examine the knowledge and attitude of breast feeding and to explore the predictive variables for the intention of breast feeding of mothers. One hundred and thirty-five mothers who delivered at the D University hospital during the period of May to June in 1996 comprised the sample. Data were collected by questionnaire methods before discharge at the hospital. Data were analyzed using percent, 1-test, and logistic regression. The results were as follows : 1. During their pregnancy, majority of mothers (74.8%) got the breast feeding information. Information sources were book (34.5%), family and relatives(32.4%), mass media(24.3%), and professionals such as nurses and doctors (8.8% ). The frequently reported sources of most encouragement for breast feeding were mother in law(20.7%) and baby's father (11.1% ). 2. The mean score of the items of Knowledge and Attitude toward Breast Feeding Scale were 42.56 (SD=5.47) and 39.07(SD=5.15) , representing positive attitude toward breast feeding. The correlation between knowledge and attitude score was significant(r 〓.54, p<.001). Knowledge of breast feeding were significantly different between breast feeding intention group (including partial breast feeding) and artificial feeding intention group(t=2.79, p<.01) 3. Logistic regression analysis revealed that feeding method in the hospital, delivery type, knowledge toward breast feeding, disease related to pregnancy, complication related to delivery, and educational level of mother were predictives of the intention of breast feeding. 4. The most frequently rated reasons for the plan for mixed feeding were concern about insufficient milk (37.9%) and work(27.6%), The major reasons for plan for artificial milk feeding were having premature baby(25.9%) and maternal health problems including infection(14.8% ) and drug use due to chronic illness (14.8%). From the result of the study, it is recommended to develop supportive nursing intervention strategy to promote breast-feeding intention and practice. The intervention could be more effective to begin early in pregnancy and include teaching for breast feeding skills as well as information provision for positive attitude formation.

• Nuclear Engineering and Technology
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• v.49 no.1
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• pp.148-164
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• 2017

The focus on the issues surrounding spent nuclear fuel and lifetime extension of old nuclear power plants continues to grow nowadays. A transparent decision-making process to identify the best suitable nuclear fuel cycle (NFC) is considered to be the key task in the current situation. Through this study, an attempt is made to develop an equilibrium model for the NFC to calculate the material flows based on 1 TWh of electricity production, and to perform integrated multicriteria decision-making method analyses via the analytic hierarchy process technique for order of preference by similarity to ideal solution, preference ranking organization method for enrichment evaluation, and multiattribute utility theory methods. This comparative study is aimed at screening and ranking the three selected NFC options against five aspects: sustainability, environmental friendliness, economics, proliferation resistance, and technical feasibility. The selected fuel cycle options include pressurized water reactor (PWR) once-through cycle, PWR mixed oxide cycle, or pyroprocessing sodium-cooled fast reactor cycle. A sensitivity analysis was performed to prove the robustness of the results and explore the influence of criteria on the obtained ranking. As a result of the comparative analysis, the pyroprocessing sodium-cooled fast reactor cycle is determined to be the most competitive option among the NFC scenarios.

• Safety and Health at Work
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• v.9 no.3
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• pp.308-313
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• 2018

Background: A behavior-based safety initiative card-issuing system was introduced at a cement-manufacturing company in Zimbabwe in 2008 to try and curb accident occurrence. The purpose of this study was to evaluate the effectiveness of the Behaviour Based Safety Initiative card system as a tool used for reducing accident frequencies. Methods: A mixed-method approach that involving administering piloted questionnaires to 40 out of 244 randomly selected employees, making observations, and reviewing secondary data were done to collect data from different sources in the organization in 2013. A paired t-test was conducted to test whether there was significant difference in accident occurrence before and after the implementation of the BBSI. Scatterplots were also used to establish the correlation between the issuance of cards and the accident and injury occurrence. Results: The findings suggest that the introduction of the card system brought a significant decrease in accident and injury occurrence. A negative correlation between card issuance and accident occurrence was observed, i.e., the greater the number of cards issued, the fewer the number of accidents. It was also noted that the card system positively influenced the mindset of workers towards safe work practices. Conclusion: The card system had an influence on the reduction of accidents and injuries. The organization should leverage on issuing more cards to further reduce the number of accidents and injuries to zero.

• Journal of Korean Medical Science
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• v.33 no.53
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• pp.322.1-322.14
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• 2018

Background: Osteoprotegerin (OPG) plays protective roles against the development of vascular calcification (VC) which greatly contributes to the increased cardiovascular events in patients with chronic kidney disease (CKD). The present study aimed to find the non-traditional, kidney-related cardiovascular risk factors correlated to serum OPG and the effect of serum OPG on the arterial stiffness measured by brachial ankle pulse wave velocity (baPWV) in patients with the pre-dialysis CKD. Methods: We cross-sectionally analyzed the data from the patients in whom baPWV and the serum OPG were measured at the time of enrollment in a prospective pre-dialysis CKD cohort study in Korea. Results: Along with traditional cardiovascular risk factors such as age, diabetes mellitus, pulse pressure, and baPWV, non-traditional, kidney-related factors such as albuminuria, plasma level of hemoglobin, total $CO_2$ content, alkaline phosphatase, and corrected calcium were independent variables for serum OPG in multivariate linear regression. Reciprocally, the serum OPG was positively associated with baPWV in multivariate linear regression. The baPWV in the 3rd and 4th quartile groups of serum OPG were higher than that in the 1st quartile group after adjustments by age, sex and other significant factors for baPWV in linear mixed model. Conclusion: Non-traditional, kidney-related cardiovascular risk factors in addition to traditional cardiovascular risk factors were related to serum level of OPG in CKD. Serum OPG level was significantly related to baPWV. Our study suggests that kidney-related factors involved in CKD-specific pathways for VC play a role in the increased secretion of OPG into circulation in patients with CKD.