• Journal of Microbiology and Biotechnology
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• v.19 no.7
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• pp.727-733
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• 2009

Heat shock protein 70 kDa (hsp70), a molecular chaperone involved in folding of nascent proteins, has been studied for its ability to activate innate and specific immunity. High purity hsp70 preparation is generally required for immunization experiments, because endotoxins and other immunologically active contaminants may affect immune responses independently of hsp70. We have developed a novel modification of E. coli-expression medium that enabled a simple two-step production and purification method for endotoxin-free recombinant hsp70. During Ni-NTA-based affinity purification of hsp70, a contaminating protein from host E. coli cells, L-glutamine-n-fructose-6-phosphate aminotransferase (GFAT), was identified. By testing various compounds, supplementation of growth medium with a GFAT metabolite,N-acetylglucosamine, was found to reduce GFAT expression and increase the total hsp70 yield five times. The new protocol is based on column purification of His-tagged hsp70 protein produced by E. coli with the modified medium, followed by endotoxin removal by Triton X-114 extraction. This approach yielded hsp70 with high purity and minimal endotoxin contamination, making the final product acceptable for immunization experiments. In summary, a simple modification of growth medium allowed production of recombinant mouse hsp70 in high yield and purity, thus compatible with immunological studies. This protocol may be useful for production of other Histagged proteins expressed in E. coli.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.2
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• pp.136-142
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• 2012

Various factors affecting on the bioassay were investigated. Experiments with a low mixture ratio (cell to toxicant solution) of 0.5 : 9.5 (v/v) produced observable bioluminescence intensity for assay. Both sodium lactate and potassium nitrate stimulate bioluminescence activity; 2.6~4.0 times of control. Distilled water and MSM, which gave non significant effects on the bioluminescence activity, were determined as proper diluent or extract solutions. A wide range of toxic responses of metals and organics were observed. In general, organics were much less sensitive than metals. Samples collected from eleven sites showed the bioluminescence activity ranging from 29 to 111% of the control. Significant correlation between toxicity and total metal contents was not observed, but the toxicity of two groups, sorted based on the contaminated arsenic concentration in soils, was 44% and 20%, showing considerable differences.

• Journal of the Korean Society for information Management
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• v.37 no.1
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• pp.107-126
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• 2020

With the rapid increase in information and the development of information technologies, the importance of information management is increasing for individuals. The study aimed to examine how the motivations or disturbance factors of personal information management affect college students. First, the motivation and disturbance factors of personal information management were derived through the analysis of previous studies, and the effects of these factors on information organization and information management activities were analyzed. For this purpose, an online questionnaire was conducted for college students at a university in Seoul and a total of 593 valid responses were analyzed. The study found that the motivations or disturbance factors of personal information management influenced personal information management behavior. The study extends the literature of personal information management by analyzing the information management behavior of individuals and identifying the factors influencing such behavior. Furthermore, the finding of the study suggests the practical implications that it is essential to provide personal information management education so that college students can manage personal information efficiently.

• The Journal of the Korea Contents Association
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• v.18 no.10
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• pp.644-656
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• 2018

This study focused on relationships among leisure involvement, experience quality and behavioral intention in the urban parks. A total of 335 were collected, and during the data refinement process, 39 questionnaires were eliminated from the study due to partial and inconsistent responses. thus leading to 296 usable questionnaires out of 335. In the final result, 296 questionnaires were coded for the analysis purpose. The hypothesized conceptual model was used to analyze the Descriptive Analysis and Frequency Analysis, Exploratory Factor Analysis, and Multiple Regression Analysis using SPSS 24.0. The result indicated this: residents' experience quality in urban parks depends on more attraction and centrality of leisure involvement than on the self-experience quality of leisure involvement. The results of this study also indicate that not all experience dimensions are important for resulting in positive behavioral intentions to urban parks. The quality of education, esthetic, and escape experience showed a significant predictor of behavioral intentions, while the quality of entertainment experience did not show a significant positive relationship with behavioral intentions.

• Journal of Labour Economics
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• v.30 no.2
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• pp.119-148
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• 2007

Foreign outsourcing, otherwise known as off-shoring, has become a matter of intense public debate and great concern in both developed countries and developing countries. Yet, there is a lack of good data on foreign outsourcing since the early 1990's. This paper presents updated measures of foreign outsourcing for the recent period. Its main findings are that the share of foreign-sourced goods in total manufactured inputs almost doubled-from 12.4 percent to 22.7 percent between 1987 and 2003. I then look at the relationship between the measure of foreign outsourcing activity and wages in US manufacturing industries in recent years from 1998 to 2003. The results show that for all workers, the outsourcing level is statistically significantly and negatively associated with industry wage premiums. The estimate suggests that a magnitude of 0.9 - a 9% decrease in industry wage premiums tends to accompany a 10% increase in industry outsourcing level. Outsourcing has a bigger effect on the less-skilled workers-industry outsourcing level increases by 10% and industry wage premiums decrease by about 11% in the case of less-skilled workers.

• Journal of Convergence for Information Technology
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• v.10 no.10
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• pp.196-202
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• 2020

This study explores conceptions of learning management and examines the effects on study approach and critical thinking. Undergraduates majoring or minoring in management were gathered through convenient sampling and participated in the online survey. A total of 88 responses were analyzed. The results reveal that there is no significant gender or grade difference on conceptions of learning management. Conceptions of "test" and "seeing in a new way" are associated with deep study approach, whereas conceptions of 'test' is associated with surface study approach. Conceptions of "seeing in a new way" has a significant effect on critical thinking. The findings may inform redesign of instruction or curriculum especially focusing on improving high-quality thinking skills as the learning outcomes.

• International Journal of Naval Architecture and Ocean Engineering
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• v.9 no.6
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• pp.641-654
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• 2017

The KVLCC2 and its modified hull form were investigated in regular head waves using Unsteady Reynolds Averaged Navier-Stokes (URANS) methods. The modified KVLCC2 (named KWP-bow KVLCC2) is designed for reducing wave reflection from the bow. Firstly, the original KVLCC2 is studied for verification of the present code and methodology and the computed time history of total resistance and 2DOF motions (heave and pitch) for the selected two wave length conditions are directly compared with the results obtained from KRISO towing tank experiment under the identical condition. The predicted added resistance, heave and pitch motion RAOs show relatively good agreement with the experimental results. Secondly, the comparison of performance in waves between KVLCC2 and KWP-bow KVLCC2 is carried out. We confirmed that newly designed hull form shows better performances in all the range of wave length conditions through both the computation and the experiment. The present URANS method can capture the difference of performance in waves of the two hull forms without any special treatment for short wave length conditions. It can be identified that KWP-bow KVLCC2 gives about 8% of energy saving in sea state 5 condition.

• Current Optics and Photonics
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• v.4 no.1
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• pp.57-62
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• 2020

The selection of anesthetic agent is important in preclinical studies, since each agent affects the systemic hemodynamics in different ways. For that reason, we hypothesized that different anesthetic agents will result in different vaginal hemodynamic response and temperature during sexual arousal, in an animal model. To validate the hypothesis, animal experiments were performed using female rats with two anesthetic agents widely used in preclinical studies: ketamine and isoflurane. Our previously developed near-infrared-spectroscopy-based probe was used to measure the changes of oxyhemoglobin (OHb), deoxyhemoglobin (RHb), and total hemoglobin (THb) concentrations along with temperature from the animal vaginal wall. As a control, saline was administered to both isoflurane- and ketamine-anesthetized animals, and did not show any significant changes in OHb, RHb, THb, or temperature. However, an administration of apomorphine (APO, 80 ㎍/kg) induced increases of OHb (63 ± 28 μM/DPF), RHb (35 ± 20 μM/DPF), and THb (98 ± 49 μM/DPF) in ketamine-anesthetized animals, while decreases of OHb (52 ± 76 μM/DPF) and THb (38 ± 30 μM/DPF) and an increase of RHb (28 ± 51 μM/DPF) were found in isoflurane-anesthetized animals. The vaginal temperature decreased from the baseline in both ketamine-(0.42℃) and isoflurane-(1.22℃)anesthetized animals. These results confirmed our hypothesis, and suggest that a preclinical study monitoring hemodynamic responses under anesthesia should employ an appropriate anesthetic agent for the study.

• Journal of Korean Academy of Nursing
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• v.19 no.1
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• pp.63-80
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• 1989

This study was undertaken at Yonsei University Medical Center to identify the crisis responses and nursing problems of patients who had been diagnosed with cancer, and changing patterns of grieving over time periods, and to analyse the effectiveness of follow up care through home visiting nursing. This study was carried out in three stages. The 1st study data were collected from a total of 205 patients who had been diagnosed with cancer from Sept.1 to Dec. 31, 1987 using a cross-sectional method. The 2nd study data were collected three times from 30 patients with cancer at 4 weeks intervals from March 1 to June 31, 1988 using a longitudinal method. The 3rd study data were collected from two different groups from March 1 to June 31, 1988. One was an experimental group who was visited by nurses and the other one was a control group not visited by nurses. The subjects of the 3rd study consisted of 60 patients with cancer and a Quasi-experimental research design was used. The results were as follows ; 1. The patients did not experience one stage at a time among the five stages of grieing, denial anger, bargaining, depression and acceptance, as identified by Kubler Ross. They experienced a combination of stages, especially of the bargaining and the depression stages. This stages did not change with the passing of time. 2. The patients expressed more physical and socioecounomical problems than emotional problems. And they used more problem coping methods than emotional coping methods. 3. Follow up care through home visiting nursing positively influenced the patient's quality of life, especially their physical well-being and symptom control The patients responded positively to the home visiting nursing, stating that it was helpful In them. It was concluded that the development of a home visiting nursing program is needed for the effective home care of patients with cancer.

• Journal of Korean Academy of Nursing
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• v.47 no.1
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• pp.133-141
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• 2017

Purpose: The aim of this study was to identify the relationship between awareness of nutrition labeling and menstrual cycle irregularity in women from a nationally representative sample of the Korean population. Methods: A cross-sectional analysis was performed using hierarchical multi-variable logistic regression analysis models. A total of 4,324 women aged 19~54 years from the 2010~2012 Korean National Health and Nutrition Examination Survey participated in the study. The participants were classified into three groups based on self-report responses to a questionnaire about their awareness of nutrition labels: Reading, Not-Reading, and Not-Knowing Groups. Results: The Reading, Not-Reading, and Not-Knowing Groups comprised 46.4%, 44.9%, and 8.7% of the participants, respectively, and 53.6% of the participants had never used nutrition labels. In the Not-Knowing Group, irregular menstrual cycles for more than 3 months were significantly more common than women with irregular menstrual cycles for up to 3 months and women with regular menstrual cycles. Women in the Not-Knowing Group were more likely to exhibit menstrual cycle irregularity (adjusted odds ratio: 1.63, 95% confidence interval: 1.10~2.41) compared to women in the Reading Group after adjusting for age, body mass index, smoking status, alcohol intake, exercise regularity, stress, depression, suicidal ideation, metabolic syndrome, age at menarche, parity, and use of oral contraceptives. Conclusion: No awareness of nutrition labeling appears to be associated with a higher prevalence of menstrual cycle irregularity in a nationally representative group of Korean women.