• The Journal of Korean Society for School & Community Health Education
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• v.20 no.2
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• pp.1-12
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• 2019

Objectives: The purpose of this study is to understand the factors affecting the dual smoking experience of conventional and heat-not-burn tobacco among adolescents with smoking experience. Methods: The study selected 8,691 people with experience in smoking. Data analysis used SPSS 25.0. Logistic regression was performed to identify the factors affecting the dual smoking experience. Results: In this study, the dual smoking experience rate of conventional and heat-not-burn tobacco was 16.3%. The dual smoking experience rate was 5.09 times higher than the number of smokers among friends. The lower the smoking age, the higher the smoking rate, and the longer the smoking days, the higher the dual smoking rate of heat-not-burn cigarettes. Conclusion: We need a peer-to-peer group arbitration program rather than a separate anti-smoking arbitration program for smokers.

• The Journal of Korean Physical Therapy
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• v.32 no.6
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• pp.383-387
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• 2020

Purpose: The purpose of the present study was to investigate the effects of a simultaneous dual-task and horse-riding simulator (HRS) training regime on pulmonary function and flexibility. Methods: Sixteen subjects were recruited and randomly allocated to two groups: a dual-task (DT) (n=8) or a single-task (ST) (n=8) training group. Flexibility and pulmonary function were assessed before and after HRS training. Both groups underwent HRS training for 4 weeks, 3 times/week in 15-minute training sessions. The ST group underwent HRS training and the DT group underwent dual-task HRS training, which consisted of throwing and catching a ball and ring catching while HRS training. Results: Training significantly increased flexibility and FVC (forced vital capacity) and FEV1 (forced expiratory volume in 1 second) in both groups (p<0.05), but FEV1/FVC and PEF (peak expiratory flow) were not significantly different after training in both groups (p>0.05). After the training, flexibility and FVC in the DT group were significantly greater than in the ST group (p<0.05), but FEV1, FEV1/FVC, and PEF were not significantly different (p>0.05). Conclusion: Simultaneous dual-task and HRS motor training improved flexibility, FVC, and FEV1, and our comparative analysis suggests that dual-task HRS training improved flexibility and FVC more than single-task training.

• Biomedical Science Letters
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• v.27 no.1
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• pp.1-11
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• 2021

Cancer stem cells, which are known to drive tumor formation and maintenance, are a major obstacle in the effective treatment of various types of cancer. Trans-membrane glycoprotein mucin 1 antigen and cell surface glycogen CD44 antigen are well-known surface markers of breast cancer cells and breast cancer stem cells, respectively. To effectively treat cancer cells and cancer stem cells, we developed a new drug-encapsulating liposome conjugated with dual-DNA aptamers specific to the surface markers of breast cancer cells and their cancer stem cells. These two aptamer (Apt)-targeted liposomes, which were prepared to encapsulate doxorubicin (Dox), were named "Dual-Apt-Dox". Dual-Apt-Dox is significantly more cytotoxic to both cancer stem cells and cancer cells compared to liposomes lacking the aptamers. Furthermore, we demonstrated the inhibitory efficacy of Dual-Apt-Dox against the experimental lung metastasis of breast cancer stem cells and cancer cells in athymic nude mice. We also showed the potent antitumor effects of dual-aptamer-conjugated liposome systems by targeting cancer cells as well as cancer stem cells. Thus, our data indicate that dual-aptamer-conjugated liposome systems can prove to be effective drug delivery vehicles for breast cancer therapy.

• Journal of The Korean Society of Integrative Medicine
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• v.8 no.4
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• pp.59-66
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• 2020

Purpose : This study aimed to present normative data for older Korean adults completing the Yonsei dual task cognitive screening test (Y-DuCog) and identify changes in cognitive function on the Montreal Cognitive Assessment - Korean (MoCA-K) with age. Methods : From May 2019 to August 2019, 195 healthy adults aged ≥60 years participated in this study. All participants completed the Y-DuCog to assess their dual-task performance and the MoCA-K to assess their cognitive function. Participants were divided into three groups based on their age: 60~69 years, 70~79 years, and ≥80 years. Results : The results of the Y-DuCog showed that dual-task performance time, effect, and correct response rate decreased significantly with age (p<.001). Scores from the three groups showed differences on all items (p<.001). Cognitive function on the MoCA-K also decreased significantly with age (mean score ± standard deviation [SD]; 27.33 ± 2.61 in subjects aged 60~69 years; 24.82 ± 3.20 in subjects aged 70~79 years; and 22.10 ± 4.91 in subjects aged ≥80 years; p<.001). Conclusions : Occupational therapists should be aware of the decline in cognitive function and dual-task performance time, effect, and correct response rate in older adults and consider interventions to treat this decline. Further studies are needed with larger groups of participants to examine factors, such as sex and education, that may impact dual-task performance and cognitive function.

• Asia-Pacific Journal of Business
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• v.11 no.2
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• pp.45-60
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• 2020

Purpose - This study examines the impact of company ownership nature and of the dual role of CEO and board chair on R & D investment intensity, as well as the moderating effect of this dual role. Most previous research focused on the impact of the dual role of CEO and board chair on firm performance. Design/methodology/approach - This study uses A-share companies listed on the Shenzhen and Shanghai stock exchanges in China from 2008 to 2017. The univariate and the multivariate regression analysis were hired In order to analyze the data. Findings - The results show that there is a significant negative relationship between state-owned companies and R & D investment intensity. In addition, there is a significant positive relationship between the dual role and R & D investment intensity. The effect of state ownership on R & D investment intensity is more negative when CEO-board chair duality exists. This means that in case of state-owned companies, if CEO serves as the board chair, the propensity to invest in R&D is further reduced. Research implications or Originality - This is a pioneering study that considers the joint effect of state-owned companies and dual role on R & D investment intensity in the Chinese economy.

• Journal of Convergence for Information Technology
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• v.11 no.4
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• pp.161-167
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• 2021

This study was conducted to identify the relationship between the dual task performance and driving behavior of the elderly driver in order to identify whether the dual task can be utilized as a test to screen the driving ability of the elderly driver. We surveyed general information and driving-related information for 32 normal elderly drivers, and evaluated Y-DuCog(Yonsei-Dual task Cognitive screening) and the K-DBQ (Korean-Driving Behavior Questionnaire). As a result of the study, the performance of the dual task using the pegboard task and the animal name speaking showed a significant correlation with the score of the violation domain of K-DBQ. With this study, it was possible to confirm the possibility as a test for discrimination of driving ability.

• PNF and Movement
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• v.20 no.2
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• pp.243-251
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• 2022

Purpose: This study aimed to compare the effects of aquatic and land dual-task training on balance, gait, and depression in chronic stroke patients. Methods: A total of 24 patients diagnosed with chronic stroke were the subjects. They were assigned to either the experimental group (n = 12) or the control group (n = 12). The experimental group performed aquatic dual-task training, while the control group performed land dual-task training. The aquatic and land dual-task training sessions were conducted once a day for 30 min, 5 days per week, for 6 weeks. Balance was measured using the Berg balance scale. Gait was measured using the Timed Up and Go Test. The Beck's Depression Inventory was used to measure depression. Results: Both the experimental and control groups showed significant differences in balance, gait, and depression after the intervention (p < 0.05) in the within-group comparisons. It was found that the experimental group showed more significant differences in balance, gait, and depression than the control group (p < 0.05) when the two groups were compared. Conclusion: It can be concluded that aquatic dual-task training effectively improved the balance ability, gait ability, and chronic stroke patients' depression based on these results.

• Journal of Practical Engineering Education
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• v.5 no.2
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• pp.139-149
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• 2013

In this paper, we proposed a new Korean Dual system, K-Dual System, and discussed the concepts and details about three sub-models of the system, IPP, W3 and corporate university models. Propose K-Dual system is a new and unique educational model that combines academic study and industrial work in order to solve the various problems of existing work-study parallel educational systems in Korea. K-Dual System has two tracks, Academic and Vocational tracks. Academic track has a long-term field experience training program, IPP program. On the other hands, Vocational track can be divided into two sub-models and those are $W^3$ and corporate university. Finally, we summarized several key points for the successful setup and operation of K-Dual system.

• Journal of applied mathematics & informatics
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• v.25 no.1_2
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• pp.505-511
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• 2007

Recently, the equivalent relations between a symmetric dual problem and a matrix game B(x, y) were given in [6: D.S. Kim and K. Noh, J. Math. Anal. Appl. 298(2004), 1-13]. Using more simpler form of B(x, y) than one in [6], we establish the equivalence relations between a symmetric dual problem and a matrix game, and then give a numerical example illustrating our equivalence results.

• Bulletin of the Korean Mathematical Society
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• v.39 no.1
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• pp.133-140
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• 2002

On compact complex hyperbolic manifolds of complex dimension two, we show that the dimension of the space of infinitesimal deformations of self-dual conformal structures is smaller than that of the deformation obstruction space and that every self-dual metric with covariantly constant Ricci tensor must be a standard one upto rescalings and diffeomorphisms.