• Molecules and Cells
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• v.43 no.1
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• pp.58-65
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• 2020

Fat mass and obesity-associated (FTO) gene helps to regulate energy homeostasis in mammals by controlling energy expenditure. In addition, FTO functions in the regulation of obesity and adipogenic differentiation; however, a role in osteogenic differentiation is unknown. This study investigated the effects of FTO on osteogenic differentiation of C3H10T1/2 cells and the underlying mechanism. Expression of osteogenic and endoplasmic reticulum (ER) stress markers were characterized by reverse-transcriptase polymerase chain reaction and western blotting. Alkaline phosphatase (ALP) staining was performed to assess ALP activity. BMP2 treatment increased mRNA expression of osteogenic genes and FTO. Overexpression of FTO increased expression of the osteogenic genes distal-less homeobox5 (Dlx5) and runt-related transcription factor 2 (Runx2). Activation of adenosine monophosphate-activated protein kinase (AMPK) increased FTO expression, and there was a positive feedback loop between FTO and p-AMPK. p-AMPK and FTO induced mild ER stress; however, tunicamycin-induced severe ER stress suppressed FTO expression and AMPK activation. In summary, FTO induces osteogenic differentiation of C3H10T1/2 cells upon BMP2 treatment by inducing mild ER stress via a positive feedback loop with p-AMPK. FTO expression and AMPK activation induce mild ER stress. By contrast, severe ER stress inhibits osteogenic differentiation by suppressing FTO expression and AMPK activation.

• Journal of Digital Convergence
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• v.19 no.9
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• pp.1-8
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• 2021

The purpose of this study is to identify the influence of users' satisfaction with the Automatic Writing Evaluation(AWE) on learners' sense of learning achievement through self efficacy in English writing class. AWE is a tool that automatically provides feedback on writing outputs by AI technology. College students were asked to write essays for each topic and use AWE to get feedback on their drafts, and finally revise them referring to the feedback. A questionnaire survey was conducted for the data collection. The data was analyzed using SPSS, and smart PLS-SEM along with bootstrapping techniques, The results of the study reveal the followings: 1) the convenience and usefulness of AWE had a positive effect on the willingness to reuse it; 2) the satisfaction with AWE had a positive effect on self-efficacy; 3) self-efficacy had a positive effect on learning achievement in terms of emotional and linguistic aspects. With the development of the 4th industry and A.I. technology, it is recommended to introduce new materials or programs such as AWE in English education.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.550-555
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• 2007

This paper is concerned with the active vibration control of building structure by means of the active tuned mass damper and the modified positive position feedback controller. To this end, one-degree-of-freedom spring-mass-damper system equipped with ATMD is considered. The stability condition for the addressed system when applying the proposed PPF controller is derived by Routh-Hurwitz stability criterion. The stability condition shows that the modified PPF controller is absolutely stable if the controller gain is positive, so that the modified PPF controller can be used without difficulty. Theoretical study shows that the modified PPF controller can effectively suppress vibrations as the original PPF controller does in smart structure applications. To investigate the validity of the modified PPF controller, a simple experimental structure with an ATMD system driven by DC motor was built. The modified PPF control algorithm was implemented on Atmel 128 microcontroller. The experimental result shows that the modified PPF controller can also suppress vibrations for the real structure.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.2
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• pp.224-230
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• 2008

This paper is concerned with the active vibration control of building structure by means of the active tuned mass damper and the modified positive position feedback controller. To this end, one-degree-of-freedom spring-mass-damper system equipped with ATMD is considered. The stability condition for the addressed system when applying the proposed PPF controller is derived by Routh-Hurwitz stability criterion. The stability condition shows that the modified PPF controller is absolutely stable if the controller gain is positive. so that the modified PPF controller can be used without difficulty. Theoretical study shows that the modified PPF controller can effectively suppress vibrations as the original PPF controller does in smart structure applications. To investigate the validity of the modified PPF controller, a simple experimental structure with an ATMD system driven by DC motor was built. The modified PPF control algorithm was implemented on Atmel 128 microcontroller. The experimental result shows that the modified PPF controller can also suppress vibrations for the real structure.

• Biomolecules & Therapeutics
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• v.23 no.4
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• pp.320-326
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• 2015

The clinical benefits of oncogenic BRAF inhibitor therapies are limited by the emergence of drug resistance. In this study, we investigated the role of a negative regulator of the MAPK pathway, Spry2, in acquired resistance using BRAF inhibitor-resistant derivatives of the BRAF-V600E melanoma (A375P/Mdr). Real-time RT-PCR analysis indicated that the expression of Spry2 was higher in A375P cells harboring the BRAF V600E mutation compared with wild-type BRAF-bearing cells (SK-MEL-2) that are resistant to BRAF inhibitors. This result suggests the ability of BRAF V600E to evade feedback suppression in cell lines with BRAF V600E mutations despite high Spry2 expression. Most interestingly, Spry2 exhibited strongly reduced expression in A375P/Mdr cells with acquired resistance to BRAF inhibitors. Furthermore, the overexpression of Spry2 partially restored sensitivity to the BRAF inhibitor PLX4720 in two BRAF inhibitor-resistant cells, indicating a positive role for Spry2 in the growth inhibition induced by BRAF inhibitors. On the other hand, long-term treatment with PLX4720 induced pERK reactivation following BRAF inhibition in A375P cells, indicating that negative feedback including Spry2 may be bypassed in BRAF mutant melanoma cells. In addition, the siRNA-mediated knockdown of Raf-1 attenuated the rebound activation of ERK stimulated by PLX4720 in A375P cells, strongly suggesting the positive role of Raf-1 kinase in ERK activation in response to BRAF inhibition. Taken together, these data suggest that RAF signaling may be released from negative feedback inhibition through interacting with Spry2, leading to ERK rebound and, consequently, the induction of acquired resistance to BRAF inhibitors.

• Journal of Korean Elementary Science Education
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• v.24 no.2
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• pp.111-122
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• 2005

The goal of this study was to investigate the differences in the effect of feedback from different providers on elementary school students' science achievement and to examine the responses of the students regarding the feedback. Three 6th grade classes were chosen to be assigned as experimental group 1, experimental group 2, and control group, respectively. In experimental group 1, the teacher provided feedback with students concerning the formative evaluations which were conducted periodically. Experimental group 2 was the one in which students were organized into small groups to compose and exchange feedback with one another. No feedback was of offered to students in the control group. The results of the science achievement test indicated ,that the provision of feedback by the teacher resulted in more gains in student academic achievement. The interviews with students revealed that the learners made positive responses to the feedback provided by the teacher while they showed negative attitudes toward the feedback exchange among students. There were also differences in student responses to feedback between high and low achievers in science. Implications for science lessons and science education research were presented and discussed.

• Educational Technology International
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• v.6 no.2
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• pp.23-41
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• 2005

One of the main factors that determine the quality of instruction is the teaching ability of the instructor administering the class. To evaluate teaching ability, methods such as peer review, student feedback, and teaching portfolio can be used. Among these, because feedback from the students is directly associated with how well the students feel they have learned, it is essential to improving instruction and teaching ability. The principal aim of instruction evaluation lies in the evaluation of instructor's qualification and the improvement of instruction quality by enhancing professionalism. However, the mandatory instruction evaluations currently being carried out at the term's end in universities today have limitations in improving instruction in terms of its evaluation items and times. To improve the quality of instruction and raise teaching abilities, instruction evaluations should not stop at simply being carried out but also be utilized as useful data for students and teachers. In other words, they need to be used to develop teaching and improve instruction for teachers, and consequently, should also exert a positive influence on students' scholastic achievements and learning ability. The most important thing in evaluation is the acquisition of accurate information and how to utilize it to improve instruction. The online instruction diagnosis item pool is a more realistic feedback device developed to improve instruction quality. The instruction diagnosis item pool is a cafeteria-like collection of hundreds of feedback questions provided to enable instructors to diagnose their instruction through self-diagnosis or students' feedback, and the instructors can directly select the questions that are appropriate to the special characteristics of their instruction voluntarily make use of them whenever they are needed. The current study, in order to find out if the online instruction diagnosis item pool is truly useful in reforming and improving instruction, conducted pre and post tests using 256 undergraduate students from Y university as subjects, and studied the effects of student feedback on instructions. Results showed that the implementation of instruction diagnosis improved students' responsibility regarding their classes, and students had positive opinions regarding the usefulness of online instruction diagnosis item pool in instruction evaluation. Also, after instruction diagnosis, analyzing the results through consultations with education development specialists, and then establishing and carrying out instruction reforms were shown to be more effective. In order to utilize the instruction diagnostic system more effectively, from planning the execution of instruction diagnosis to analyzing the results, consulting, and deciding how those results could be utilized to instruction, a systematic strategy is needed. In addition, professors and students need to develop a more active sense of ownership in order to elevate the level of their instruction.

• Journal of agricultural medicine and community health
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• v.23 no.1
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• pp.91-108
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• 1998

This study was conducted to use the feedback of health personnel to improve the Visiting Health Service. The data was collected from 471 Home Health Workers serving 24 local health organizations in the Kyung-Pook province. 62.5% of the respondents were men under thirty-nine years of age. 92.8% of the respondents are married. 47.1% had degrees from junior colleges. It was ascertained 52.7% of the workers visited their patients six to twelve times within a six month period. And one to three patients were visited per day by one worker. Workers of older age, higher job position, and more experience were more positive in their feedback about the program. In addition, local health center employees, including nurses, were more positive about the program. Younger workers with a higher level of education, less experience, and lower job position had more insight into the problems of the program. Deeper insight into these problems led to a more negative conception of the program. Older workers with higher ranking jobs were found to be most competent. in their jobs. Workers at the main health center were assessed higher than the workers at the health sub-center or the primary health post. In addison nurses at all centers were found to be slightly more competent than the nurses' aide. The primary health post established the highest degree of patient satisfaction. It was discovered that the more positive the workers felt about the program, the higher their patient satisfaction feedback. There was a positive correlation between management assessment and patient satisfaction. This means that better program management was found to produce higher patient satisfaction. Workers feel being more educated about patient management would lead to better service. However, they take no action to produce these results. Where the problems of the system are most commented upon, the need for further education is greatest. Through multiple regression analyses it is apparent that the assessment of patient management is the greatest variable affecting patient satisfaction of patients is dependent on the management by the visiting health worker. Therefore, the development of the visiting health program is highly dependant on the feedback of those workers with a negative conception of the program. So the development of programs, motivation, education and training must be established. These works would lead to active participation by visiting health workers in the improvement of the Visiting health program.

• Korean System Dynamics Review
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• v.13 no.1
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• pp.113-131
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• 2012

Applying social network analysis techniques, this study examines complex system characteristics of industry-university joint research R&D networks. In specific, it focuses on whether these R&D networks comply with the power law, whose system typically presents the-rich-get-richer and the-poor-get-poor patterns. The basic data come from 7,751 industry-university joint research projects, all of which were carried out by Daejeon, Chungbuk, and Chungnam-based universities from January 2005 to October 2008. The empirical results reveal that the R&D networks abide by the power law. That is, a handful of business units and universities command an overwhelming majority in the joint links, indicating positive feedback dominance within the system.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.688-691
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• 1997

This paper presents an $H^{\infty}$ controller design method for linear time-invariant systems with delayed state and control. Using the second method of Lyapunov, the stability for delayed systems is discussed. For delayed systems, we derive a sufficient condition of the bounded real lemma(BRL) which is similar to BRL for nondelayed systems. And the sufficient conditions for the existence of an output feedback $H^{\infty}$ controller of any order are given in terms of three linear matrix inequalities(LMls). Futhermore, we briefly explain how to construct such controllers from the positive definite solutions of their LMIs and give a simple example to illustrate the validity of the proposed design procedure.e.