• Journal of Ecology and Environment
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• v.38 no.2
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• pp.133-143
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• 2015

Freshwater macrophytes improve the structural heterogeneity of microhabitats in water, often providing an important habitat for zooplankton. Some studies have focused on the overall influence of macrophytes on zooplankton, but the effects of macrophyte in relation to different habitat characteristics of zooplankton (e.g., epiphytic and pelagic) have not been intensively studied. We hypothesized that different habitat structures (i.e., macrophyte habitat) would strongly affect zooplankton distribution. We investigated zooplankton density and diversity, macrophyte characteristics (dry weight and species number), and environmental parameters in 40 shallow wetlands in South Korea. Patterns in the data were analyzed using a self-organizing map (SOM), which extracts information through competitive and adaptive properties. A total of 20 variables (11 environmental parameters and 9 zooplankton groups) were patterned onto the SOM. Based on a U-matrix, 3 clusters were identified from the model. Zooplankton assemblages were positively related to macrophyte characteristics (i.e., dry weight and species number). In particular, epiphytic species (i.e., epiphytic rotifers and cladocerans) exhibited a clear relationship with macrophyte characteristics, while large biomass and greater numbers of macrophyte species supported high zooplankton assemblages. Consequently, habitat heterogeneity in the macrophyte bed was recognized as an important factor to determine zooplankton distribution, particularly in epiphytic species. The results indicate that macrophytes are critical for heterogeneity in lentic freshwater ecosystems, and the inclusion of diverse plant species in wetland construction or restoration schemes is expected to generate ecologically healthy food webs.

• Journal of Korean Society of Disaster and Security
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• v.13 no.3
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• pp.59-74
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• 2020

The purpose of this study is to explore the subjective perception of college students' Internet addiction by applying photovoice method, a participatory research method. The subjects of the study were nine university students at G University. The data were analyzed by orientation, photo collection, photo selection, contextualizing and codifying according to the general photo voice research procedure.As a result, 15 sub-categories were derived based on the meaning of Internet addiction, the effects of Internet addiction on life, and how to get out of Internet addiction. The perception of the meaning of Internet addiction was divided into five categories: 'loss of self-regulation', 'habit without exit', 'disconnection from the world', 'loss of me', and 'voluntary prison'. The effects of Internet addiction on life were 5 categories: 'health deterioration', 'social isolation', 'broken daily life', 'anonymous violence' and 'my discovery and life extension'. In terms of how to get out of internet addiction, 'self-looking', 'new hobbies', 'nearby', 'reality meetings', and 'forced blocking' were derived. It suggested the discussion about Internet addiction viewed by college students and the implications of constructing a counseling program that can help to use the Internet correctly.

• Korean Journal of Culture and Social Issue
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• v.15 no.1
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• pp.133-153
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• 2009

Two empirical studies were conducted to examine what determines the happiness of Korean adolescents. In Study 1, 155 high school students were asked to describe situations where they felt happy. Content analysis was conducted for their responses, which led to three categories, physical (economy, health and appearance), psychological (self-related responses, rest and leasure, and religion), and social one (haman relationship including family, friendship, etc, and social achievement). In Study 2, 450 high school students rated themselves on each of 88 happiness items developed through the responses obtained in Study 1. Factor analysis created 10 happiness factors labeled familial relationship, individuality, academic performance, religion, dating friends, appearance, self-discovery, economy, friendships, and psychological composure. These findings were compared with those findings about the middle-aged and the old-aged, and discussed on the developmental and cultural perspective.

• Journal of Korean Elementary Science Education
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• v.27 no.1
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• pp.42-48
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• 2008

The purpose of this study was to develop an instrument for assessing teachers' awareness of science teaching through analogy (ASTA) and to establish its validity and reliability. Based on the literatures on science teaching with analogies, we constructed 23 survey items. Face validity of the items was established using three science education experts. Through exploratory factor analysis with responses of 35 pre- and 26 inservice elementary school teachers, the instruments were constructed on four subcategories: awareness of analogies in science, use of analogy in teaching and learning, self-efficacy in science knowledge, and knowledge of analogy. The data collected from pre- and in-service elementary teachers demonstrated that overall the teachers' awareness of analogy in science was neutral, which indicated they did not have clear standpoints of science teaching through analogy. Further examination demonstrated that there was no significant difference between pre- and in-service teachers and between two genders. Moreover, there was no significant difference among teachers who preferred either didactic or discovery teaching approaches. We conclude that ASTA test would contribute assessment of teachers' awareness of analogy in science teaching while further examination of the instrument will warrant for its broader use.

• Journal of the Korean Ceramic Society
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• v.50 no.1
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• pp.1-17
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• 2013

Since their first discovery, carbon nanotubes (CNTs) have become a material central to the field of nanotechnology. Owing to their splendid physical, structural and chemical properties, they have the potential to impact a wide range of applications, including advanced ceramics, nanoelectronic devices, nanoscale sensors, solar cells, battery electrodes, and field emitters. This review summarizes the synthetic methods of preparing CNTs and focuses on the chemical vapor deposition (CVD) method, especially catalytic CVD. In order to stabilize and disperse the catalyst nanoparticles (NPs) during synthesis, zeolite was implemented as the template to support metal-containing NPs, so that both CNTs in the bulk and on a 2D substrate were successfully synthesized. Despite more challenges ahead, there is always hope for widespread ever-new applications for CNTs with the development of technology.

• Journal of Korean Academy of Nursing
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• v.39 no.2
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• pp.217-228
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• 2009

Purpose: Guided by Newman's theory of health as expanding consciousness, this study was done to explore the health experience of adolescents having depression. Methods: The researcher engaged in six to eight in-depth interviews with six adolescents. To begin the dialog, the researcher asked each participant to recount the first important memory he/ she had. All the narrative and diagram sharing between the researcher and participants were summarized according to recognized patterns and later elaborated in following interviews based on Newman's praxis methodology. Results: The significant individual pattern of early health experience was during the binding stage. At the turning point, individual patterns for participants revealed a personal journey of self-discovery and then emergence of reflecting behaviors. After the turning point, the participants changed as they evolved from the initial period of disruption and disorganization to organization at a higher level. The results suggest that adolescents who are depressive find new ways of relating to friends, family, healthcare providers, and the community by expanding their consciousness. Conclusion: Newman's praxis methodology is a good way of helping and studying adolescents with depression because it emphasizes participant-nurse/researcher partnership and pattern recognition as nursing practice.

• Journal of Korean Elementary Science Education
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• v.39 no.2
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• pp.228-242
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• 2020

The purpose of this study is to develop a student-led instructional strategy that is central to the teaching-learning process and to investigate its effects. For this study, we analyzed the learner-centered learning types (discovery learning, problem-based learning, inquiry learning) and extracted elements applicable to newly developed teaching-learning. Based on this, a student-led class strategy was established using pre-learning, teacher collaboration, small group composition, and limited open data and product presentation, and then science classes were conducted. As a result of the post-tests of the five science core competencies of the experimental group using the student-led instructional strategy and the comparative group conducting lecture-based classes, the experimental group showed higher scores than the comparative group in the scientific thinking, scientific communication, and scientific attitudes (p<.05). Based on these results, it was confirmed that the student-led class, in which the student self-adjusts the entire process of designing, exploring, and presenting learning, can help the student's scientific ability. In addition, I would like to discuss the implications of teachers' teaching-learning composition.

• Korean Journal of Social Welfare
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• v.46
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• pp.236-262
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• 2001

This discovery-oriented study explored 31 social workers' perceptions of discrepancies between explicit and implicit rules in their work places that are supposed to affect the quality of social work services, and identified eight categories of dilemmas: (a) confused accountability or purpose, (b) ambiguous principle, (c) improper authority, (d) confused role of social workers, (e) conflict between ideal and reality, (f) confused work ethics, (g) confused boundary of workers' rights, and (h) binds. These eight categories revealed the real philosophy and purposes of social work agencies, work ethics and values prevalent among social work agencies, agencies' orientation toward clients, and the conditions of social support from the society in large. Instead of searching for discrete variables as separately responsible for inefficient social work services, this approach probed malfunctioning implicit rules in a holistic context to see if inefficient or ineffective provision of social work services is a logical response to a much larger and deeper nexus. Insight into discrepant rules does not solely ensure the improvement of social work practice in the field, particularly if their identification is simply used as another opportunity to blame and avoid self-responsibility. However, such discrepancies between implicit and explicit rules are real enough to the staff workers and agency administrators that they may want to begin the dialogue of contradictory rules as a way of sanctioning discussion of previously forbidden topics. This study provided the ground-work for the dialogue.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.20 no.4
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• pp.381-388
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• 2013

Purpose: This study was done to investigate nurses' awareness of death and the meaning of life and identify factors influencing the meaning of life. Methods: Participants were 198 women nurses who had experienced the death of patients. They answered a self-administered questionnaire including demographics, awareness of death scale and meaning in life II scale. Data were analyzed using descriptive statistics, t-test, ANOVA, Scheff$\acute{e}$ test, and multiple regression (enter method). Results: The average score for awareness of death was $127.3{\pm}10.14$. This score is moderate not biased toward positive or negative. The average score for meaning of life was $130.3{\pm}9.42$ with 51% for loss steps, 45.5% for pursuit steps and 3.5% for discovery steps to the meaning of life. Factors affecting the meaning of life were religion, Buddhism (${\beta}=6.25$, p=.015) or Atheist (${\beta}=5.91$, p=.017), educational level, Master's or higher (${\beta}=16.22$, p=.003), work department, special department (${\beta}=3.49$, p=.017). Conclusions: Results of the study indicate a need to provide nursing programs that will promote nurses' spiritual and inner maturity.

• Molecules and Cells
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• v.25 no.4
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• pp.457-461
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• 2008

DNA damage checkpoint is an important self-defense mechanism for the maintenance of genome stability. Defects in DNA damage signaling and repair lead to various disorders and increase tumor incidence in humans. In the past 10 years, we have identified many components involved in the DNA damage-signaling pathway, including the product of breast cancer susceptibility gene 1 (BRCA1). Mutations in BRCA1 are associated with increased risk of breast and ovarian cancers, highlighting the importance of this DNA damage-signaling pathway in tumor suppression. While it becomes clear that BRCA1 plays a crucial role in the DNA damage responsive pathway, exactly how BRCA1 receives DNA damage signals and exerts its checkpoint function has not been fully addressed. A series of recent studies reported the discovery of many novel components involved in DNA damage-signaling pathway. These newly identified checkpoint proteins, including RNF8, RAP80 and CCDC98, work in concern in recruiting BRCA1 to DNA damage sites and thus regulate BRCA1 function in G2/M checkpoint control. This review will summarize these recent findings and provide an updated view of the regulation of BRCA1 in response to DNA damage.