• Title/Summary/Keyword: 과학실

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Macrobenthic Community Structure during Spring and Summer Season in the Environmental Conservation Area, Korea (환경보전해역에 서식하는 대형저서동물의 춘계와 하계의 군집구조)

  • Choi, Byoung-Mi;Yun, Jae Seong;Kim, Seong Gil;Kim, Seong-Soo;Choi, Ok In;Son, Min Ho;Seo, In-Soo
    • Journal of Marine Life Science
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    • v.1 no.2
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    • pp.95-108
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    • 2016
  • This study was performed to investigate the community structure of macrobenthic assemblages in the Environmental Conservation area, Korea. Benthic animals were collected by van Veen grab sampler at spring (May) and summer (August) 2009. The total species number and mean density were 195 species 5.6 m-2 and 667 individuals m-2, respectively. Polychaetes were the most dominant faunal group in species (96 species) and abundance (431 individuals m-2). The major dominant species were the polychaetes Lumbrineris longifolia (76±224 individuals m-2), Mediomastus californiensis (42±117 individuals m-2), Tharyx sp.3 (26±110 individuals m-2), the bivalvia Theora fragilis (54±78 individuals m-2) and the amphipod Eriopisella schellensis (70±146 individuals m-2). Based on the cluster and nMDS ordination analysis, macrobenthic communities were divided into three faunal groups. The first group was characterized by high abundance of the polychaeta Sternaspis scutata and the amphipod Ampelisca cyclops iyoensis, which is located by most stations of Hampyeong Bay and St. 4 of Deungnyang Bay. The second group was numerically dominated by the polychaeta Capitella capitata at St. 4 and St. 5 in Gamak Bay where was most pollutant area. Finally, the third group was dominated by the polychaetes Heteromastus filiformis, Tharyx sp.3 and the amphipod Sinocorophium sinensis. Therefore, geochemical characteristics such as the bay shape and pollution gradient may be important factors controlling of the macrobenthic community structure in Environment Conservation Area.

CDK2AP1, a Cyclin-Dependent Kinase 2-Associated Protein, Interacts with Kinesin-1 through Kinesin Superfamily Protein 5A (KIF5A) (Cyclin-dependent kinase 1 결합 단백질 CDK2AP1은 kinesin superfamily protein 5A (KIF5A)을 매개로 Kinesin-1와 결합)

  • Myoung Hun Kim;Se Young Pyo;Young Joo Jeong;Sung Woo Park;Mi Kyoung Seo;Won Hee Lee;Sang-Hwa Urm;Mooseong Kim;Jung Goo Lee;Dae-Hyun Seog
    • Journal of Life Science
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    • v.33 no.7
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    • pp.531-537
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    • 2023
  • Intracellular and axonal transport is mediated by microtubule-dependent motor proteins, such as kinesins and cytoplasmic dynein. Kinesin moves along the microtubule to the positive end of the microtubule, while dynein moves to the negative end of the microtubule. Kinesin-1 was first identified as a kinesin superfamily protein (KIF) that functions in the intracellular transport of various cargoes, including organelles, neurotransmitter receptors, and mRNA-protein complexes, through interactions between the carboxyl (C)-terminal domain and the cargo. It interacts with other cargoes, but the adapter/scaffold proteins that mediate between kinesin-1 and the cargo have yet to be fully identified. In this study, a yeast two-hybrid screen was used to identify adapter proteins that interact with the C-terminal region of KIF5A. We found an association between the C-terminal region of KIF5A and the cyclin-dependent kinase 2-associated protein 1 (CDK2AP1), originally identified in malignant hamster oral keratinocytes. CDK2AP1 bound to the C-terminal region of KIF5A and did not interact with KIF3A (the motor of kinesin-2), KIF5B, KIF5C, and kinesin light chain 1 (KLC1). The C-terminal region of CDK2AP1 is essential for its interaction with KIF5A. When co-expressed in HEK-293T cells, CDK2AP1 and kinesin-1 co-immunoprecipitated and co-localized in the cells. These results suggest that the KIF5A-CDK2AP1 interaction serves as an adapter protein connecting kinesin-1 and the cargo when kinesin-1 transports cargo in cells.

Attenuation of Oxidative Stress-Induced HepG2 Cellular Damage by Cirsiumjaponicum Root Extract (HepG2 세포에서 대계 추출물에 의한 산화적 스트레스 유발 세포 손상의 억제)

  • Da Jung Ha;Seohwi Kim;Byunwoo Son;Myungho Jin;Sungwoo Cho;Sang Hoon Hong;Yung Hyun Choi;Sang Eun Park
    • Journal of Life Science
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    • v.33 no.12
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    • pp.1002-1014
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    • 2023
  • The root of Cirsium japonicum var. maackii (Maxim.) has long been used in traditional medicine to prevent the onset and progression of various diseases and has been reported to exert a wide range of physiological effects, including antioxidant activity. However, research on its effects on hepatocytes remains scarce. This study used the human hepatocellular carcinoma HepG2 cell line to investigate the antioxidant activity of ethanol extract of C. japonicum root (EECJ) on hepatocytes. Hydrogen peroxide (H2O2) was used to mimic oxidative stress. The results showed that EECJ significantly reverted the decrease in cell viability and suppressed the release of lactate dehydrogenase in HepG2 cells treated with H2O2. Moreover, an analysis of changes in cell morphology, flow cytometry, and microtubule-associated protein light chain 3 (LC3) expression showed that EECJ significantly inhibited HepG2 cell autophagy induced by H2O2. Furthermore, it attenuated H2O2-induced apoptosis and cell cycle disruption by blocking intracellular reactive oxygen species and mitochondrial superoxide production, indicating strong antioxidant activity. EECJ also restored the decreased levels of intracellular glutathione (GSH) and enhanced the expression and activity of superoxide dismutase and GSH peroxidase in H2O2-treated HepG2 cells. Although an analysis of the components contained in EECJ and in vivo validation using animal models are needed, these findings indicate that EECJ is a promising candidate for the prevention and treatment of oxidative stress-induced liver cell damage.

Occlusal rehabilitation of post-traumatic malocclusion patient after reduction of panfacial fracture, using selective occlusal adjustment and implant prostheses on centric relation: a case report (다발성 안면 골절의 정복 후 발생한 부정교합 상태의 환자를 중심위에서 선택적 교합 조정 및 임플란트 보철수복으로 교합관계를 회복시킨 증례)

  • Dae-Kyun Kim;So-Young Park;Jung-Jin Lee;Yeon-Hee Park;Kyoung-A Kim;Jae-Min Seo
    • Journal of Dental Rehabilitation and Applied Science
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    • v.39 no.4
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    • pp.204-213
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    • 2023
  • Invasive or non-invasive reduction of fractures could be conducted as treatments of traumatic maxillofacial bone fractures. But when suboptimal reduction or malunion of maxillofacial bone fracture occurs, malocclusion could occur as a result of the lost relationship of the mandible and midface. This malocclusion is called post-traumatic malocclusion and orthognathic surgery, orthodontic treatment, selective grinding and prosthetic reconstruction are suggested as treatments for post-traumatic malocclusion after securement of stable TMJ. Stable TMJ is essential for occlusal rehabilitation to prevent occlusal change and relapse of malocclusion. Centric relation and adapted centric posture are suggested as start points of occlusal rehabilitation because they are most stable TMJ position. This case report presents a case in which post-traumatic malocclusion occurred after reduction of panfacial fracture. To rehabilitate full mouth occlusion, selective grinding and prosthetic reconstruction of implant supported fixed prostheses were conducted in centric relation and showed satisfying results in functional and occlusal aspects.

Real data-based active sonar signal synthesis method (실데이터 기반 능동 소나 신호 합성 방법론)

  • Yunsu Kim;Juho Kim;Jongwon Seok;Jungpyo Hong
    • The Journal of the Acoustical Society of Korea
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    • v.43 no.1
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    • pp.9-18
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    • 2024
  • The importance of active sonar systems is emerging due to the quietness of underwater targets and the increase in ambient noise due to the increase in maritime traffic. However, the low signal-to-noise ratio of the echo signal due to multipath propagation of the signal, various clutter, ambient noise and reverberation makes it difficult to identify underwater targets using active sonar. Attempts have been made to apply data-based methods such as machine learning or deep learning to improve the performance of underwater target recognition systems, but it is difficult to collect enough data for training due to the nature of sonar datasets. Methods based on mathematical modeling have been mainly used to compensate for insufficient active sonar data. However, methodologies based on mathematical modeling have limitations in accurately simulating complex underwater phenomena. Therefore, in this paper, we propose a sonar signal synthesis method based on a deep neural network. In order to apply the neural network model to the field of sonar signal synthesis, the proposed method appropriately corrects the attention-based encoder and decoder to the sonar signal, which is the main module of the Tacotron model mainly used in the field of speech synthesis. It is possible to synthesize a signal more similar to the actual signal by training the proposed model using the dataset collected by arranging a simulated target in an actual marine environment. In order to verify the performance of the proposed method, Perceptual evaluation of audio quality test was conducted and within score difference -2.3 was shown compared to actual signal in a total of four different environments. These results prove that the active sonar signal generated by the proposed method approximates the actual signal.

A Study on the Plant Community Structure of Carpinus Turczaninowii in Chungcheongnam-do - Case Study of Anmyondo Isl., Hwanggumsan Mt., Gayasan Mt.(Wonhyobong) and Palbongsan Mt. - (충청남도지역 소사나무림 군집구조분석 연구 - 안면도, 황금산, 가야산(원효봉) 및 팔봉산을 대상으로 -)

  • Yong-Hoon Kim;Oh-Jung Kwon;Bo-Kwang Chung;Jong-Won Song;Choong-Hyeon Oh
    • Korean Journal of Environment and Ecology
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    • v.38 no.3
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    • pp.293-309
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    • 2024
  • This study was conducted to provide basic data on the structure of the Carpinus turczaninowii community and the characteristics of the habitat environment for ex situ conservation. To identify the current ecological environment, 27 plots (each measuring 100m2) were selected for analyzing the detailed structure of plant communities in Anmyondo Isl.(Jungjangri San 14-217), Hwanggumsan Mt., Gayasan Mt.(Wonhyobong) and Palbongsan Mt.. The research methodology employed in this study was qualitative analysis. The TWINSPAN classification yielded a total of seven distinct communities. Group I represents the C. turczaninowii - Quercus mongolica community, Group II represents the C. turczaninowii - Pinus densiflora community, Group III represents the C. turczaninowii - P. densiflora community, Group IV represents the C. turczaninowii - Q. mongolica community, Group V represents the C. turczaninowii - Q. variabilis community, Group VI represents the C. turczaninowii - Prunus serrulata Lindl. var. pubescens community, and Group VII represents the C. turczaninowii - Styrax japonicus community. The species diversity ranged from 0.8056 to 1.1568, the importance value ranged from 0.1214 to 0.3024, and the similarity index ranged from 9.37% to 36.36%. Based on the correlation analysis of six environmental factors for the seven communities using RDA ordination, the results indicate that on the first axis, Altitude, Crown density, Bare rock, and Slope exhibited a positive correlation. In the C. turczaninowii - P. densiflora community (Group III) and C. turczaninowii - Q. mongolica community (Group IV), altitude, bare rock, and slope were analyzed as factors influencing vegetation distribution. In the C. turczaninowii - Q. variabilis community (Group V), C. turczaninowii - P. serrulata Lindl. var. pubescens community (Group VI), and C. turczaninowii - S. japonicus community (Group VII), crown density was analyzed as a factor influencing vegetation distribution.

A Conceptual Review of the Transaction Costs within a Distribution Channel (유통경로내의 거래비용에 대한 개념적 고찰)

  • Kwon, Young-Sik;Mun, Jang-Sil
    • Journal of Distribution Science
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    • v.10 no.2
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    • pp.29-41
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    • 2012
  • This paper undertakes a conceptual review of transaction cost to broaden the understanding of the transaction cost analysis (TCA) approach. More than 40 years have passed since Coase's fundamental insight that transaction, coordination, and contracting costs must be considered explicitly in explaining the extent of vertical integration. Coase (1937) forced economists to identify previously neglected constraints on the trading process to foster efficient intrafirm, rather than interfirm, transactions. The transaction cost approach to economic organization study regards transactions as the basic units of analysis and holds that understanding transaction cost economy is central to organizational study. The approach applies to determining efficient boundaries, as between firms and markets, and to internal transaction organization, including employment relations design. TCA, developed principally by Oliver Williamson (1975,1979,1981a) blends institutional economics, organizational theory, and contract law. Further progress in transaction costs research awaits the identification of critical dimensions in which transaction costs differ and an examination of the economizing properties of alternative institutional modes for organizing transactions. The crucial investment distinction is: To what degree are transaction-specific (non-marketable) expenses incurred? Unspecialized items pose few hazards, since buyers can turn toalternative sources, and suppliers can sell output intended for one order to other buyers. Non-marketability problems arise when specific parties' identities have important cost-bearing consequences. Transactions of this kind are labeled idiosyncratic. The summarized results of the review are as follows. First, firms' distribution decisions often prompt examination of the make-or-buy question: Should a marketing activity be performed within the organization by company employees or contracted to an external agent? Second, manufacturers introducing an industrial product to a foreign market face a difficult decision. Should the product be marketed primarily by captive agents (the company sales force and distribution division) or independent intermediaries (outside sales agents and distribution)? Third, the authors develop a theoretical extension to the basic transaction cost model by combining insights from various theories with the TCA approach. Fourth, other such extensions are likely required for the general model to be applied to different channel situations. It is naive to assume the basic model appliesacross markedly different channel contexts without modifications and extensions. Although this study contributes to scholastic research, it is limited by several factors. First, the theoretical perspective of TCA has attracted considerable recent interest in the area of marketing channels. The analysis aims to match the properties of efficient governance structures with the attributes of the transaction. Second, empirical evidence about TCA's basic propositions is sketchy. Apart from Anderson's (1985) study of the vertical integration of the selling function and John's (1984) study of opportunism by franchised dealers, virtually no marketing studies involving the constructs implicated in the analysis have been reported. We hope, therefore, that further research will clarify distinctions between the different aspects of specific assets. Another important line of future research is the integration of efficiency-oriented TCA with organizational approaches that emphasize specific assets' conceptual definition and industry structure. Finally, research of transaction costs, uncertainty, opportunism, and switching costs is critical to future study.

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Clinical Convergence Angle of Prepared Tooth for full Veneer Crowns (전부 피개관의 치아 형성 시 축면 경사각에 대한 조사)

  • Kim, Sung-Jin;Pae, Ah-Ran;Woo, Yi-Hyung;Kim, Hyeong-Seob
    • Journal of Dental Rehabilitation and Applied Science
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    • v.26 no.1
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    • pp.21-32
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    • 2010
  • The convergence angle of a prepared tooth is a very important factor in the retention and resistance of a crown restoration. But various intraoral environments and clinician's techniques make it difficult to obtain the ideal inclination. Therefore, in this study, clinical convergence angle of a prepared tooth was investigated. The data was collected from the patient models of prosthodontic residents and the patient models of general practitioners. The images of mesiodistal and buccolingual surfaces were taken with a digital camera to evaluate the convergence angle on 'ImageJ' program. The images were classified according to the criteria (1. Clinician group, 2. Position in the dental arch, 3. The purpose of abutment preparation)and then analyzed. The mean convergence angle of a prepared tooth for Korean clinicians was $15.02^{\circ}$ (${\pm}10.13^{\circ}$). 1. It was significant in the convergence angle between the general practitioner group and the prosthodontic resident group(p<0.05). 2. It was significant between the mesiodistal and buccolingual surface in the the prosthodontic resident group(p<0.05). 3. For the general practitioner group, it was significant when anteriors and premolars were compared with molars(p<0.05). For the prosthodontic resident group, it was significant when anteriors and premolars were compared with molars (p<0.05). 4. When divided into upper and lower arches, for the general practitioner group, it showed significant difference in the buccolingual aspect(p<0.05). Also in the prosthodontic resident group, it showed significant difference in the buccolingual aspect(p<0.05). 5. Dividing left and right sides of the arches, there was no significant difference in the general practitioner group and the prosthodontic resident group(p>0.05). 6. In the general practitioner group, it was significant in the mesiodistal axial convergence angle of single crown abutment and 3 unit bridge abutment(p<0.05). In the prosthodontic resident group, it was significant in the mesiodistal and overall axial convergence angle of single crown abutment and 3 unit bridge abutment(p<0.05). Clinical convergence angle of prepared tooth in Korea was included in agreement with other studies investigating convergence angle that ranged from 10 to 22 degrees, achieved in clinical practice.

Changes of Housing in the FCS Curricular from the 1st to 2009 Revised of Secondary School (중등학교 가정과 교육과정의 주생활 영역 내용 변화 - 1차 교육과정부터 2009 개정 교육과정을 대상으로 -)

  • Heo, YoungSun;Kim, NamEun;Choi, MinJi;Baek, MinKyung;Gwak, SeonJeong;Cho, JaeSoon
    • Journal of Korean Home Economics Education Association
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    • v.25 no.1
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    • pp.95-118
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    • 2013
  • The purpose of this study was to analyze the contents of housing related to characters, objectives, and contents of FCS curricular from the 1st to 2009 revised curriculum of secondary school. The data were downloaded from the NCIC homepage(http://www.ncic.re.kr/2012. 04. 08) from the 1st(1955. 08) to 2009 revised curriculum(2012. 03) of secondary school. After examining the characters and objectives of each curriculum, contents of housing was analyzed by units and context elements of middle and high school separately. The titles of the subject, the objectives, the instructions, the leaning spheres, weekly hours, grade and gender of candidates, the emphasis of the instruction, etc. have been changed through the curriculum revision. The 6th curriculum was the main period to open to both genders, the $7^{th}$ was the period to combine with technology, the 2007 version was to change the structure of contents of home economics, and the 2009 version switched technology home economics from mandatory to optional in high school. The character of the courses was presented at the 1st curriculum, but it was left out from the $2^{nd}$ to $5^{th}$ curriculum. From the $6^{th}$ curriculum, the characters were separately given to middle and high school. The character of housing area started to appear only in high school home economics from the $7^{th}$ curriculum. The course objectives were described in all curriculum of both middle and high school. This applies to housing area as well. The course objectives have been modified in order to reflect value changes due to social issues. During each curriculum, contents of housing continued to change in context, course load, and candidates. Reflection of housing trends and social needs were the main causes of the change. 2009 version emphasizes on eco-life and sense of community.

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A study of Spiritual Well-Being in Nursing Students (간호대학생의 영적안녕에 관한 연구)

  • Lee, Yeong-Eun;Park, Hye-Seon;Gang, Yang-Hui
    • Korean Journal of Hospice Care
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    • v.7 no.1
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    • pp.5-14
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    • 2007
  • Objective : This study was done to identify the status of Spiritual Well-Being in Nursing Students and to investigate the correlation between related various characteristics and Spiritual Well-Being and to provide baseline data for ride school-life and development of Spiritual-education program for nursing students. Method : The data was collected from 188 christian Nursing students by using questionary method. they are all all agreed to participate in this study. Their Spiritual Well-Being were measured using Spiritual Well-Being scale developed by Paloutzian & Ellison(1983) and translated by Choi(1990) and reversed by Kang(1996). Results : The data was analyzed by using SPSS/PC+12.0. The summary of results were as follows; 1. The mean score of Spiritual Well-Being were $63.95\pm10.256$(range from 20-80) 2. There were significant differences between the grade(F=6.101, p= .001), type of religion(F= 17.703, p= .000), In Christian, the level of devotee(F=8.194, p= .000), duration of church attendance(F=7.947, p= .000), regular attendance of chapel(F=4.242, p= .000), regular reading(study) of Bible and prayer (F=5.863, p= .001=0). perceived personal encounter with Jesus(F=4.160, p= .000), religion of parent(F=9.320, p= .000), perceived attitude of parenting(F=4.146, p= .000), hope to admit/transfer to other course or not(F=-2.050, p= .050). Conclusion : Our results were valuable to provide basic guidelines for ride school-life and for the development of Spiritual-education program for Nursing students.

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