보건교사의 교사효능감이 교사헌신에 미치는 영향: 전문성 지향성의 매개효과

박세진 ( Park¸ Sejin ),이주미 ( Lee¸ Jumi ) 한국아동교육학회 2021 아동교육 Vol.30 No.4

본 연구의 목적은 보건교사의 교사효능감, 전문성 지향성, 교사헌신 간 관계에서 전문성 지향성의 매개효과를 확인하기 위함이다. 연구대상은 G시에 위치한 초·중등학교에서 근무 중인 보건교사 159명이며 교사효능감, 교사헌신, 전문성 지향성 척도를 사용하여 자료를 수집하였다. 자료분석은 SPSS 21.0를 사용하여 기술분석과 상관분석을 실시하였으며 PROCESS Macro를 사용하여 교사헌신과 교사효능감의 관계에서 전문성 지향성의 매개효과의 유의성을 검증하였다. 연구 결과를 보면, 보건교사의 교사효능감과 교사헌신의 관계에서 전문성 지향성이 부분매개변인으로 영향력을 증가시키는 것으로 확인되었다. 결론적으로 보건교사의 교사헌신 향상을 위해서 교사효능감과 전문성 지향성이 중요한 변인임을 밝히는 데 의의가 있다. 나아가 보건교사의 교사효능감, 교사헌신, 전문성 지향성을 향상시킬 수 있는 여러 지원방안이 모색될 필요가 있음을 시사한다. This study was conducted to examine the mediating effect of professional orientation in the relationship between teacher efficacy and teacher commitment in health teachers. The subjects of this study were 159 health teachers working in schools located in G city. Data were collected using teacher efficacy, teacher commitment, and professional-orientation scales. SPSS 21.0 was used to conduct descriptive analysis and correlational analysis. PROCESS Macro was also conducted to verify the mediation effect of professional orientation. This study found that the relationship between health teachers' teacher efficacy and teacher commitment was partially mediated by their professional orientation. This study provided several implications and suggestions to improve health teacher's efficacy, teacher commitment and professional orientation for their professional development.

TSCOT ⁺ Thymic Epithelial Cell-Mediated Sensitive CD4 Tolerance by Direct Presentation

Ahn, Sejin,Lee, Gwanghee,Yang, Soo Jung,Lee, Deokjae,Lee, Seunghyuk,Shin, Hyo Sun,Kim, Min Cheol,Lee, Kee Nyung,Palmer, Douglas C,Theoret, Marc R,Jenkinson, Eric J,Anderson, Graham,Restifo, Nicholas P Public Library of Science 2008 PLoS biology Vol.6 No.8

<▼1><P>Although much effort has been directed at dissecting the mechanisms of central tolerance, the role of thymic stromal cells remains elusive. In order to further characterize this event, we developed a mouse model restricting LacZ to thymic stromal cotransporter (TSCOT)-expressing thymic stromal cells (TDLacZ). The thymus of this mouse contains approximately 4,300 TSCOT<SUP>+</SUP> cells, each expressing several thousand molecules of the LacZ antigen. TSCOT<SUP>+</SUP> cells express the cortical marker CDR1, CD40, CD80, CD54, and major histocompatibility complex class II (MHCII). When examining endogenous responses directed against LacZ, we observed significant tolerance. This was evidenced in a diverse T cell repertoire as measured by both a CD4 T cell proliferation assay and an antigen-specific antibody isotype analysis. This tolerance process was at least partially independent of <I>Autoimmune Regulatory Element</I> gene expression. When TDLacZ mice were crossed to a novel CD4 T cell receptor (TCR) transgenic reactive against LacZ (BgII), there was a complete deletion of double-positive thymocytes. Fetal thymic reaggregate culture of CD45- and UEA-depleted thymic stromal cells from TDLacZ and sorted TCR-bearing thymocytes excluded the possibility of cross presentation by thymic dendritic cells and medullary epithelial cells for the deletion. Overall, these results demonstrate that the introduction of a neoantigen into TSCOT-expressing cells can efficiently establish complete tolerance and suggest a possible application for the deletion of antigen-specific T cells by antigen introduction into TSCOT<SUP>+</SUP> cells.</P></▼1><▼2><P><B>Author Summary</B></P><P><B/></P><P>T cells play critical roles in the immune response. While developing in the thymus (from whence T cells and their precursors, thymocytes, derive their name), thymocytes are selected for the ability to recognize harmful antigen (positive selection), while those that respond to antigens present in their own body are eliminated (negative selection). Dogma holds that the thymus is divided into different functional compartments to ensure that these contrasting selection processes occur efficiently: the cortex is thought to be responsible for positive selection and the medulla for negative selection. In this study, we made use of a novel transgenic mouse (carrying a LacZ marker in a small fraction of cells in the cortex) to test whether the cortex is really excluded from negative selection. We were able to show that the introduced LacZ “antigen” present only in the cortical cells leads them to eliminate any LacZ-reactive T cells from the immune repertoire and leads to tolerance of the LacZ “antigen” by the body's immune system. This process is highly efficient, such that a relatively tiny number of antigen molecules present in a small fraction of the cells in the thymic cortex can singularly perform proofreading of all developing thymocytes.</P></▼2><▼3><P>A new study shows that antigen-specific negative selection of developing thymocytes is a property of thymic cortical epithelial cells, challenging the view that this process requires contact with specialized antigen-presenting cells found in the thymic medulla.</P></▼3>

Fabrication of high crystalline SnS and SnS₂ thin films, and their switching device characteristics

Choi, Hyeongsu,Lee, Jeongsu,Shin, Seokyoon,Lee, Juhyun,Lee, Seungjin,Park, Hyunwoo,Kwon, Sejin,Lee, Namgue,Bang, Minwook,Lee, Seung-Beck,Jeon, Hyeongtag IOP Pub 2018 Nanotechnology Vol.29 No.21

<P>Representative tin sulfide compounds, tin monosulfide (SnS) and tin disulfide (SnS<SUB>2</SUB>) are strong candidates for future nanoelectronic devices, based on non-toxicity, low cost, unique structures and optoelectronic properties. However, it is insufficient for synthesizing of tin sulfide thin films using vapor phase deposition method which is capable of fabricating reproducible device and securing high quality films, and their device characteristics. In this study, we obtained highly crystalline SnS thin films by atomic layer deposition and obtained highly crystalline SnS<SUB>2</SUB> thin films by phase transition of the SnS thin films. The SnS thin film was transformed into SnS<SUB>2</SUB> thin film by annealing at 450 °C for 1 h in H<SUB>2</SUB>S atmosphere. This phase transition was confirmed by x-ray diffractometer and x-ray photoelectron spectroscopy, and we studied the cause of the phase transition. We then compared the film characteristics of these two tin sulfide thin films and their switching device characteristics. SnS and SnS<SUB>2</SUB> thin films had optical bandgaps of 1.35 and 2.70 eV, and absorption coefficients of about 10<SUP>5</SUP> and 10<SUP>4</SUP> cm<SUP>−1</SUP> in the visible region, respectively. In addition, SnS and SnS<SUB>2</SUB> thin films exhibited p-type and n-type semiconductor characteristics. In the images of high resolution-transmission electron microscopy, SnS and SnS<SUB>2</SUB> directly showed a highly crystalline orthorhombic and hexagonal layered structure. The field effect transistors of SnS and SnS<SUB>2</SUB> thin films exhibited on–off drain current ratios of 8.8 and 2.1 × 10<SUP>3</SUP> and mobilities of 0.21 and 0.014 cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP>, respectively. This difference in switching device characteristics mainly depends on the carrier concentration because it contributes to off-state conductance and mobility. The major carrier concentrations of the SnS and SnS<SUB>2</SUB> thin films were 6.0?×?10<SUP>16</SUP> and 8.7?×?10<SUP>13</SUP> cm<SUP>−3</SUP>, respectively, in this experiment.</P>

Oncologic Safety of Laparoscopic Wedge Resection with Gastrotomy for Gastric Gastrointestinal Stromal Tumor: Comparison with Conventional Laparoscopic Wedge Resection

Lee, Sejin,Kim, You Na,Son, Taeil,Kim, Hyoung-Il,Cheong, Jae-Ho,Hyung, Woo Jin,Noh, Sung Hoon The Korean Gastric Cancer Association 2015 Journal of gastric cancer Vol.15 No.4

Purpose: Various laparoscopic wedge resection (LWR) techniques requiring gastrotomy for gastrointestinal stromal tumors (GISTs) of the stomach have been applied to facilitate tumor resection and preserve the remnant gastric volume. However, there is the possibility of cancer cell dissemination during these procedures. The aim of this study was to assess the oncologic safety of LWR with gastrotomy (LWR-G) compared to LWR without luminal exposure. Materials and Methods: Clinicopathologic and operative results of 193 patients who underwent LWR for gastric GIST were retrospectively analyzed from 2003 to 2013. We stratified the patients into two groups: LWR-G and LWR without gastrotomy (LWR-C). Clinicopathologic features, short-term outcomes, and long-term outcomes were compared. Results: A total of 26 patients underwent LWR-G, and 167 patients underwent LWR-C. The LWR-G group showed significantly more anterior wall-located (n=10, 38.5%), intraluminal (n=20, 76.9%), and ulcerative (n=13, 50.0%) tumors than the LWR-C group (n=33, 19.8%; n=96, 57.5%; n=46, 27.5%, respectively). Postoperative short-term outcomes did not differ between the two groups. When tumor staging was compared, no statistical difference was noted. There was no recurrence in the LWR-G group, while 2 patients in the LWR-C group experienced recurrence. The two recurrences in the LWR-C group were found in the liver and in the remnant stomach at 63 and 12 months after the operation, respectively. No gastric GIST-related death was recorded in any group during the study period. Conclusions: LWR-G for gastric GIST is an oncologically safe procedure even for masses with ulcerations.

A study on the unsteady conjugate heat transfer of hot gas valve

Lee, Kyungwook,Heo, Seonuk,Kwon, Sejin,Lee, Jongkwang Elsevier 2017 AEROSPACE SCIENCE AND TECHNOLOGY Vol.68 No.-

<P><B>Abstract</B></P> <P>Numerical simulations of a hot gas valve were conducted in this study to establish an analysis method. The far-field effect was also checked to select a computational domain. The existence of the far-field did not affect flow and temperature characteristics. The grid sensitivity was checked by varying the grid number from 25,000 to 120,000. The thrusts were similar according to the number of grid. However, differences in temperature distribution were observed.</P> <P>Three turbulence models were adopted to determine the influence of turbulence on thrust and temperature distribution: Spalart–Allmaras, RNG k – ε , and k – ω SST. The thrusts of the hot gas valve were similar in all simulation cases. However, an approximately 2% deviation in temperature distribution was observed at an operating pressure of 128 atm.</P> <P>Time step size and iteration were selected for the unsteady analysis. The analysis was conducted using only an S–A turbulent model and a valve grid. No significant difference was found. Hence, the time step size was set as 10 μs, and 50 iterations were performed. The unsteady analysis was conducted by increasing the time step size throughout the four sections considering the operating time of the hot gas valve. The time step size was increased when the quantitative result reached within 5% difference in each section. The flow, pressure, and temperature fields in the flow area reached the steady state with within 5% difference at 8 ms, 100 ms, and 5.5 s, respectively. The three fields in the flow area reached the steady state at 10 s from the operating time of the hot gas valve. However, an approximately 7% difference in temperature field was observed in the solid area. The calculation time was reduced by approximately 130 times compared to the existing calculation method.</P>

Investigation of electrospun Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3-δ-Gd_0.1Ce_0.9O_1.95 cathodes for enhanced interfacial adhesion

Lee, Sanghun,Lee, Kunho,Kang, Sungmin,Kang, Juhyun,Song, Sejin,Bae, Joongmyeon Pergamon Press 2018 International journal of hydrogen energy Vol.43 No.46

<P> Fibrous Ba<SUB>0.5</SUB>Sr<SUB>0.5</SUB>Co<SUB>0.8</SUB>Fe<SUB>0.2</SUB>O<SUB>3-δ</SUB>-Gd<SUB>0.1</SUB>Ce<SUB>0.9</SUB>O<SUB>1.95</SUB> (BSCF-GDC) composite cathodes are fabricated by a facile electrospinning method. However, the electropun BSCF-GDC cathode shows poor adhesion to a GDC electrolyte because of the high shrinkage rate of the electrospun BSCF-GDC cathode during sintering. To solve this adhesion issue, mixed BSCF fiber-GDC powder cathode is investigated. As a result, mixed BSCF fiber-GDC powder cathode with an enhanced adhesion is successfully fabricated. This improvement can be attributed to the modified microstructure with the GDC powder that joins the BSCF fibers to the GDC electrolyte at the cathode and electrolyte interface. The polarization resistance of the mixed BSCF fiber-GDC powder cathode is 0.10 Ω cm<SUP>2</SUP>, which is lower than 0.13 Ω cm<SUP>2</SUP> of conventional BSCF-GDC powder cathode at 700 °C. It is attributable to the improved oxygen gas and lattice oxygen diffusion, and the surface exchange of the mixed BSCF fiber-GDC powder cathode. The single cell with a mixed BSCF fiber-GDC powder cathode show 500 mW cm<SUP>-2</SUP> at 700 °C, which is 25% higher than conventional BSCF-GDC powder cathode. </P>

Intragenic CpG islands play important roles in bivalent chromatin assembly of developmental genes

Lee, Sun-Min,Lee, Jungwoo,Noh, Kyung-Min,Choi, Won-Young,Jeon, Sejin,Oh, Goo Taeg,Kim-Ha, Jeongsil,Jin, Yoonhee,Cho, Seung-Woo,Kim, Young-Joon National Academy of Sciences 2017 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.114 No.10

<P>CpG, 5'-C-phosphate-G-3', islands (CGIs) have long been known for their association with enhancers, silencers, and promoters, and for their epigenetic signatures. They are maintained in embryonic stem cells (ESCs) in a poised but inactive state via the formation of bivalent chromatin containing both active and repressive marks. CGIs also occur within coding sequences, where their functional role has remained obscure. Intragenic CGIs (iCGIs) are largely absent from housekeeping genes, but they are found in all genes associated with organ development and cell lineage control. In this paper, we investigated the epigenetic status of iCGIs and found that they too reside in bivalent chromatin in ESCs. Cell type-specific DNA methylation of iCGIs in differentiated cells was linked to the loss of both the H3K4me3 and H3K27me3 marks, and disruption of physical interaction with promoter regions, resulting in transcriptional activation of key regulators of differentiation such as PAXs, HOXs, and WNTs. The differential epigenetic modification of iCGIs appears to be mediated by cell type-specific transcription factors distinct from those bound by promoter, and these transcription factors may be involved in the hypermethylation of iCGIs upon cell differentiation. iCGIs thus play a key role in the cell type-specific regulation of transcription.</P>

Intracorporeal delta-shaped gastroduodenostomy during two-port distal gastrectomy

Sejin Lee,Jeong Ho Song,Sung Hyun Park,Minah Cho,Yoo Min Kim,Woo Jin Hyung,Hyoung-Il Kim 대한종양외과학회 2022 대한임상종양학회 학술대회지 Vol.2022 No.2

온도의 영향을 받는 탄소기반 나노유체의 점도 특성에 대한 연구

Sejin Lee,Jongsuk Lee,Yan Chen,Hong Liang,Sunghan Kim 대한기계학회 2022 대한기계학회 춘추학술대회 Vol.2022 No.3

Identification, prevention, and treatment of Legionella in bath facility water systems in South Korea

Lee June Hae,Lee Sejin,여명석 대한설비공학회 2023 International Journal of Air-Conditioning and Refr Vol.31 No.1

Legionella bacteria infect people via aerosol transmission. These pathogens can meaningfully affect people with weak immune systems and the older adult population. Legionella proliferate in water systems at temperatures between 25 and 45 °C, the optimum range for bath facilities. Here, we discuss how and where water systems can be contaminated by Legionella in bath facility water systems in South Korea. An epidemiological investigation of Legionella detection data from the Korea Disease Control and Prevention Agency was conducted to understand the tendencies of general outbreaks of water system types in building groups. Onsite investigations were then conducted to identify the causes of contamination in water systems in actual Legionella detection cases. According to annual Legionella detection data, the highest rate of Legionella was detected in hot bathtub water. Onsite investigations revealed that sand filter circulation systems for bathtubs are susceptible to Legionella growth. Overall, this study examined the mechanisms of buidling water systems from a building engineering perspective in order to provide valuable information for future studies and strategies to control Legionella growth in bath facility water systems.