본 연구는 인성그림책을 활용한 표상활동이 만 2세 영아의 기본생활습 관 형성과 사회정서발달에 미치는 효과를 파악하기 위한 목적으로 실시 하였다. 이를 위하여 C도 A시 어린이집 재원중인 만 2세 영아 실험집단 15명, 통제집단 15명 총 30명을 대상으로, 실험집단에 총 12주(매주 4 일, 매회 1시간 20분) 동안 인성그림책을 활용한 표상활동을 실행하였다. 연구기간은 실험집단(15명)과 통제집단(15명)에게 2018년 8월 20일부터 11월 9일에 걸쳐 조사를 실시하였고, 분석방법은 비동일 통제집단 전후 비교조사로 사전-사후 검증을 위해 독립표본 t 검증, 대응표본 t 검증을 실 시하여 표상활동 프로그램의 효과를 측정하였다. 연구결과, 인성그림책을 활용한 표상활동은 만 2세 영아의 기본생활습관 형성과 사회정서발달에 긍정적인 효과가 있는 것으로 나타났다. 이러한 연구결과를 토대로 만 2 세 영아의 기본생활습관 형성과 사회정서발달 향상을 위한 보육현장에서 의 실천방안을 논의하였다.

Hot section components of gas turbines are exposed to a high operating temperature environment. To protect these components, thermal barrier coatings (TBC) are applied to their surfaces. Yttria-stabilized zirconia (YSZ), which is widely used as a TBC material, faces limitations at temperatures above 1200 °C. To mitigate these issues, research has focused on adding lanthanide rare earth oxides and tetravalent oxides to prevent the phase-transformation of the monoclinic phase in zirconia. This study investigated the effects of varying TiO2 content in Nd2O3 and Yb2O3 co-doped YSZ composites. Increasing TiO2 content effectively suppressed formation of the monoclinic phase and increased the thermal degradation resistance compared to YSZ in environments over 1200 °C. These findings will aid in developing more thermally stable and efficient TBC materials for application in high-temperature environments.

테트로도톡신(tetrodotoxin, TTX)은 강력한 해양생물 유 래 신경독소로, 수산물 내 TTX를 검출하기 위해 기존에 주로 사용되는 mouse bioassay (MBA)와 LC-MS/MS 기법 은 낮은 검출한계와 동물 윤리 문제 등의 한계가 있어 이 를 대체할 새로운 시험법 개발이 필요합니다. Neuro-2a assay는 대표적인 세포기반 대체 시험법으로, 이 방법은 마우스 신경모세포인 Neuro-2a 세포주에 ouabain (O)과 veratridine (V)을 처리하여 과도한 Na+ 유입으로 인한 세 포 사멸을 유도한 후, Na+ 채널 억제제인 TTX가 Na+ 유 입을 차단해 세포를 보호하는 원리를 이용해 TTX를 정량 합니다. 본 연구에서는 Neuro-2a assay를 국내 실험실 환경에 적용하기 위해 TTX 처리 조건과 O/V 농도 등의 매 개변수를 최적화하였습니다. 그 결과, 최적 O/V 농도로 600/60 μM를 설정하였으며, S자형 용량-반응 곡선이 도출 되는 8가지 농도(50-0.195 ng/mL)를 확인하였습니다. 또한, 24번의 반복 실험을 통해 데이터의 신뢰도를 평가할 수 있는 6가지 data criteria를 확립하였으며, 이 중 EC50 값 은 약 3.824-1.268 ng/mL로 나타났습니다. 실험실 간 변동 성 비교 결과, COV+와 Bottom OD값을 제외한 모든 품 질 관리 기준(quality control criteria)과 데이터 기준(data criteria)의 변동계수(CVs)는 1.31-14.92%로 도출되어, 실험 의 적정성과 재현성이 확인되었습니다. 본 연구는 국내에 서 활용 가능한 TTX 검출용 Neuro-2a assay의 최적 조 건과 신뢰성을 평가할 수 있는 quality control criteria와 data criteria를 제시하였습니다. 아울러, TTX뿐만 아니라 유사체인 4,9-anhydroTTX에 대한 TEF 값을 0.2098로 산 출하여, TTX뿐 아니라 다양한 유사체의 검출이 가능함 을 확인하였습니다. 향후, 본 시험법은 국내 수산물 내 TTX 검출을 위한 MBA 대체법으로 활용될 것으로 기대 됩니다.

Mo-ODS alloys have excellent mechanical properties, including an improved recrystallization temperature, greater strength due to dispersed oxides, and the ability to suppress grain growth at high temperatures. In ODS alloys, the dispersed Y2O3 and added Ti form Y-Ti-O complex oxides, producing finer particles than those in the initial Y2O3. The complex oxides increase high-temperature stability and improve the mechanical properties of the alloy. In particular, the use of TiH2 powder, which is more brittle than conventional Ti, can enable the distribution of finer oxides than is possible with conventional Ti powder during milling. Moreover, dehydrogenation leads to a more refined powder size in the reduction process. This study investigated the refinement of Yi2Ti2O7 in a nano Mo-ODS alloy using TiH2. The alloy compositions were determined to be Mo-0.5Ti-0.5Yi2O3 and Mo-1.0Ti-0.5Yi2Oi2. The nano Mo-ODS alloys were fabricated using Ti and TiH2 to explore the effects of adding different forms of Ti. The sintered specimens were analyzed through X-ray diffraction for phase analysis, and the microstructure of the alloys was analyzed using scanning electron microscopy and transmission electron microscopy. Vickers hardness tests were conducted to determine the effect of the form of Ti added on the mechanical properties, and it was found that using TiHi2 effectively improved the mechanical properties.

The present study was conducted to investigate effects of rabbit meat extract on energy metabolism and muscle differentiation in C2C12 myotubes. Water extract of rabbit meat (10, 50, 100, and 200 μg/ml) was used to treat differentiated C2C12 cells. Reverse transcriptase polymerase chain reaction (RT-PCR) and western blot analysis were used to determine mRNA or protein levels of energy metabolism-related genes. Total adenosine triphosphate (ATP) content was also measured. Treatment with rabbit meat extract significantly increased expression levels of muscle differentiation markers (myogenin and myosin heavy chain) and mitochondrial biogenesis regulators (PGC1α, NRF1, and TFAM) in C2C12 myotubes compared to non-treated control. Additionally, rabbit meat extract activated phosphorylation of AMPK and acetyl-coA carboxylase (ACC). Rabbit meat extract significantly increased ATP contents in myotubes. These results suggest that rabbit meat extract has the potential to improve energy metabolism in skeletal muscles.

Hydrogen peroxide (H2O2) is widely used in bleaching treatments in the pulp and paper industry, in wastewater treatment, and as a food additive. However, H2O2 solutions are unstable and decompose slowly when subjected to external factors such as light, high temperatures, or metal compounds. Therefore, a simple and reliable method to measure the concentration of H2O2 is required for its proper use in various applications. We determined the concentration of an H2O2 solution by measurement at a single wavelength (249 nm) without any reagents or complex analytical procedures. In the present work, the measurable concentration of H2O2 was as low as 0.015 wt% (4.41 mM) and as high as 0.300 wt% (88.2 mM), with high linearity (99.99% at 249 nm) between the concentration of H2O2 and the optical density (OD) values. In addition, the method could be used to measure the concentration of H2O2 in a peracetic acid solution without interference from acetic acid and peracetate ion.

이 실험에서는 α-Al2O3 지지체 위에 진공 코팅(vacuum coating)과 딥 코팅(dip-coating) 기법을 사용하여 GO/γ -Al2O3 중간층을 형성하였고, 무전해도금 방식을 통해 Pd-Ag 수소 분리막을 제작하였다. Pd와 Ag는 각각 무전해도금을 통해 지지체 표면에 증착되었으며, 합금화를 위해 도금 과정 중 H2 분위기 하에서 500°C에서 18 h 동안 열처리를 진행하였다. 제 조된 분리막의 표면과 단면은 SEM을 통해 분석되었으며, Pd-Ag 분리막의 두께는 1.88 μm, GO/γ-Al2O3 중간층을 가진 Pd-Ag 분리막의 두께는 1.07 μm로 측정되었다. EDS 분석을 통해 Pd-77%, Ag-23%의 조성으로 합금이 형성된 것을 확인하 였다. 기체투과 실험은 H2 단일가스와 H2/N2 혼합가스를 이용하여 수행되었다. H2 단일가스 투과실험에서 450°C, 4 bar 조건 하에서 Pd 분리막의 최대 H2 플럭스는 0.53 mol/m²·s로, Pd-Ag 분리막의 경우 0.76 mol/m²·s로 측정되었다. H2/N2 혼합가스 실험에서 측정된 분리막의 separation factor는 450°C, 4 bar 조건에서 Pd 분리막이 2626, Pd-Ag 분리막이 13808로 나타났다.

Skeletal muscle is an organ that regulates biological metabolic energy. Its dysfunction causes decline of body functions and disability, thus deteriorating the overall quality of life. Various materials are being developed with an anti-sarcolytic effect. However, anti-sarcolytic effect of Sinomenium acutum rhizomes extract (SAE) remains unclear. Therefore, this study aimed to investigate anti-muscle atrophy effects of SAE and its alkaloids, including sinomenine (SIN), magnoflorine (MF), acutumine (ACU), and N-ferultyramine (NFT) isolated from SAE, on dexamethasone (Dex)-induced myotubules. C2C12 myogenic cells differentiated for 6 days were treated with 1 mM Dex for 24 hours. Induction of muscular atrophy was confirmed by a decrease in myogenin expression. We found that Dex increased expression levels of muscle-specific ubiquitin ligases MuRF1 and MAFbx/atrogin-1. However, mRNA and protein levels of these muscle-specific ubiquitin ligases were significantly reduced by cotreatment with SIN, MF, and NFT in myotubes. Glucose uptake reduced by Dex in myotubules were also restored by SIN, MF, and NFT treatments. These results suggest that SIN, MF, and NFT can reduce muscle wasting and enhance glucose uptake in Dex-treated myotubes, highlighting their potential as therapeutic agents to prevent muscle atrophy.

탄소중립을 달성하기 위해 이산화탄소를 포집, 활용, 저장하는 CCUS (carbon capture, utilization, and storage) 기 술이 주목받고 있다. 본 연구에서는 광물 탄산화 공정을 통해 이산화탄소를 탄산염으로 고정하고, 이를 전이금속 탄산염 기반 리튬이온배터리 (LIB) 음극재로 적용하였다. CO2를 탄산염으로 고정후, 이를 이용해 FeCO3를 제작하고, rGO와 PVP와 복합 화하여 음극활물질에 적용하였다. rGO는 전기전도도를 높이고 입자의 응집을 방지해 부피 팽창을 완화했으며, PVP는 계면 활성제로서 입자 표면을 안정화하여 구조적 안정성을 강화하였다. FeCO3-PVP-rGO 복합체 기반한 음극재에 대한 전기화학 테스트를 진행한 결과, FeCO3/rGO 복합체는 1,620 mA/g의 전류 밀도에서 50 사이클 이후에도 400 mAh/g의 용량을 유지하 였다. 본 연구는 CO2를 고부가가치 배터리 소재로 전환하여 차세대 에너지 저장 기술에 기여할 가능성을 시사한다.

Among the products of the electrocatalytic reduction of carbon dioxide (CO2RR), CO is currently the most valuable product for industrial applications. However, poor stability is a significant obstacle to CO2RR. Therefore, we synthesized a series of bimetallic organic framework materials containing different ratios of tungsten to copper using a hydrothermal method and used them as precursors. The precursors were then subjected to pyrolysis at 800 °C under argon gas, and the M-N bimetallic sites were formed after 2 h. Loose porous structures favorable for electrocatalytic reactions were finally obtained. The material could operate at lower reduction potentials than existing catalysts and obtained higher Faraday efficiencies than comparable catalysts. Of these, the current density of WCu-C/N (W:Cu = 3:1) could be stabilized at 7.9 mA ‧ cm-2 and the FE of CO reached 94 % at a hydrogen electrode potential of -0.6 V (V vs. RHE). The novel materials made with a two-step process helped to improve the stability and selectivity of the electrocatalytic reduction of CO2 to CO, which will help to promote the commercial application of this technology.

Background: Brain-derived neurotrophic factor (BDNF) and its receptor, neurotrophic tyrosine receptor kinase-2 (NTRK2), are well known for their roles in the central nervous and animal reproductive systems. Several studies have observed the extensive expression of BDNF and NTRK2 in non-neuronal tissues, especially reproductive organs. However, most of these studies focused on ovarian development and regulation; thus, scientific research on BDNF and NTRK2 in males is required to determine their roles in the male reproductive system. Therefore, this study aimed to investigate BDNF and NTRK2 expression in bovine testes. Methods: Testes were collected from six Hanwoo bulls (6-8 months old). Reverse transcription-polymerase chain reaction (RT-PCR) analysis was performed to investigate the mRNA expression of BDNF and NTRK2 in the testes. Western blot analysis was performed to verify the cross-reactivity of BDNF and NTRK2 antibodies with bovine testicular tissues. Immunohistochemistry was conducted to determine BDNF and NTRK2 protein expression in the testes. Results: RT-PCR analysis revealed BDNF and NTRK2 mRNA expression in bovine testes. In Western blotting, BDNF and NTRK2 protein bands were observed at 32 and 45 kDa, respectively. Immunofluorescence demonstrated BDNF expression in the nuclei of spermatogonia and Sertoli cells as well as in the cytoplasm of Leydig cells. NTRK2 was exclusively expressed in Sertoli cells. These results suggest that BDNF plays a potential role in spermatogenesis via BDNF and NTRK2 signaling in bovine testes, a finding supported by previous results in different animal species. Conclusions: The expression patterns of BDNF and NTRK2 indicate their functional importance in the bovine reproductive system.

This study investigated the characteristics of personal PM2.5 exposure among 109 participants residing in Seoul over a two-month period, from February 2024 to April 2024. The participants were categorized into four sub-populations, and personal exposure to PM2.5 was assessed using portable monitors, GPS, and time-activity diaries. To understand the time-activity patterns, the daily occupancy rate for different microenvironments was calculated. Additionally, daily PM2.5 exposure contribution and integrated exposure were quantified. A time series analysis was conducted to identify differences in time-activity patterns and PM2.5 exposure among the sub-populations. ANOVA analysis indicated statistically significant differences in PM2.5 concentrations across populations and microenvironments (p<0.05). However, post-hoc analysis revealed specific microenvironments within certain sub-populations where PM2.5 concentration differences were not significant (p>0.05). All sub-populations spent more than 90% of their time indoors, and the results for exposure contribution and integrated exposure indicated that the home, which had the highest occupancy rate, was the most significant contributor to PM2.5 exposure. This study is expected to serve as foundational data for future indoor air quality management and the development of personalized strategies for reducing PM2.5 exposure.

With technological advancements, Automated Writing Evaluation (AWE) has garnered increasing interest in L2 writing research, significantly enhancing our understanding of AWE tools’ practices and efficacy in L2 writing instruction. However, the relationships between feedback types (teacher vs. AWE) and different dimensions of engagement (cognitive and affective) remain largely underexplored. This study investigates the impact of feedback types on learners’ cognitive and affective engagement, as well as their L2 writing development. Seventy-two EFL learners participated as part of their regular English curriculum. Over twelve weeks, students received feedback on their essays from either a teacher or AWE programs. Progress in writing abilities was tracked through measurement tests, and engagement questionnaires were administered. Results indicated that both feedback types improved L2 writing abilities. However, teacher feedback proved more effective in promoting students’ cognitive and affective engagement compared to AWE feedback.

Schlumbergera truncata absorbs CO2 through its mature phylloclades during the night, and can use a substantial amount of CO2 without requiring ventilation. This study investigated the growth and photosynthetic responses of S. truncata ‘Red Candle’ at two CO2 levels—ambient (≈ 400 μmol･mol-1) and elevated (≈ 1000 μmol･mol-1). At 0–8 weeks after treatment (WAT), width and length of mature phylloclade and length of immature phylloclade did not differ significantly among the CO2 treatments. At 4–8 WAT, number of branches and phylloclades were significantly greater in plants grown under ambient CO2 than those under elevated CO2. Net CO2 uptake was highest in mature phylloclades of plants grown under ambient and elevated CO2 regimes at night, at 2.51 and 1.30 μmol·CO2·m-2·s-1, respectively. However, no statistically significant variation was observed at 6 WAT, and stomatal conductance was significantly affected only by CO2 uptake time at 6 and 8 WAT. Water-use efficiency of mature and immature phylloclades at night increased with increase in CO2 levels (r = 0.7462 and 0.9312, respectively). At 123 days after treatment, plants grown under elevated CO2 had 82.7 floral buds, compared to 72.1 buds in those under ambient CO2. However, this difference was not statistically significant. Moreover, S. truncata grown under elevated CO2 exhibited decreased growth and photosynthesis, whereas the number of floral buds did not exhibit any significant differences among the treatments.

Sestrin 2 (SESN2) is a member of the sestrin family of stress-induced proteins that negatively regulate agingassociated biological processes. This study aims to investigate the role of SESN2 in regulating the differentiation potential and senescence of mesenchymal stem cells (MSCs) derived from young and elderly donors. Bulk RNA sequencing revealed a common decline in the SESN2 mRNA levels in MSCs from elderly individuals, which was confirmed via reverse transcription-polymerase chain reaction and western blot analyses. SESN2 knockdown in MSCs from young donors resulted in phenotypic changes similar to those in MSCs from elderly donors, including an enhanced expression of senescence and adipogenic markers and diminished expression of osteogenic markers. To confirm the effect of decreased SESN2 expression on osteogenic and adipogenic differentiation, we induced Sesn2 knockdown in mouse bone marrow-derived MSCs. Sesn2 knockdown suppressed the mRNA expression of osteogenic marker genes, alkaline phosphatase activity, and matrix mineralization. Furthermore, Sesn2 knockdown enhanced mRNA expression of the adipogenic marker genes and intracellular lipid accumulation. These results suggest that a decline in SESN2 expression during aging contributes to the shift of MSC differentiation from osteogenic to adipogenic lineage.

Based on the motivation theories, we postulated that interest in learning languages influences the self-efficacy beliefs of students about their capabilities as second/foreign language (L2) English learners. This study examined the longitudinal causal relation between affective interest and cognitive self-efficacy in the L2 motivational context using the Gyeonggi Education Panel Study (GEPS) data from South Korea. A secondary school student sample from 2015–2020 GEPS over six years comprised 6,314 students (3,189 males and 3,125 females). Using a parallel growth model (PPM) with Mplus 8.4, the results indicated that the initial level and growth rate of L2 English interest positively predicted L2 English self-efficacy. Subsequently, the initial level of L2 English interest exhibited a negative cross-effect on the growth rate of L2 English self-efficacy. Finally, the sequential causal effect of L2 English interest on self-efficacy was found across the six-year period. The findings are discussed in terms of the pedagogical implications in English learning and teaching practices and further research.

Metacognition in L2 listening has garnered attention, but there is limited research on concrete methods to practice it in high school EFL contexts. This study aims to investigate the effectiveness of self-annotation interventions in a high school EFL listening classroom. Through the analysis of pre- and post-listening tests, students’ annotations over 10 sessions, and a post-questionnaire, this study reveals that selfannotation interventions improve students’ comprehension, confidence, and motivation. Both higher- and lower-level students demonstrated improved L2 listening test scores compared to the control group, with the former generating more analytical selfannotations and achieving more statistically significant progress. The thematic analysis of students’ self-annotations identified recurring patterns that can inform effective listening instruction, while also enabling students to recognize and correct their mistakes, as well as receive cognitive and affective support. This study emphasizes the importance and feasibility of incorporating self-annotation in high school EFL listening classrooms, making students’ reflection processes observable and actionable, and providing recommendations for effective metacognitive interventions.

최근 딥러닝은 자기공명영상 검사에서의 화질 개선을 위해 다양하게 활용되고 있다. 하지만 다양한 자기공명영상 검사에서 딥러닝이 적용된 기법과 상황에 대한 평가는 부족한 편이다. 이에 본 연구에서는 모션 ACR(American College of Radiology) 팬텀을 활용하여 일반적인 상황과 움직이는 상황에서 T2-PROPELLER(periodically, rotated overlapping parallel lines with enhanced reconstruction, PROPELLER)와 T2-FSE(fast spin echo, FSE) 기법의 화질을 비교 평가해 보고자 하였다. 연구 결과 움직이지 않는 상황에서의 딥러닝 프로세스를 적용하였을 때 유의미한 신호대잡음비와 대조대잡음비의 상승을 보였다. 하지만 팬텀에 움직임을 주는 동적인 상황 에서 딥러닝 프로세스를 적용하였을 때 유의미한 화질 개선을 보이지 않았다. 이러한 결과는 딥러닝 프로세스를 절대 적으로 사용하기보다 다양한 상황에 맞게 선택적으로 적용하는 것이 필요할 것으로 사료된다.