검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 10,093

        1.
        2026.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Core stability exercises are widely applied in rehabilitation and training programs, but evidence regarding the effects of activation strategies and surface conditions on abdominal muscle recruitment during plank exercise remains inconsistent. Objects: This study aimed to investigate how different activation strategies (hollowing vs. bracing) and surface conditions (stable vs. unstable) influence selective activation of abdominal muscles during the plank exercise. Methods: Thirty-six healthy male adults in their 20s participated. Ultrasound imaging was used to measure the relative thickness of the transversus abdominis (TrA), internal oblique (IO), and external oblique (EO) under four randomized conditions: stable-hollowing, stable-bracing, unstable-hollowing, and unstable-bracing. Relative thickness was calculated as [(contraction – rest) ÷ rest] × 100. Data were analyzed using three-way repeated-measures ANOVA with Bonferroni comparison. Results: No significant three-way interaction was found (p = 0.840). However, a significant muscle × surface interaction indicated that TrA thickness increased more on a stable surface (p < 0.05), while IO and EO showed no difference. A significant muscle × strategy interaction revealed that hollowing induced greater relative thickness in all muscles, particularly in TrA, compared with bracing (p < 0.001). No significant strategy × surface interaction was observed (p = 0.512). Conclusion: Abdominal hollowing and a stable surface independently enhanced TrA thickness during plank exercise. These findings suggest that stable-surface plank exercise with hollowing is an effective strategy for selectively recruiting deep abdominal muscles, providing practical implications for clinical and sports settings. These findings may be specific to anklesling– induced instability and may not extend to other types of unstable surfaces.
        4,000원
        6.
        2026.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study was conducted to re-establish the withdrawal time (WT) for ivermectin (IVM) in pigs as part of the introduction of the positive list system (PLS) program. Forty-two healthy pigs were orally administered IVM at doses of 2.4 mg/kg feed (IVM-1, n = 20) and 4.8 mg/kg feed (IVM-2, n = 20) once daily for 7 days. After treatment, tissue samples were collected from four pigs at 1, 3, 5, 7, and 14 days post-administration. Based on a previously established analytical method, residual IVM concentrations in pig tissues were determined using LC-MS/MS. In the IVM-1 group, IVM levels in muscle, liver, kidney, and fat were below the limit of quantification (LOQ) on days 7, 7, 7, and 14 after the final administration, respectively. In the IVM-2 group, IVM levels in muscle, liver, kidney, and fat were below the LOQ on days 7, 14, 7, and 14 after the final administration, respectively. According to the European Medicines Agency guideline on the determination of withdrawal times, the WTs for IVM-1 and IVM-2 in edible pig tissues were established as 8 and 11 days, respectively. In conclusion, the estimated WT of IVM in swine edible tissues was shorter than the currently recommended WT of 14 days for IVM.
        4,000원
        7.
        2026.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Molecular markers have been widely utilized in population genetics, diagnostic taxonomy, and genetic mapping, and can be applied to cultivar discrimination during field selection processes for alfalfa. In this study, whole-genome sequencing information was obtained for seven alfalfa lines and cultivars developed in Korea, including ‘Alfaone (MS001)’, using Next-Generation Sequencing (NGS). Single nucleotide polymorphism (SNP) analysis revealed that ‘Alfaone (MS001)’ could be distinguished from other lines and cultivars using six SNP loci. Specifically, only two SNP loci were sufficient to differentiate ‘Alfaone (MS001)’ from major lines and cultivars such as ‘MS002’ and ‘Alfaking (MSCB07)’. This set of SNP barcodes provides a reliable standard for alfalfa cultivar discrimination, contributing to domestic cultivar protection and the advancement of the Korea forage industry. Furthermore, the development of distinguishing markers across alfalfa cultivars will enhance genetic resource identification and support the breeding of high-quality new cultivars.
        4,200원
        8.
        2026.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Mealworms (Tenebrio molitor larvae) are increasingly used as alternative protein sources in livestock feed due to their high nutritional value. Recently, interest has expanded to darkling beetle larvae capable of biodegrading polystyrene through gut-associated microbial activity. However, information regarding the safety of incorporating such styrofoam-biodegrading mealworms into poultry diets remains limited. This study evaluated the toxicological and physiological effects of replacing soybean meal with conventional mealworms (CMW) or styrofoam-biodegrading eco-mealworms (EMW) in broiler diets. Seven dietary treatments were tested in a 35-day feeding trial: a control diet without mealworms and diets containing 5%, 10%, or 15% CMW or EMW. Broilers fed diets containing 15% mealworms showed higher average daily feed intake than the control, suggesting improved feed palatability. No apparent toxicological or physiological abnormalities were observed across treatments. Organ weights, hematological indices, serum biochemical parameters, androgen levels, and tissue histopathology were within normal physiological ranges, and no significant differences were detected between CMW and EMW groups. However, as this study represents a pilot-scale evaluation with limited sample size, the statistical power to detect subtle differences may have been constrained. Thus, the absence of significant differences should not be interpreted as definitive evidence of equivalence. Within these limitations, EMW showed a safety profile comparable to CMW at dietary inclusion levels up to 15% for 35 days. Further studies with larger sample sizes are warranted to confirm these findings.
        4,000원
        9.
        2026.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 리뷰는 수국속 식물 육종 연구에서 종 활용, 교잡, 생식・생 물학적 특성, 그리고 품종 보호의 전개 양상을 종합적으로 정리 하였다. 수국속 식물 육종은 내환경성과 관상적 특성의 혼합을 위한 종내・외 교잡 과정에서는 일방적 불친화성, 자가불화합성, 수정 후 장벽과 같은 교배 친화성 문제가 실생 확보를 제한하는 주요 요인으로 작용해 왔다. 이러한 한계를 극복하기 위한 보조 기술로서 배주 배양은 종간 교잡에서 중요한 역할을 수행해 왔 다. 이러한 육종 과정의 성과는 최종적으로 품종 출원 및 등록 자료로 축적되며, 자료 분석을 통해 수국속 식물 육종의 출발점 과 변화 양상을 확인하였다. 국내 품종 출원 기록은 현재의 육종 과 시장 흐름이 관상 가치와 재배 안정성을 동시에 추구하는 방향으로 변화하고 있음을 보여주었다. 결과적으로, 본 리뷰는 교배 연구와 보조 기술, 품종보호 기록을 연계해 국내 수국속 식물 품종 개발의 연구 및 전략적 방향을 제시한다.
        5,100원
        10.
        2026.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In Korea, the agricultural industry has witnessed a growing emphasis on reducing reliance on imported forage by adopting locally available alternatives to enhance sustainability and self-sufficiency. Given the limited information on the potential use of whole-crop rice silage (WCRS) as livestock feed, this study evaluated the effects of total mixed rations (TMR) containing WCRS on the rumen microbiota of Hanwoo heifers. Thirty heifers (body weight = 351 ± 39 kg) were randomly assigned to three TMR diet groups for the early fattening period: oat hay (OH), oat hay with Italian ryegrass silage and corn silage (OIC), and silages from whole-crop rice, Italian ryegrass, and corn (WCRSEF). During the late fattening period, the same heifers (569 ± 40 kg) were reassigned to three other treatment groups: perennial ryegrass (PRG), Italian ryegrass silage and alfalfa hay (IRGA), and silage containing whole-crop rice (WCRSLF). The effects of different feeding diets on the rumen microbial composition of Hanwoo heifers were investigated using high-throughput 16S rRNA gene sequencing. The analysis revealed similar microbial diversity among the treatments across both fattening periods. Bacteroidetes and Firmicutes were the most dominant phyla during early and late fattening periods. Moreover, during the early fattening period, heifers fed WCRS exhibited a higher ratio of Bacteroidetes to Firmicutes, whereas Firmicutes became more predominant in the late fattening period. Hungateiclostridium and Porphyromonas were identified as biomarkers (LDA score > | 2 |; p < 0.05) for the WCRSEF and WCRSLF groups, respectively. Furthermore, the microbial co-occurrence network highlighted different patterns (| r | = 0.85; p < 0.05) between the early and late fattening periods. The results provide significant insights into the effects of WCRS as a substitute for conventional forages such as oat hay, perennial ryegrass, alfalfa, and Italian ryegrass silage. The findings suggest that WCRS can modulate the rumen microbiome of Hanwoo heifers.
        4,000원
        11.
        2026.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Salvia plebeia R. Brown is a medicinal plant containing various bioactive compounds, including flavonoids, and has been reported to exhibit diverse pharmacological effects such as anti-inflammatory, antioxidant, and hepatoprotective activities. However, previous studies on S. plebeia have mainly focused on phytochemical identification and pharmacological evaluation, while biotechnological approaches aimed at enhancing the productivity of major bioactive compounds—particularly metabolic regulation and content improvement through elicitor treatment in in vitro culture systems—remain largely unexplored. In this study, we investigated the effects of elicitor treatments on the accumulation of homoplantaginin, a major bioactive compound in the leaves of in vitro–cultured S. plebeia, as well as the associated changes in anti-inflammatory activity. In vitro–grown plantlets were treated with yeast extract at concentrations of 1, 2, and 5 mg/L and polyethylene glycol (PEG) at concentrations of 1, 2, and 5% (w/v), respectively. Homoplantaginin content was quantitatively analyzed using high-performance liquid chromatography (HPLC), and anti-inflammatory activity was evaluated by measuring nitric oxide (NO) production inhibition in RAW 264.7 macrophage cells. As a result, the homoplantaginin content was significantly increased in the treatment with 2 mg/L yeast extract compared to the control, while the highest NO inhibition activity was observed in the 5% PEG treatment. These findings suggest that elicitor treatment can effectively enhance the production of bioactive compounds and anti-inflammatory activity in in vitro–cultured S. plebeian. Furthermore, this study provides fundamental data supporting the potential industrial application of S. plebeia through further elucidation of metabolic pathways and optimization of culture conditions.
        4,000원
        12.
        2026.01 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        We present the result from a comprehensive laboratory and on-sky characterization of the commercial spectrograph system consisting of a PIXIS 1300BX charge-coupled device (CCD) camera and an IsoPlane 320A spectrograph as part of the preparation of the forthcoming all-sky spectroscopic survey of nearby galaxies (A-SPEC). In the laboratory, we have quantified readout noise, dark current, gain, and full-well capacity via bias, dark, and photon transfer curve analysis at all acquisition modes. To do that, we have developed a gradient correction technique to address row-dependent signal gradients in the image, which are caused by the shutter-less condition of our CCD camera test setup. The technique successfully reproduces the values in the manufacturer specifications. We also have measured quantum efficiency exceeding 80% from 400–800 nm and ≳ 90% between 450–750 nm, with sub-second persistence decay, making it ideal for rapid, multi-object spectroscopy. Using a set of diffraction gratings (150, 300, and 600 grmm−1), we have evaluated the spatial separability of multiple spectra and spectral resolution. We have conducted a test observation with this spectrograph system at the Seoul National University Astronomical Observatory (SAO) 1 m telescope and successfully demonstrated its capability of multi-object spectroscopy with moderate resolution of R ≈ 600–2600. We release all Python codes for the test and recipes to facilitate further instrument evaluations.
        5,700원
        13.
        2026.01 KCI 등재 구독 인증기관 무료, 개인회원 유료
        겨울철 온실에서의 일사량 부족은 온실 토마토(Solanum lycopersicum L.)의 수량과 품질을 제한한다. 보 광은 자연광의 한계를 보완할 수 있으나, 복합 사용에 적합한 최적 스펙트럼에 대한 경험적 근거는 여전히 부족하 다. 본 연구는 약광기 온실에서 스펙트럼이 조정된 세 종류의 LED 보광이 토마토의 광합성, 수량 및 과실 품질에 미 치는 영향을 조사하였다. 정식 60일 후, 온실에 광합성 광양자 속밀도(PPFD) 400 ± 25 μmol m-2 s-1의 발광다이오 드(LED)를 조사하였으며(full-스펙트럼 LED 및 특정 full-스펙트럼 LED[청색 및 녹색 파장]), 청색 영역의 파장 피 크를 엽록소 a 흡수에 맞춘 백색 스펙트럼을 사용하였고, 대조구는 보광 없이 재배하였다. 보광 처리시 대조군 대비 평균 수량이 26% 증가하였으며, 파장 변환 전스펙트럼 백색광에서는 총 과실 수량이 58% 증가하였다. 또한 보광 은 순광합성속도를 향상시켰고, 과실 당도를 5% 이상 증가시켰다. 리코펜 함량과 ABTS 라디칼 소거 활성은 대조 군에서 높았으며, pH와 적정산도는 대조되는 경향을 보였다. 전반적으로, 본 연구 결과는 보광의 파장 피크를 광합 성 색소 흡수 파장에 맞추는 것이 토마토 수량을 향상시킴을 시사한다. 그러나 수량의 증가는 주요 파이토케미컬 성 분의 감소를 수반하며, 이는 온실 생산 시스템 최적화에서 중요한 상충 관계를 강조한다.
        4,000원
        14.
        2025.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Real-time ergonomic risk assessment in manufacturing environments is challenged by severe class imbalance in high-risk postures and the need for deployment-efficient models. Conventional oversampling techniques may violate biomechanical constraints, limiting their suitability for human motion data. Objectives: This study aimed to compare multiple machine learning models for real-time ergonomic risk assessment while addressing data imbalance using biomechanically appropriate learning strategies and evaluating both predictive performance and deployment efficiency. Design: Comparative study. Methods: A large-scale workplace safety dataset comprising image-based skeletal keypoints was analyzed. To mitigate class imbalance without generating biomechanically implausible samples, cost-sensitive learning and focal loss were employed instead of synthetic oversampling. Subject-wise data splitting was applied to prevent data leakage. Five model families, including Random Forest, convolutional neural networks, and a lightweight graphbased network, were evaluated using accuracy, F1-score, area under the receiver operating characteristic curve (AUC), and high-risk recall. Statistical significance was assessed using bootstrap confidence intervals and McNemar and DeLong tests. Results: The lightweight graph-based model demonstrated competitive classification performance while maintaining reduced computational complexity. Although none of the models achieved the predefined high-risk recall threshold, statistically significant performance differences were observed across model families. Conclusion: The findings suggest that biomechanically informed imbalance handling improves methodological validity in ergonomic risk assessment. While deployment feasibility appears promising, further empirical validation on edge hardware is required.
        4,300원
        15.
        2025.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Plank exercises are widely used for core stabilization, but the effects of applying instability to different support surfaces on trunk muscle activation remain unclear. Objectives: This study aimed to investigate the effect of support surface instability on the electromyographic activity of trunk muscles including the rectus abdominis, internal oblique and transversus abdominis, multifidus, and longissimus during the plank exercise. Design: This study is quasi-experimental design. Methods: Thirty healthy university students performed plank exercises under four conditions: stable surface, unstable elbows, unstable feet, and unstable both. Muscle activity was measured using wireless EMG. Data were analyzed using one-way repeated measures ANOVA and Scheffé post hoc tests. Results: The rectus abdominis showed a statistically significant increase in muscle activation when both elbows and feet were placed on an unstable surface compared with the stable condition (P<.05). Conclusions: Unstable support surfaces during planks significantly enhance rectus abdominis activation, increasing global muscle recruitment for postural control. Conversely, stable surfaces may be preferable for training deep stabilizers without excessive superficial muscle dominance.
        4,000원
        16.
        2025.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Falls are a leading cause of injury among older adults, with rural elderly populations in Gyeongsangnam-do, South Korea, experiencing particularly high fall rates (8.4%). Shoulder dysfunction is prevalent among rural older adults and may contribute to impaired balance and increased fall risk. Community-based interventions targeting shoulder function represent a potential strategy for fall prevention in underserved rural areas. Objectives: This study investigated the impact of targeted shoulder-focused physical therapy on enhancing upper-limb function and postural stability among community-dwelling older adults in rural regions. Design: A pre-post intervention study. Methods: Forty-four older adults aged 65 years and above from five rural communities in Gyeongsangnam-do, South Korea, participated in this study. Assessments were performed before and after two intervention sessions spaced two weeks apart. Shoulder function was assessed using the Apley's scratch test and TheraBand resistance for abduction and flexion strength. Balance was measured using the BT-4 Balance Trainer for static and dynamic stability, and functional mobility was examined through sit-to-stand and timed up-and-go tests. The intervention included 20 minutes of individualized physical therapy by an experienced therapist and 20 minutes of personalized exercise guidance by trained student researchers. Results: Shoulder range of motion and muscle strength in both abduction and flexion showed significant improvement (P<.05). Static balance (C90 area with eyes closed) and dynamic balance in forward and lateral directions demonstrated significant enhancement (P<.05). No significant changes were observed in functional mobility tests. Conclusion: Shoulder-specific physical therapy programs can effectively improve upper-limb function and balance control, thereby reducing fall risk among rural older adults as a practical community-based fall prevention strategy.
        4,000원
        17.
        2025.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The high theoretical capacity of transition metal-based compounds makes them promising candidates for lithium-ion battery (LIB) anodes. Among them, iron selenide (FeSe2) has attracted considerable interest because of its excellent electrical conductivity and superior lithium storage capacity. However, pristine FeSe2 suffers from rapid capacity fading and structural instability during repeated cycling. Thus, this study used a facile solvothermal method to synthesize a FeSe2@rGO composite with enhanced structural integrity and electrical conductivity. By incorporating reduced graphene oxide (rGO), the composite demonstrated improved charge transfer kinetics and mechanical robustness. Morphological and structural characterizations were performed using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy analyses (XPS), which confirmed the successful formation of the composite and its uniform distribution. Electrochemical properties were evaluated using cyclic voltammetry (CV), galvanostatic charge-discharge, long-term cycling, and electrochemical impedance spectroscopy. The optimized FeSe2@rGO electrode delivered a high reversible capacity of 971.95 mAhg-1 at 500 mAg-1 after 350 cycles. The underlying charge storage mechanism was investigated using scan rate-dependent CV, which revealed a dominant capacitivecontrolled contribution at higher scan rates. The study findings indicate that the FeSe2@rGO composite can serve as a high-performance anode material with excellent cycling stability and rate capability, providing a viable strategy for the development of advanced LIBs.
        4,000원
        18.
        2025.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study investigates the repeated impact behavior and compression-after-impact (CAI) performance of triaxially braided carbon/glass fiber-reinforced polymer (C/GFRP) composite tubes. A two-stage experimental strategy was proposed to evaluate the synergistic effect of interlayer hybridization and axial yarn reinforcement on damage evolution and mechanical performance. In Stage I, six hybrid braided tubes with different carbon/glass stacking configurations—including pure carbon, pure glass, layered, and reversed-layered structures—were subjected to repeated low-velocity impacts at 31 J. Micro-CT was employed to reconstruct the internal damage morphology and assess damage accumulation. The optimal interlayer configuration was selected based on impact force, displacement, energy absorption, and internal failure characteristics. In Stage II, the selected structure was further reinforced with four types of axial yarns (none, carbon, glass, and carbon/glass alternating), and their axial compressive and CAI performance after 10 J impact was tested. Results revealed that reversed interlayer design effectively suppressed crack propagation and improved damage tolerance under cyclic impacts. Moreover, the inclusion of hybrid axial yarns significantly enhanced residual compressive strength without compromising energy absorption. This study establishes a lightweight, high-performance braided tube design strategy suitable for aerospace and transportation applications.
        5,700원
        19.
        2025.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, GNPs/FeCoNiCuAl particles synergistically reinforced aluminum matrix composites are developed by friction stir processing (FSP) to explore the effects of different GNPs contents (1, 3, and 5%) on the microstructure, mechanical performance, and wear resistance of the materials. The results show that the incorporation of GNPs affects the formation of the diffusion layer between the FeCoNiCuAl particles and the aluminum matrix. As the content of GNPs increases, the thickness and integrity of the diffusion layer between FeCoNiCuAl particles and aluminum matrix gradually decrease. In addition, the introduction of GNPs is beneficial in enhancing the proportion of high-angle grain boundaries in the composites, but the grain size of the specimen increases slightly to about 5.5 μm at a content of 5% GNPs. When the content of GNPs is 1%, the composites achieve the highest microhardness and the lowest specific wear rate (0.1459 × 10⁻⁶ mm3/ N·m), with the wear mechanism dominated by abrasive wear. Nonetheless, when the GNPs content in the composite increases to 5%, the thickness and integrity of the diffusion layer are minimal, causing the tensile strength of the composite to be reduced to 250 MPa, and the specific wear rate increased to 0.4244 × 10– 6 ( mm3/N·m), with the wear mechanism transformed to abrasive–adhesive mixed wear. This study demonstrates that the appropriate ratio of GNPs and FeCoNiCuAl particles can effectively enhance the mechanical and wear resistance properties of aluminum matrix composites, providing a theoretical basis for the design and development of high-performance aluminum matrix composites.
        5,100원
        20.
        2025.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Poor bonding occurs with resin due to surface inertness of carbon fiber (CF), so CF surfaces were often treated. In some common surface treatments, sizing was a simple and effective modification method. Polyurethane (PU) was used as the main component of sizing agents due to its similar structure to polyamide 6 (PA6). The CF/PA6 composites’ interfacial properties were improved using PU as a sizing agent. Meanwhile, in this paper, glycidol (GLD) was introduced into the PU emulsion so that the epoxy group reacted with the carboxyl group on the acidified CF. After testing, when the content of glycidyl in the sizing agent is 2%, the CF/PA6 composites showed an important improvement in tensile, impact, and flexural strengths, which increased by 49.4%, 94.6%, and 53.2%, respectively. In addition, the effect of modified WPU sizing agents with different GLD contents on the properties of CF/PA6 composites was investigated.
        4,000원
        1 2 3 4 5