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        검색결과 9,532

        141.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: The Nordic hamstring exercise is effective as a representative exercise for strengthening eccentric contraction that can activate the hamstring at high levels, improve eccentric contraction strength and ability, and significantly reduce injury rates. Objectives: To investigated a comparison with the lunge exercise to determine the effect of the Nordic hamstring exercise on muscle activity and balance ability in a sample of adult amateurs and football players. Design: Randomized controlled trials. Methods: The subjects of the study were stratified samples of 28 professional and amateur football players and two groups (Nordic hamstring group and lunge group) of 14 people each were studied. Surface electromyography using, was performed to measure the hamstring muscle activity, and the good morning exercise was selected as the measurement exercise. For balance ability, the surface area ellipse and length were measured with BioRescue, while for static balance, the posture of closing the eyes and single-limb standing was measured, and for dynamic balance the one-legged squat was measured. Results: The %MVIC of the semitendinosus and the biceps femoris improved in the Nordic hamstring exercise group and showed statistically significant increase (P<.05). The static and dynamic balance improved in the Nordic hamstring exercise group and showed statistically significant decrease (P<.05). Conclusion: The Nordic hamstring exercise can be useful as an exercise to improve the hamstring muscle activity and balance ability of professional and amateur football players.
        4,200원
        142.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        해사영어는 선박 운항, 해양 안전, 선내 의사소통 및 선외 교신을 위해 설계된 특수한 영어 언어체계이다. 국제해사기구 STCW(선원의 훈련, 자격증명 및 당직근무의 기준에 관한 국제협약)에 따르면 국제항해에 종사하는 항해사가 되기 위해서는 SMCP를 포함한 해사영어 대한 충분한 이해가 수반되어야 한다. 본 연구는 음성인식, 번역, 단어 기입 등 유형의 해사영어시험을 통하여 학생들 의 해사영어 활용 능력을 측정하고 플랫폼 사용에 따른 시험 점수 향상 정도, 나아가 초임항해사로 나가기 위하여 요구되는 해사영어 시험 플랫폼 활용 시간 등을 조사하고자 하였다. 실험은 먼저 초기 시험을 통해 학생들의 일반영어능력과 SMCP 활용 능력에 대한 연 관성을 조사한 후, 중간 시험 및 최종 시험을 통해 플랫폼 활용에 대한 점수 향상 정도, 응시시간 변화 등 요인을 측정하였다. 초기 시 험을 통해 개인 요인(예: 토익 점수, 본인 스스로에 대한 영어능력 평가)에 따른 그룹 간 해사영어시험 점수에 유의한 차이가 있음을 확인하였으며, 중간시험 및 최종시험을 통해 플랫폼 활용이 유의한 시험점수 향상으로 이어졌음을 확인하였다. 해당 연구는 해사 교육 분야에 다양하게 적용할 수 있는 학습 플랫폼 활용 효능을 조사하였으며 향후 해사영어 교육 외 그 범위를 넓혀 활용될 수 있을 것으 로 사료된다.
        4,000원
        143.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study is to analyze the formative characteristics of women’s costumes among the Regency era’s elite in the television drama Bridgerton (2020). Its methodology investigates the socio-cultural background and literature on clothing in the Regency era. It also analyzes the formative elements of Daphne’s costumes (of the Bridgerton family) and Penelope’s costumes (of the Featherington family) representing the upper class. The study reveals that women’s costumes had a tubular silhouette consisting of a low neckline, high waistline, and short puffed sleeves. The series expressed well the Regency-era costumes, which were influenced by Neoclassicism and characterized by silk materials, shawls, gloves, belts, a reticule, and hairstyles. Among the formative elements, the Bridgerton and Featherington families’ costumes showed distinct differences in color, materials, patterns, accessories, and hairstyles. Daphne’s costumes were intelligent and elegant in pastel-toned blues and had small patterns. She carried small accessories and had a natural curled hairstyle. In contrast, Penelope wore decorative and splendid styles in intense colors and large patterns. Her accessories were large and colorful, and she had a strong curled hairstyle. These costumes express the Bridgerton family as aristocratic and the Petringer family as flashy, thereby distinguishing the two families. These research results will be presented as basic data for producing drama costumes in the 19th century to help complete the drama.
        4,500원
        144.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Along with other heavy metals, arsenic (As) is one among the substances most harmful to living organisms including humans. Owing to its morphological similarity to phosphorus, the uptake of As is influenced by photosynthesis and the phosphorus uptake pathway. In this study, we varied arsenic exposure and light intensity during nutrient solution cultivation of lettuce (Lactuca sativa L.) to determine the effect of these two factors on arsenic uptake, lettuce growth, and electron transfer in photosystem II. In the treatment exposed to 30 μmol L-1 of arsenic, the shoot arsenic concentration increased from 4.73 mg kg-1 to 18.97 mg kg-1 as the light intensity increased from 22 to 122 μmol m-2 s-1. The water content and ET2o/RC of the shoots were not affected by arsenic at low light intensity; however, at optimal light intensity, they decreased progressively with arsenic exposure. Increased light intensity stimulated the growth of plant roots and shoots; contrarily, the difference in growth decreased as the concentration of As exposure increased. The results of this study suggest that the effect of As on plant growth is dependent on light intensity; in particular, an increase in light intensity can increase the uptake of As, thereby affecting plant growth and As toxicity.
        4,000원
        145.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Hypertension is characterized by excessive renin-angiotensin system activity, leading to blood vessel constriction. Several synthetic compounds have been developed to inhibit renin and angiotensin-converting enzyme (ACE). These drugs often have adverse side effects, driving the exploration of plant protein-derived peptides as alternative or supplementary treatments. This study assessed the phenolic compound and amino acid content and the antioxidant and antihypertensive activity of 5 South Korean staple crops. Sorghum had the highest phenolic compound content and exhibited the highest antioxidant activity. Millet grains, particularly finger millet (38.86%), showed higher antihypertensive activity than red beans (14.42%) and sorghum (17.16%). Finger millet was found to contain a large proportion of branched-chain, aromatic, and sulfur-containing amino acids, which are associated with ACE inhibition. In particular, cysteine content was positively correlated with ACE inhibition in the crops tested (r=0.696, p<0.01). This study confirmed that the amino acid composition was more correlated with the antihypertensive activity of grains than the phenolic compound content. Finger millet mainly contained amino acids, which have higher ACE inhibitory activity, resulting in the strongest antihypertensive activity. These findings underscore the antihypertensive potential of select crops as plant-based food ingredients, offering insight into their biological functions.
        4,200원
        146.
        2023.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        This comprehensive study delves into the intricate process of exfoliating and functionalizing boron nitride nanosheets (BNNSs) extracted from hexagonal boron nitride (h-BN), and meticulously explores their potential application within epoxy composites. The extensive research methodology encompasses a sequence of treatments involving hydrothermal and sonication processes aimed at augmenting the dispersion of BNNSs in solvents. Leveraging advanced analytical techniques such as Raman spectroscopy, X-ray diffraction, and FTIR spectroscopy, the study rigorously analyzes a spectrum of changes in the BNNS’s properties, including layer count variations, interlayer interactions, crystal structure modifications, and the introduction of functional groups. The research also rigorously evaluates the impact of integrating BNNSs, specifically glycidyl methacrylate (GMA)-functionalized BNNSs, on the thermal conductivity of epoxy composites. The conclusive findings exhibit notable enhancements in thermal properties, predominantly attributed to the enhanced dispersion of fillers and enhanced interactions within the epoxy matrix. This pioneering work illuminates the wide potential of functionalized BNNSs for significantly enhancing the thermal conductivity of epoxy composites, paving the way for advanced materials engineering and practical applications.
        4,000원
        147.
        2023.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        A transfer cask serves as the container for transporting and handling canisters loaded with spent nuclear fuels from light water reactors. This study focuses on a cylindrical transfer cask, standing at 5,300 mm with an external diameter of 2,170 mm, featuring impact limiters on the top and bottom sides. The base of the cask body has an openable/closable lid for loading canisters with storage modules. The transfer cask houses a canister containing spent nuclear fuels from lightweight reactors, serving as the confinement boundary while the cask itself lacks the confinement structure. The objective of this study was to conduct a structural analysis evaluation of the transfer cask, currently under development in Korea, ensuring its safety. This evaluation encompasses analyses of loads under normal, off-normal, and accident conditions, adhering to NUREG-2215. Structural integrity was assessed by comparing combined results for each load against stress limits. The results confirm that the transfer cask meets stress limits across normal, off-normal, and accident conditions, establishing its structural safety.
        4,600원
        148.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The present study describes Philodromus paiki sp. nov., which was previously misidentified as P. fuscomarginatus (De Geer, 1778), P. poecilus (Thorell, 1872), and P. spinitarsis Simon, 1895 in Korea, as a new species with diagnosis, detailed descriptions, and taxonomic photographs. Additionally, P. spinitarsis is also described to correct previous misidentifications of Korean records of the species.
        4,000원
        149.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Abstract Purpose : To investigate the prevalence and risk factors for dry eye syndrome (DES) in university students. Methods : A cross-sectional survey of university students was conducted through a combination of online smartphone surveys using Google Forms and face-to-face questionnaires. The questionnaire consisted of questions about risk factors for dry eye disease and the 5-item Dry Eye Questionnaire (DEQ-5). Results : A total of 288 university students participated in the study. The average age was 22.5±2.1 years, w ith 54.2% female a nd 4 5.8% m ale. The m ean of t he D EQ-5 s core w as 7.37±4.65, and the prevalence of DES by DEQ-5 was 47.2%. Female gender (p=0.012), digital screen use for more than 8 hours per day (p=0.018), digital screen use for more than two hours without a break (p=0.035), contact lens wear (p=0.016), refractive surgery (p=0.020), less than 6 hours of sleep per night (p=0.0169, and allergic conjunctivitis (p=0.016) were relevant associated risk factors for DES. Conclusion : The prevalence of DES in young adults may be underestimated in comparison to middle-aged and older adults. The severity of DES depends on several factors, including genetic and environmental factors, so identifying risk factors would help with proper prevention and early diagnosis. Key words : DEQ-5, Dry eye syndrome, Risk factor
        4,000원
        150.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Abstract Purpose : To investigate the effect of the amount of astigmatism on distance and near vertical heterophoria in adults aged 20~40 years. Methods : Thirty subjects (31.25±10.21 years) were participated, and refraction was performed using I-Profilerplus and a phoropter, and horizontal heterophoria (HH) and vertical heterophoria (VH) teats were conducted at distance and near using a Torrington chart. Results : HH and VH were approximately 0.80 △ (p=0.001) and 0.20 △ (p=0.002) greater at near than at distance, respectively. Spherical refractive errors did not correlate with HH and VH at distance and near. There was no correlation between astigmatism and HH at either distance or near (p=0.141, p=0.318, respectively), but VH at distance and near was significantly correlated with astigmatism (both, p < 0.001), the amount of VH increased with increasing the amount of astigmatism. Conclusion : We found that the amount of astigmatism affected the VH at both distance and near and that the amount of VH increased with increasing astigmatism. These findings suggest that it is important to assess both astigmatism and VH in clinical practice, and that correction of astigmatism may help to reduce symptoms of VH. Key words : Astigmatism, Horizontal heterophoria, Refractive error, Vertical heterophoria
        4,000원
        151.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Abstract Purpose : The distribution of axial length and ocular dimensions was investigated, and each correlation according to gender and age was investigated. Methods : Among 847 eyes of 438 patients, 207 eyes in 20s, 210 eyes in 30s, 216 eyes in 40s, and 214 eyes in 50s were measured for axial length with IOL-Master 700. Refractive error was measured with KR-800. Corneal curvature radius and corneal eccentricity were measured with Keratograph 4. Results : Axial length (male: 24.57±1.22mm, female: 24.03±1.12mm) and horizontal corneal eccentricity (male: 0.58±0.11, female: 0.54±0.12) tended to increase in decreased age, male and myopia. Mean corneal curvature radius (male: 7.82±0.25mm, female: 7.71±0.25 mm), and horizontal corneal curvature radius (male: 7.91±0.26 mm, female: 7.79±0.26mm), nasal corneal eccentricity (male: 0.68±0.14, female: 0.66±0.15), and temporal corneal eccentricity (male: 0.45±0.14, female: 0.44±0.13) tended to increase in decreased age and male. Mean corneal eccentricity (male: 0.57±0.12, female: 0.54±0.12), vertical corneal curvature radius (male: 7.71±0.27 mm, female: 7.65±0.24 mm), vertical corneal eccentricity (male: 0.56±0.15, female: 0.54±0.15), and inferior corneal eccentricity (male: 0.52±0.19, female: 0.46±0.22) tended to increase in male. The correlation with axial length and corneal curvature radius showed a high correlation in emmetropia and the horizontal. Horizontal and temporal corneal eccentricity showed a low correlation. Conclusion : Axial length, corneal curvature radius, and corneal eccentricity (excluding vertical) were higher in males. As age increased, axial length, and corneal curvature radius decreased. Among the 4 quadrants of corneal eccentricity, only the temporal s ide showed a significant correlation with axial length. Key words : Age, Axial length, Corneal curvature radius, Corneal eccentricity, Gender Authors ORCID:†
        5,500원
        152.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Abstract Purpose : The aim of this study was to identify knowledge and lifestyle habits for glaucoma prevention and to present basic data for future glaucoma prevention education. Methods : From April to September 2023, 447 people in their 20s to 60s were selected and an online survey was conducted. The questionnaire consisted of a total of 30 questions, including 6 questions about the subject's general characteristics, 14 questions about knowledge and awareness of glaucoma, and 10 questions about lifestyle habits related to intraocular pressure. Results : 89.7% responded that they had heard of glaucoma, and 31.1% of respondents knew the difference between glaucoma and cataracts. 34.5% responded that early detection is difficult, 33.3% that complete treatment is difficult, 23.5% that even normal intraocular pressure can cause glaucoma, and 36.0% that the incidence of glaucoma is increasing day by day. The level of awareness and knowledge was higher with age, in women than men, in those with a family history, in professional occupations, with metabolic diseases, and with high myopia. Lifestyle habits related to intraocular pressure were higher with age, among women, when smartphone use was less than 3 hours, and among housewives and professionals. The relationship between glaucoma knowledge and awareness and intraocular pressure-related lifestyle habits was statistically significant (r=0.248, p<0.001). Conclusion : Although the level of basic knowledge about glaucoma was high, the level of specific knowledge was low compared to the increase in the incidence of glaucoma over the past 10 years. Key words : Glaucoma, Healthy Life Practices, Intraocular pressure
        4,500원
        153.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        굴파리과에 기생하는 종으로 알려진 Bitomus (갗고치벌속)는 한국에 4종 보고되어있다. Bitomus는 Fischer (1987, 1994)에 의해 개정되었 고, Papp (1978, 1981)에 의해 한국에서 보고되었다. Bitomus는 움직이지 않게 연결된 마치 껍질과 같은 2-3번째 또는 4번째 복부마디로 다른 속들 과 구별된다. 본 조사연구 결과로 Bitomus indicus를 국내 최초로 보고한다. 기술과 진단형질도판을 수록한다.
        4,000원
        154.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Abstract Purpose : To determine the perceptions of soft contact lens wearers regarding contact lens wear and care, and their knowledge of adverse effects of contact lens wear by self-assessment. Methods : An online survey using smartphone was conducted by Naver and Google questionnaires among university students who have experience wearing soft contact lenses. Results : Two hundred twenty-eight soft lens wearers were participated in the study. The average age was 20.9±1.7 years (female 72.8%; male 27.2%) were university students. Approximately 25.4% of respondents did not receive training and practices for safe soft lens wear and 14.1% evaluated themselves as poor at wearing and caring for soft lenses. The most uncomfortable symptom of soft lens wear was dryness at 76.3%, and 36.0% experienced soft lens-related adverse events. The higher type of adverse event was conjunctivitis, and the most common self-reported cause of contact lens-related adverse events was improper lens care and non-compliance to lens wear regimens. Conclusion : Based on the self-assessment of soft lens care that resulted from this survey, we believe that a more proactive approach to intervention by contact lens practitioners is still needed to prevent the risk of adverse events and improve soft lens wearer behavior. Key words : Compliance, Contact lens-related adverse events, Self-assessment, Soft contact lens Authors ORCID:†
        4,500원
        155.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 한국산 미기록속인 이마줄불청객파리속(신칭)과 미기록종인 작은눈이마줄불청객파리(신칭)를 처음으로 보고한다. 우리는 이 종이 포식성 거미의 섭식과정에 관여하는 phoretic relationship의 습성을 갖는 것을 확인하였다. 이 종의 성충에 대한 기재문과 사진 및 DNA바 코드 서열을 제공한다.
        4,000원
        156.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Abstract Purpose : This study investigated the impact of knowledge and awareness of perception of harmful rays on the use of blue light blocking lenses among university students majoring in optometry. Methods : This study targeted 65 optometry students who responded to an online survey from September 2023 to October 2023. The survey used a survey tool with a total of 15 questions, including knowledge and awareness of perception of harmful rays and demands for guidelines. Statistical analysis was performed using SPSS 19.0. Results : The overall knowledge score about UV rays and blue light was 14.00±3.10 for optometry students and 12.30±3.50 for general university students, showing that the optometry students had higher knowledge (p<0.001). In the case of use of UV-blocking lenses, 70.8% of optometry students were found to be using them, which was higher than 51.5% of general university students. The use of glasses to block blue light was found to be 41.5% of optometry students and 36.9% of general university students. The correlation between perception of the importance of blocking harmful rays and the need for guidelines for the correct selection of blue light blocking lenses was r=0.528 (p<0.001). Conclusion : Optometry students' knowledge and perception of harmful rays were found to be higher than those of general university students, and it appears to have an impact on the use of harmful ray-blocking lenses. Therefore, it is necessary to strengthen education and establish guidelines for the correct selection of harmful ray blocking lenses.
        4,000원
        157.
        2023.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        This study investigated the effects of exposure frequency, depth of processing, and activity repetition types on vocabulary learning. In total, 78 South Korean fifth-grade students were divided into four conditions. Students in each condition were asked to read a passage with four of the eight target words (exposure: four times) and the other four words (exposure: once) for three days, and to perform the vocabulary activities assigned to each condition. According to the results, exposure frequency and activity repetition type had significant effects on vocabulary learning. Activity repetition type also had a significant interaction effect with exposure frequency and depth of processing. Notably, presenting a word 12 times (4x3) in reading intervals had a more positive impact on vocabulary learning than presenting it three times (1x3), particularly when different vocabulary activities were repeated. Meanwhile, when the same activity was repeated, an activity with a higher depth of processing was more effective for vocabulary learning.
        7,000원
        158.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        제충국(Tanacetum cineariaiaefolium), 데리스(Derris elliptica), 고삼(Sophora flavescens) 추출물은 다양한 해충을 방제하는데 사용되고 있다. 하지만, 국내에서 판매되고 있는 식물추춞물 자재는 유효성분의 표기가 없고, 살충농도와 살충시간에 대한 자료가 전무한 상황이다. 본 연구에서는 상 용화된 주요 식물추출물의 살충유효성분의 농도를 결정하고 복숭아혹진딧물에 대해 살충농도와 살충시간을 측정하였다. 식물추출물의 살충활성성분 인 pyrethrins, rotenone, matrine과 oxymatrine의 농도는 액체 크로마토그래피에서 표준물질을 활용하여 질량분석을 통해 측정하였다. 식물추출 물을 농도별로 희석하여 복숭아혹진딧물에 살포하여 살충력을 측정하였다. 표준화합물과 비교한 후 질량분석 및 결정했습니다. Myzus persicae에 대 한 lethal concentation과 lethal time을 조사했다. 살포 후 48시간 후 치사 농도(LC50)는 pyrethrins (20.4 ppm), roteone (34.1 ppm), matrine (29.6 ppm)였고, 100 ppm 살포한 LT50은 pyrethrins (13.4시간), rotenone (15.1시간), matrine (14.4시간)로 측정되었다. Kaplan-Meier 생존분 석 결과, 100 ppm에서 세 가지 식물 추출물의 LT50은 대조구인 화학 살충제인 Sulfoxaflor를 살포 처리구보다 유의하게 빨랐습니다. 본 결과는 복숭 아혹진딧물 방제를 위해 식물추출물의 제형화에 단일 또는 혼합 제제를 개발하는데 기준 살충농도와 살충시간을 제고하는데 의미가 있다.
        4,000원
        159.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Estrus in cows can be detected through vaginal electrical resistance or conductivity. However, there are no studies measuring vaginal electrical resistance in Hanwoo cows. This study aims to measure the vaginal electrical resistance value in Hanwoo cows and compare it with estrus and ovulation. Methods: Vaginal electrical resistance values of 73 Hanwoo cows were measured before and after estrus at the Gyeongsangbuk-do Livestock Research Institute. Measurements were taken on days -6, -3, -2, -1, 0, 1, 2, 3, and 6 of artificial insemination. Large follicles and ovulation were confirmed using transvaginal ultrasonography. Results: The vaginal electrical resistance averaged 225.6 ± 6.3 Ω days before the artificial insemination date, decreasing until the day of artificial insemination. The average vaginal electrical resistance was 163.7 ± 4.6 Ω on the date of artificial insemination, and 188.8 ± 4.3 Ω one day after artificial insemination, when large follicles were observed. In addition, on the 6th day after artificial insemination, the vaginal electrical resistance averaged 231.4 ± 5.5, which was similar to the 6th day before artificial insemination (222.5 ± 6.3). Transvaginal ultrasonography showed that most of the cows ovulated one day after artificial insemination. Conclusions: The accuracy of estrus is high if the vaginal electrical resistance is measured for cows with confirmed estrus, making is a potentially useful for determining the timing of artificial insemination.
        4,000원
        160.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Forward head posture (FHP) is a musculoskeletal disorder that causes neck pain. Several exercise interventions have been used in South Korea to improve craniovertebral angle (CVA) and relieve neck pain. There has been no domestic literature review study over the past 5 years that has investigated trends and effects of exercise intervention methods for CVA with neck pain. This domestic literature review aimed to evaluate the trends and effects of exercise interventions on CVA and neck pain in persons with FHP. A review of domestic literature published in Korean or English language between 2018 and 2022 was performed. Literature search was conducted on Google Scholar and Korea Citation Index by using the following keywords: “exercise,” “exercise therapy,” “exercise program,” “forward head posture,” and “neck pain.” Ten studies were included in this review. All of the studies showed positive improvements after intervention programs that included exercises. Notably, four of these studies demonstrated significant differences in results between the experimental and control groups. Among the 10 studies, nine measured visual analogue scale or numerical rating scale scores and reported significant reductions in pain following interventions, including exercise programs. Five of these studies showed significant differences in results between the experimental and control groups. Furthermore, six studies that used neck disability index exhibited a significant decrease in symptoms after implementing intervention programs that included exercise, and significant differences in results were found between the experimental and control groups. This domestic literature review provides consistent evidence to support the application of various exercise intervention programs to improve CVA and relieve neck pain from FHP. Further studies are warranted to review the effects of various exercise interventions on FHP reported not only in domestic but also in international literature.
        4,000원