Earticle

본 연구의 목적은 감정 발화 음성 녹음을 통해 대상 아동의 나이(전학령기-학령기)에 따른 음도, 강도, 발화 속도에 차이가 존재하는지 분석하기 위해서이다. 또한, 감정과 음도-강도-발화 속도 간 연관성을 확인하고자 한다. 만 4-9세의 정상 발달기 아동 35명이 본 연구에 참여하였다. 한국형 감정 발화 데이터베이스(KAV DB)에 속한 문장 발화를 통한 세 가지 감정(기쁨, 슬픔, 분노)의 음도-강도-발화 속도가 측정되었다. 최대/최소 음도, 최대/최소 강도, 발화속도가 이원혼합분석을 이용해 측정되었다. 전학령기-학령기 학령기 아동 사이에 유의한 음도 차이가 관찰되었다. 분노의 음도가 가장 높았으며 기쁨-슬픔이 뒤를 이었다. 평균 강도 측정 결과, 학령기 아동들이 감정 발화 시 더욱 높은 강도로 발화했다. 감정 별 강도 측정 시, 기쁨의 강도가 슬픔보다 높았으며, 분노의 강도가 슬픔보다 높았다. 발화 속도에 있어서 집단 간 높은 유의도가 확인되었다. 발화 속도 측정 시, 기쁨의 발화 속도가 슬픔과 비교해 빨랐으며, 분노의 발화 속도가 기쁨-슬픔과 비교해 빨랐다. 기쁨-슬픔의 이차 상호 작용 효과에서 유의도가 높았다. 상호 작용 효과를 기반으로 발화 속도에서 집단 간 차이를 확인할 수 있었다. 본 연구는 음도-강도-발화 속도 간 감정 별 차이가 존재함을 시사한다. 또한, 결론을 통해 연령 별 감정 발화의 차이를 확인할 수 있다.

This study aimed to investigate the acoustic characteristics of emotional speech in typically developing children. Thirteen preschoolers (4-5.9 years old) and 22 school-aged children (6-9.9 years old) participated in the study. The children were asked to imitate 15 utterances based on emotional utterances representing three different emotional expressions (happy, sad, and angry). Basic measures of the frequency, intensity, and duration of emotional expressions in the children's utterances were obtained as averages. We found that both preschoolers and school-aged children differentially imitated the emotional utterances in terms of basic frequency, intensity, and duration depending on the type of emotion (happy, sad, angry). In particular, we found that school-aged children spoke more slowly than preschoolers when expressing sadness. These results suggest that preschoolers and school-aged children can express emotions by modulating vocal pitch, intensity, and duration. In addition, school-aged children tended to modulate the duration parameter of prosodic elements to express different emotions compared to preschoolers. In general, differences in duration between developing children may be influenced by the maturity of the child's speech and language development.

Various vaccines were rapidly developed during the COVID-19 pandemic to prevent and treat infections but global infections continue, and concerns about new mutations and infectious diseases persist. Thus, active research focuses on developing, producing, and supplying vaccines and treatments for various infectious diseases and potential pandemics. Natural killer(NK) cells, as innate immune cells, can recognize and eliminate abnormal cells like virus-infected and cancer cells. Hence, their development as anticancer and antiviral treatments is rapidly advancing. In this study, optimal short-term culture conditions were identified for allogeneic NK cells by simplifying the culture process through the isolation of NK cells(referred to as NKi cells) and eliminating CD3+ cells(referred to as CD3- cells). NK cells demonstrated reduced viral titer in injection of NK cells into SARS-CoV-2 infected ACE-tg mice increased survival. The study's findings could form the basis for an antiviral treatment platform that swiftly responds to new viral disease pandemics.

활성산소종은 미토콘드리아 대사활동을 통해 생성되는 반응성이 강한 산소 함유 분자로서 특히 간에서 복잡한 세포 분자와 반응하여 산화적 스트레스를 유발하는 물질이다(Choi et al., 2012). 에탄올 대사 과정에서는 ROS가 생성되어 산화스트레스를 유발하며, 과도한 에탄올은 ROS를 제거하는 항산화 시스템을 억제함으로써 지방, 단백질 또는 DNA와 같은 생체 분자에 산화 손상을 유발하여 세포를 손상시킨다(Albano, 2006; Koch et al., 2004). 본 연구에서는 오리나무 잎 추출물(AJL)에서 알코올(EtOH)로 유발된 산화적 스트레스에 대한 간세포 손상의 보호 효과를 평가하기 위해 HepG2/2E1 세포에서 EtOH와 AJL 및 대조군silymarin을 각각 처리한 후 세포생존율을 평가하고 세포독성이 없는 범위를 설정하여 활성산소종 생성량, 항산화 관련 지표(DPPH, ABTS, MDA, GSH) 및 간 손상 지표(AST 및 ALT)를 측정하였다. 알코올에 대한 간 보호 효과에서는 알코올만 처리한 군의 세포생존율이 53.8%로 감소하였으나 AJL을 함께 처리 군에서 세포생존율이 85.1%의 유의적인 증가로 간 보호효과를 확인하였다. 다음으로 AJL에서 세포 내 ROS 생성 억제능은 에탄올 처리군에서 정상군에 비해 유의적으로 ROS 생성이 증가하였으나 AJL 농도별 처리시 정상군 수준으로 ROS 생성을 현저하게 감소시켰다. MDA 함량은 에탄올 처리군에서 무처리군에 비해 유의적으로 증가하였으나 AJL 처리시 농도 의존적으로 에탄올 처리군에 비해 유의적인 차이를 보이며 MDA 함량을 감소시켰다. GSH 함량은 에탄올 처리군에서 정상군보다 유의적으로 함량이 감소하였으나 AJL 농도별 처리군 모두 에탄올 처리군에 비해 GSH 함량을 증가시켰다. 또한 간손상 지표로 활용되는 AST 및 ALT 활성 변화 확인 시, 에탄올 처리에 따른 간세포 손상군에 비하여 AJL 처리군에서는 농도 의존적으로 현저하게 감소시켰으며, 대조군silymarin과 비교하여 유사한 감소된 결과를 관찰하였다. 이상의 결과로부터 종합해 볼때AJL은 간손상에 대한 보호 및 간손상 억제 가능성을 기대할 수 있으며, 간기능 개선 효과에 대한 건강기능식품개발의 기초자료로서 활용될 수 있을 것이라 사료된다.

Alcoholic liver disease (ALD) is a significant risk factor in the global disease burden. The stem bark of the Betulaceae plant Alnus japonica, which is indigenous to Korea, has been used as a popular folk medicine for hepatitis and cancer. However, the preventive effect of Alnus japonica leaf extracts on alcohol-related liver damage has not been investigated. The objective of this study was to investigate the hepatoprotective effects of the extracts of Alnus japonica leaf (AJL) against ethanol-induced liver damage in HepG2/2E1 cells. Treatment with AJL significantly prevented ethanol-induced cytotoxicity in HepG2/2E1 cells by reducing the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). This protective effect was likely associated with antioxidant potential of AJL, as evidenced by the attenuation of reactive oxygen species (ROS) and malondialdehyde (MDA) production and restoration of the depleted glutathione (GSH) levels in ethanol-induced HepG2/2E1 cells. Our findings suggest that FCC might be considered as a useful agent in the prevention of liver damage induced by oxidative stress by increasing the antioxidant defense mechanism.

본 연구에서는 매실나무(Prunus mume, P. mume) 가지 추출물의 항산화, 항염, 항균 활성 및 유효성분을 연구하였다. 매실나무 가지의 ethyl acetate (EtOAc) 분획물에서 noreugenin (1), naringenin (2), prunin (3), procyanidin A2 (4) 및 epiafzelechin-(2β→O→7, 4β→8)-epicatechin (5)의 5개 화합물을 분리하여 NMR 스펙트럼을 포함한 분광 데이터를 기반으로 화학 구조를 동정하였다. DPPH 및 ABTS⁺ 라디칼을 이용한 항산화 실험에서 추출물, EtOAc 및 n-butanol (BuOH) 분획물과 분리된 화합물 4, 5는 강력한 라디칼 소거 활성을 보였다. RAW 264.7 대식세포를 이용한 항염 활성 실험 결과, n-hexane (Hex), EtOAc 분획물 및 분리된 화합물 1 ~ 5는 세포 독성 없이 농도 의존적으로 nitric oxide (NO)의 생성을 억제하였다. 또한, 추출물과 n-Hex, EtOAc 및 n-BuOH 분획물은 Staphylococcus epidermidis 및 Cutibacterium acnes에 대하여 항균 활성을 보였다. 이상의 연구 결과를 바탕으로 매실나무 가지 추출물, 용매 분획물 및 분리된 화합물은 항산화, 항염 및 항균 효과를 갖는 천연 화장품 소재로 적용 가능할 것이라 사료된다.

In this study, we investigated anti-oxidative, anti-inflammatory and anti-bacterial constituents from the extract of Prunus mume (P. mume) branches. Five phytochemicals were isolated from the ethyl acetate (EtOAc) fraction of P. mume branches; noreugenin (1), naringenin (2), prunin (3), procyanidin A2 (4) and epiafzelechin-(2β→O→7, 4β→8)-epicatechin (5). The chemical structures of isolated compounds were elucidated based on the spectroscopic data including NMR spectra as well as comparison of the data to the literature values. Upon the anti-oxidative studies by DPPH and ABTS⁺ radicals, potent radical scavenging activities were observed in the extract, EtOAc, n-butanol (BuOH) fractions and isolated compounds 4, 5. In the anti-inflammatory tests using RAW 264.7 macrophages, the n-hexane (Hex), EtOAc fractions and compounds 1-5 inhibited production of nitric oxide (NO) without causing cell toxicity. Also, the extract, n-Hex, EtOAc and n-BuOH fractions showed anti-bacterial activities against Staphylococcus epidermidis and Cutibacterium acnes. Based on these results, it was suggested that the extract, solvent fractions and phytochemicals from P. mume branches could be applicable as natural source for cosmetic ingredients.

The COVID-19 pandemic is not over despite the emergency use authorization as can see recent COVID-19 daily confirmed cases. The viruses are not only difficult to diagnose and treat due to random mutations, but also pose threat human being because they have the potential to be exploited as biochemical weapons by genetic manipulation. Therefore, it is inevitable to the rapid antibody-based therapeutic platform to quickly respond to future pandemics by new/re-emerging viruses. Although numerous researches have been conducted for the fast development of antibody-based therapeutics, it is sometimes hard to respond rapidly to new viruses because of complicated expression or purification processes for antibody production. In this study, a novel rapid antibody-based therapeutic platform using single B cell sorting method and mRNA-antibody. High immunogenicity was caused to produce antibodies in vivo through mRNA-antigen inoculation. Subsequently, antigen-specific antibody candidates were selected and obtained using isolation of B cells containing antibody at the single cell level. Using the antibody-based therapeutic platform system in this study, it was confirmed that novel antigen-specific antibodies could be obtained in about 40 days, and suggested that the possibility of rapid response to new variant viruses.

Rapid, early, accurate detection and identification of the various pathogenic agents associated with the development of biological weapons is critical in preventing loss of life and limiting the impact of these organisms when used against civilian or military targets. The aim of this study was to produce a system for the simple, rapid, accurate and simultaneous detection and identification of Ricin, Botulinum toxin B and Staphylococcal enterotoxin B as a proof of principle for developing field appropriate reverse transcription loop-mediated isothermal amplification systems for the accurate identification of potential biological threats. These systems were designed to facilitate the identification of potential threats even in remote or resource-limited locations.

Objective: This study examined the mediating effect of mother's parenting attitudes on the relationship between mother's parenting stress and respect for children's rights. Methods: The questionnaires were answered by 287 mothers with children aged 1 to 5 attending child-care centers in Gyeonggi-do, South Korea. The data was analyzed using descriptive statistics, Pearson correlation, and Structural Equation Model. Results: First, parenting stress did not directly affect respect for children's rights. Second, the indirect effect of the mother's parenting stress on respect for children's rights through affectionate parenting attitudes was significant. Third, it was found that parenting stress indirectly affects respect for children's rights through a rejection parenting attitude. Conclusion/Implications: In this study, it was found that mother's parenting stress indirectly affected respect for children's rights through parenting attitude. Based on this result, parent education and programs need to be developed to increase respect for children's rights.

산성광산배수 처리방법은 적극적 처리방식과 소극적 처리방식이 일반적으로 사용되고 있으며, 이때 발생되는 부산물인 슬러지는 국내에서 약 5천 톤/년으로 발생하고 있다. 본 연구는 적극적 처리방식 중 물리·화학적 처리방식으로 정화 후 발생되는 슬러지의 특성을 조사하여 재활용 가능여부를 검토하기 위함이다. 5개소(D, H, S, T, Y) 수질정화시설의 슬러지의 특성을 물리·화학적 분석을 통해 검토하였다. 그 결과 pH는 pH 5.86 ~ pH 7.89로 측정되었고, 수분함량은 51 % ~ 82 %로 분석되었으며, 입자크기는 대부분 25 ㎛보다 작은 미립자로 구성되었음을 확인할 수 있었다. ICP-OES를 이용한 슬러지 내 무기물질 분석결과, Al, Fe, Mn의 농도범위는 각각 1,189 mg/kg ~ 129,344 mg/kg, 106,132 mg/kg ~ 338,011 mg/kg, 3,472 mg/kg ~ 11,743 mg/kg로 조사되어 고농도로 존재함을 확인 할 수 있었다. 그 외 무기물질 중 중금속류에 대해서는 T-슬러지는 As와 Zn, D-슬러지는 Cd, H-슬러지는 Ni, S-슬러지는 Zn, Y-슬러지는 Cd의 농도가 토양오염우려기준을 초과하였다. 또한 슬러지의 용출 특성을 알기위해 폐기물 용출시험(KSLT) 및 TCLP 시험을 진행하였다. 슬러지 재활용시 용출되어 지하수에 미치는 영향 확인을 위해 지하수 수질기준(생활용수) 20개 항목에 대하여 수행하였다. 용출시험결과 특정유해물질 16개 항목에서 모두 불검출로 확인되었으며, 일반항목 4개 항목에 대해서는 모두 생활용수 기준치 이내로 만족하였다. XRD, SEM-EDS의 분석결과, 슬러지는 주로 방해석, 석영의 패턴을 보였으며, 높은 Fe, O의구성비율로철수산화물이높은비중을차지하는것으로보였다. 이를 통해서 비매체접촉형 방식의 재활용의 가능성이 있을 것으로 판단된다.

Acid mine drainage(AMD) treatment is classified as both passive and active treatment. During the treatment, about 5,000 tons of neutralization sludge is generated as a by-product per year in Korea. This study was conducted to evaluate the characteristics of sludge generated from physico·chemical treatment processes as an active treatment from 5 different sources (D, H, S, T, Y) and the possibility of the sludges being recycled. The sludges have a pH range of 5.86 ~ pH 7.89, and a water content range of 51% ~ 82%. Most of particle sizes were less than 25 ㎛. In analysis of inorganic elements, the concentration of Al, Fe, and Mn were between 1,189 mg/kg ~ 129,344 mg/kg, 106,132 mg/kg ~ 338,011 mg/kg, and 3,472 mg/kg ~ 11,743 mg/kg, respectively. The concentration of As and Zn in sludge-T, Cd in sludge-D, Ni in sludge-H, Zn in sludge-S, and Cd in sludge-Y exceeded the soil contamination standards of Korea. The results from 2 separate kinds of leaching test, the Korea Standard Leaching Test(KSLT) and Toxicity Characteristic Leaching Procedure(TCLP), showed that all the sludges met the Korea groundwater standards. From the XRD and SEM-EDS analysis, the peaks of calcite and quartz were found in the sludges. The sludge also had a high proportion of Fe and O, and the majority of the composition was amorphous iron hydroxide.

Although Due to industrial development and urbanization, the number of schools closing due to a decrease in the school-age population is increasing due to the phenomenon of relocation from farming and fishing villages. Closing schools are used as social and cultural facilities, or they are used to generate income by providing education and experiences. Agro-healing is an activity that promotes psychological, social, and physical health by using rural resources. By reflecting the Agro-healing in the services operated by the closed school, the perception of the provision of the Agro-healing service was investigated as a way to provide a therapeutic service to visitors and to increase the utilization of the closed school. The questionnaire consisted of 10 questions, a total of 5 questions related to demographic information, a total of 5 questions related to the perception of agro-healing activities in closed school facilities. As a result, 347 people participated in the survey. The higher the awareness of agro-healing, the need for a agro-healing expert, the satisfaction with the use of rural closed school facilities, and the willingness to participate in agro-healing activities, the higher the awareness that the provision of agro-healing services was necessary by the state. Theses results are expected to be useful as basic to data to solve the diverse limitation in rural closed school and agro-healing activities.

본 연구에서는 경기도내 유통되고 있는 심해성 어류 50건을 대상으로 수은, 메틸수은의 오염도 및 셀레늄의 함량을 알아보았다. 금아말감법의 수은분석기, ICP-MS를 사용하여 측정하였으며 각 항목별 평균함량은 수은 0.7647 mg/kg (0.0182-5.3620), 메틸수은 0.0764 mg/kg (0.0096-0.8750), 셀레늄 0.4728 mg/kg(0.1075-3.5100)으로 메틸수은은 50건 모두 기준규격(1.0 mg/kg) 이하로 나타났다. 셀레늄은 수은과 결합하여 수은의 독성을 감소시키는 것으로 알려져 있으며, 본 연구과제에서는 일일평균섭취량이 3.3 ㎍/kg으로 일일권장량보다 낮은 수치였다. 유해물질인 수은과 메틸수은은 JECFA에서 설정한 PTWI의 5.7%, 1.8%로 조사되었다. 따라서 도내에서 유통되는 심해성 어류의 수은, 메틸수은과 같은 위해중금속은 안전한 것으로 나타났지만 지속적 모니터링이 필요하다고 판단된다.

This study aimed to determine mercury (Hg), methylmercury (MeHg), and selenium (Se) levels in deep-sea fishes distributed in Gyeonggi-do, South Korea. Concentrations of Hg, MeHg, and Se were measured by using a mercury analyzer and Inductively Coupled Plasma - Mass Spectrometry (ICP-MS). The average content (mg/kg) in the seafood samples was as follows: Hg, 0.7647 (0.0182-5.3620), MeHg, 0.0764 (0.0096-0.8750), and Se, 0.4728 (0.1075-3.5100). All the levels of MeHg were below the recommended standards of the Ministry of Food and Drug Safety i.e., <1.0 mg/kg. Recent studies have shown that Se prevents Hg toxicity. The average daily intake in humans was 3.3 ㎍/kg, which was lower than the recommended amount (50-200 ㎍/person/day). The weekly intake of Hg and MeHg was calculated to be 6.07% and 1.90%, respectively, of the provisional tolerable weekly intake (PTWI). This study showed that the weekly intake of Hg and MeHg from abyssal fish was less than the PTWI recommended by the Joint FAO/WHO expert committee on food additives. Therefore, the levels reported in this study are presumed to be adequately safe.

Objective: This study aims to investigate the perception and demand of child care teachers regarding the support project for part-time substitute teachers in Busan. Methods: A survey was conducted on 6,141 childcare teachers participating in the Busan part-time substitute teacher support project, and the data were analyzed using the SPSS 25.0 program. Results: First, an examination of the perception of part-time substitute teacher support projects based on the type of daycare center revealed significant differences in all aspects, except for whether they choose to reapply. Second, an analysis of the demand for part-time substitute teacher support projects, categorized by the type of daycare center, indicated significant differences. Conclusion/Implications: The findings of this study furnish valuable insights for the equitable and effective implementation of the part-time substitute teaching assistant support project, taking into account the distinct characteristics of various daycare centers. Additionally, the results offer essential foundational data to guide the strategic direction of the part-time substitute teaching assistant support project.

본 연구에서는 복숭아혹진딧물의 포식 기생자인 콜레마니진디벌의 기능반응을 조사하였다. 이산화탄소 농도별(400, 600, 1000ppm) 복숭아혹진딧물 밀도를 달리하여(2, 4, 8, 16, 32, 64, 128마리) 콜레마니진디벌 한 마리를 24시간 동안 노출시켰다. 각 이산화탄소 처리에서 콜레마니진디벌은 제 3 유형의 기능반응을 보였다. 600 ppm (0.015 day)과 1000 ppm (0.014 day)에서 추정된 처리시간은 400 ppm에서 추정된 결과(0.017 day)보다 짧았다. 이산화탄소 농도별 복숭아혹진딧물 기생률은 유사한 특징을 나타내었다. 가장 높은 기생률은 400, 600, 1000 ppm에서 복숭아혹진딧물 16, 32, 32마리에 대해 0.57, 0.61, 0.70이었다. 이산화탄소 농도 증가는 콜레마니진디벌의 기능반응에서 공격율에는 영향을 주지 않았지만 처리시간에는 영향을 주었다.

In this study, we investigated the functional response of aphid parasitoid, Aphidius colemani Viereck (Hymenoptera: Braconidae), on the green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae). Three carbon dioxide concentrations (400, 600, and 1000ppm) and seven host densities (2, 4, 8, 16, 32, 64, and 128) were used during a 24-h period. A type III functional response for A. colemani was fit separately for each CO₂ concentration. The estimated handling time (Th) under elevated CO₂ (600 ppm and 1000 ppm, 0.015 and 0.014 day) was shorter than that under ambient CO₂ (400 ppm, 0.017 day). The proportion of aphids that were parasitized showed the similar characteristic curve under three CO₂ concentrations. The highest parasitized rates for A. colemani were 0.57, 0.61, and 0.70 at 16, 32, and 32 aphid density under 400, 600, and 1000ppm, respectively. Although handling time of A. colemani was influenced by elevated CO₂ concentrations, the attach rate was not changed much.

Although user satisfaction and activation are noting new, factors related to user emotion have been a part of the important subject shared by most people for management. But few studies have known in culture and welfare facilities using closed rural schools. The samples were collected through self-completed a questionnaires, a total of 322 users data were identified by SPSS 25.0 and frequency and descriptive analysis, correlation analysis and multiple regression analysis were performed. The main results are as follows: 1) General user satisfaction of culture and welfare facilities using closed rural schools reach a total or 8.52 points(out of a total of 10 points), 2) significant factors related to user satisfaction are comparative satisfaction, recognition of contribution to the local economy, age, job. A key insight from these results is that most users are satisfied with the culture and welfare facilities using closed rural schools. And relationship between user satisfaction and a variety of variables indicates the essential for differentiation and utilization of services. It is necessary to implement several practical and political strategies taking the context and the needs of users as a way of enhancing the urban and rural welfare services.

본 연구에서는 광나무(Ligustrum japonicum) 열매 발효 추출물의 항염 및 항산화 효능을 비발효 추출물과 비교 분석하였다. 광나무 열매의 발효는 제주 자리돔(Chromis notata) 내장에서 분리한 Latilactobacillus curvatus (L. curvatus) 및 Weisella minor (W. minor) 균주를 이용하였으며, 각각의 발효 추출물(LJF-LC 및 LJF-WM)의 수율은 40.5 ~ 46.0%로 비발효 추출물(LJF)의 29.5% 보다 높게 나타났다. Lipopolysaccaride(LPS)로 자극된 RAW 264.7 대식세포를 이용한 nitric oxide (NO) 생성 억제 활성 실험 결과, 발효 추출물인 LJF-WM이 세포 독성 없이 농도 의존적으로 NO의 생성을 저해시키는 효과가 우수함을 확인하였다. 또한 DPPH 및 ABTS⁺ 라디칼 소거 활성 실험 결과, 발효 추출물의 라디칼 소거 활성이 비발효 추출물과 유사하게 나타났으며, 발효 추출물 LJF-WM은 과산화수소(H₂O₂)로 유도된 세포 손상에 대한 세포보호 효과를 보였다. 광나무 열매의 주성분인 salidroside의 함량을 HPLC를 이용하여 분석한 결과, 발효 추출물 LJF-LC에서 15.6 mg/g, LJF-WM에서 13.9 mg/g으로 확인되어 비발효 추출물(12.0 mg/g) 보다 함유량이 높게 분석되었다. 이상의 연구 결과를 바탕으로 광나무 열매 발효 추출물은 항염 및 항산화 효과를 갖는 천연 화장품 소재로써 활용 가능할 것이라 사료된다.

In this study, the anti-inflammatory and anti-oxidative activities were compared for the extracts of non-fermented Ligustrum japonicum fruits (LJF) and fermented counterparts. U se of Latilactobacillus curvatus (L. curvatus) and Weissella minor (W. minor), isolated from the Jeju Chromis notata, as fermented strains led to the extracts of LJF-LC and LJF-WM in this experiment. The yield of each fermented extract (LJF-LC and LJF-WM) was 40.5 ~ 46.0%, higher than 29.5% of non-fermented extract (LJF). As a result of an activity experiment using RAW 264.7 macrophages stimulated by lipopolysaccaride (LPS), it was confirmed that LJF-WM, a fermented extract, has an excellent effect of inhibiting NO production in a concentration-dependent manner without cytotoxicity. Upon the screening of DPPH and ABTS⁺ radical scavenging activities, the fermented LJF-LC and LJF-WM showed comparable to the non-fermented LJF. In the study of cell protection effect using HaCaT keratinocytes damaged by hydrogen peroxide (H₂O₂), the fermented LJF-WM indicated protective effect against oxidative stress. In addition, quantitative analysis of a major constituent salidroside by HPLC indicated about 15.6 mg/g for the LJF-LC and 13.9 mg/g for the LJF-WM, which were higher than that of non-fermented LJF (12.0 mg/g). Based on these results, it was suggested that the fermented extract from L. japonicum fruits could be used as a natural cosmetics material with anti-inflammatory and anti-oxidative effects.

본 연구에서는 토양 내 비소 및 수은의 안정화제로 황산칼슘비료의 적용 가능성을 검토하였다. 아울러 황산칼슘비료의 물리적 특성(입자상, 미분상, 용액상)에 따른 비소 및 수은의 안정화 특성을 상추 재배 포트실험으로 비교?검토하였다. 34일 간의 상추재배를 통해 확인한 비소 및 수은의 전이감소 효과는 대체적으로 70% 이상인 것으로 나타나 안정화제로서의 적용성을 확인하였다. 다만, 용액상 안정화제 처리조건에서 성장한 상추의 생체량은 대조구의 46% 수준으로 가장 낮았는데, 이는 안정화제로부터 유래된 영양물질의 유효도가 극단적으로 높아 오히려 식물체 성장을 저해한 것으로 판단되었다. 토양 내 비소 및 수은의 분획특성 확인결과 수은에서만 존재형태의 변화가 크게 나타났다. 수은은 안정화 처리된 토양에서 원소수은의 감소와 잔류형/황화물 형태의 증가가 확인되었는데, 이러한 경향은 용액상 > 미분상 > 입자상의 순서로 나타났다. 본 연구를 통해 대형 교반장비의 진입이 어려운 농경지에서는 용액상 처리제의 살포만으로 안정화 효과를 얻을 수 있음을 확인하였다. 다만, 높은 영양물질 유효도로 인해 염해토양의 특성을 보일 수 있으므로, 투여량 조절을 통해 농작물 위해를 사전 제어할 필요가 있다.

In this study, we investigated the feasibility of calcium sulfate fertilizer as a stabilizing agent for As and Hg contaminated farmland soil and its stabilization characteristics in 3 different physical forms (particulate, powder, and solution) through a pot experiment including 34 days of lettuce growth. As and Hg contents of the lettuce grown in the stabilized soils were decreased by at least 70%. However the lettuce yield of the soil stabilized with the solution agent was decreased by 46% due to the overabundance of the nutrients from the solution agent. Thus, if a solution-type agent is planned for agricultural farmland soil stabilization, additional tests for optimal dosage are needed to preserve vegetation growth. In Hg fractionation, a lower concentration of elemental fractions and a higher concentration of residual/sulfide fractions were identified in the soils stabilized with the solution, powder, and pariculate agents in descending order while there were no significant changes in As fractionation. Overall results suggest that calcium sulfate fertilizer can be used as a stabilizing agent, and a solution-type agent could be used when the operation of heavy machinery for the soil stabilization process is impossible.

최근 국제해사기구(IMO)를 비롯한 국제사회에서 선박의 대기오염 배출 규제를 강화하고 있으며, 배기가스 배출을 줄이기 위한 친환경 선박 개발이 활발하게 이루어지고 있다. 그중에서도 풍력 보조 선박추진 시스템 중 하나인 로터 세일(Rotor Sail, RS)이 다시금 주목받고 있다. RS는 선박 데크에 설치되는 원통형 실린더 장치로 마그누스 효과를 사용하여 유체 동역학적 양력을 생성하는 장치이다. 이는 차세대 친환경 보조 추진 기술 중 하나이며, RS 적용 선박을 개발한 Enercon 사(社)에서는 약 30% 이상의 연료 절감이 가능하다고 발표했다. 본 연구에서는 다중 RS를 선박에 설치할 경우 RS 간격 및 배열 형태와 같은 최적의 설치 조건을 선정하고자 하였으며, RS 배열에 따른 유동특성을 확인하기 위하여 AR(Aspect Ratio) = 5.1, SR(Spin Ratio) = 1.0 및 로터세일 지름과 엔드 플레이트 지름 비(D_e/D)= 2.0 로 고정하고 자유 유속 U = 5 m/s로 풍향은 +y 축 단방향에 대한 조건만 고려하였다. 배열 조건은 횡방향 거리는 +x 축 방향으로 3D ~ 15D까지 3D 간격으로 총 5가지 조건을, 종방향 거리는 +y 축 방향으로 5D ~ 25D까지 5D 간격으로 총 5가지 조건을 설정하였으며, 사각 형태(□)와 마름모 형태(◇) 배열에 따른 양력계수(C_L), 항력계수(C_D)와 공기역학적 효율(C_L/C_D)을 비교하였다. 결과적으로 종방향 간격에 따른 RS의 영향은 크게 차이가 없었으나, 횡방향 간격에 따른 RS 유동특성의 경우 두 RS가 바람 방향에 거의 일치할 때 RS의 상호작용 효과가 가장 크게 나타났다. 배열에 따른 RS 유동특성의 경우, 전방(0°) 방향에서 바람이 불 때 마름모 형태(◇) 배열이 RS 간의 후류 영향을 가장 덜 받는 것으로 나타났다.

Recently, the international community, including the International Maritime Organization (IMO), has strengthened regulations on air pollution emissions of ships, and eco-friendly ships are actively being developed to reduce exhaust gas emissions. Among them, rotor sail (RS), a wind-assisted ship propulsion system, is attracting attention again. RS is a cylindrical device installed on the ship deck, that generates hydrodynamic lift using a magnus effect. This is a next generation eco-friendly auxiliary propulsion technology, and Enercon company, which developed RS-applied ships, announced that fuel savings of more than 30% are possible. In this study, optimal installation conditions such as RS spacing and arrangement type were selected when multiple RSs were installed on ships. AR=5.1, SR=1.0, and D_e/D was fixed at 2.0 according to the RS arrangement, and the wind direction was considered only for the unidirectional +y-axis. Regarding arrangement conditions, five conditions were set at 3D intervals in the +x-axis direction from 3D to 15D and five conditions in the +y-axis direction from 5D to 25D. C_L, C_D and aerodynamic efficiency (C_L/C_D) were compared according to the square(□) and diamond(◇) shape arrangements. Consequently, the effect of RS on the longitudinal distance was not significantly different. However, in the case of RS flow characteristics according to the transverse distance, the interaction effect of RS was the greatest when the two RSs almost matched the wind direction. In the case of the RS flow characteristics according to the arrangement, notably, when the wind blew in the forward (0°) direction, the diamond (◇) arrangement was least affected by the backward flow between RSs.

The purpose of this study was to explore the experiences and future challenges in providing of social service based on agro-healing. The study conducted was a general qualitative research which involved the collection and analysis of experiences shared by four representatives of participating in Gyeonggi-do community service investment pilot project. The data were gathered through individual in-depth interviews, and the findings were thoroughly analyzed to draw meaningful insights. The study revealed three main topics of discussion: "knowing the necessity of entering social services," "thresholds to be crossed to enter social services," and "future tasks". Based on the these results, implications for the development of community social services related to agro-healing were suggested, and the limitations were also discussed.

본 연구에서는 사석지반 충진을 위한 그라우트 주입공법의 설계 및 시공에 대한 일련의 기초 실험을 진행하였다. 먼저 소형 그라우트 주입장치를 설계제작해 25mm 단입도 골재에 수중주입 하였다. 이 축소실험 결과, 그라우트의 압축강도 범위가 20-80MPa 수준일 때, 표면이 깨끗한 자갈을 그라우트로 보강한 개량체의 일축압축강도는 그라우트 자체의 강도에 비해 약 1/6 수준이었다. 하지만, 이 개량체의 강도는 골재 계면의 조건에 따라 크게 감소할 수 있음을 확인하였다. 또한, 개량체용 그라우트의 수중마모 저항성을 평가하였으며, 실험결과 15MPa 이상의 그라우트는 유수에 의한 마모를 고려하지 않아도 되는 것으로 확인 되었다. 마지막으로 25cm 크기의 사석부에 지름 약 1m 높이 1.2m 수준의 대형 구근을 제작해 충전성을 검토하였으며, 이 결과 그라우트의 유동성에 의해 사석 충전성능이 크게 영향 받는다는 것을 알 수 있었다.

A series of experiments were performed to investigate the design and application of a rubble-ground modification method with grout injection. A small-sized injection machine was designed, and the grouts with various mix proportions were injected into 25 mm aggregate using the designed small-sized injection machine. With the compressive strength of the grout ranging from 20 to 80 MPa, the uniaxial compressive strength of the grout-filling bodies with clean gravels was higher than 1/6th of the strength of grouts themselves. However, this fraction may reduce depending on the interface conditions. The erosion resistance of the hardened grout was evaluated, and it was determined that the grout with a strength greater than 15 MPa did not require erosion consideration. Moreover, a full-scale injection test was performed for 25 cm-sized rubbles in cages with a diameter greater than 1 m and a height of 1.2 m to evaluate the filling characteristics of the grout. Results from this test indicated that the grout flowability sensitively influenced the filling characteristics.

덕티드 로켓의 가스발생기에 사용되는 추진제는 연료과농 추진제로서, 일반적인 고체 로켓 추진제에 비하여 과량의 금속연료와 소량의 산화제를 포함한다. 본 논문에서는 연료과농 추진제를 제조하기 위하여 보론 분말과 MgAl(Magnesium-Aluminium Alloy)를 적용하였다. 이 금속연료를 적용한 추진제의 특성을 분석하였고, 이를 통하여 최적의 조성을 연구하였다. 추진제의 연소생성물 분석을 통하여 보론 비드가 아닌 미립의 보론 분말로도 가스발생기용 연료과농 추진제가 가능함을 확인하였다.

The propellants used in the gas generator of the ducted rocket are fuel-rich propellants, which contain an excessive amount of metal fuel and a small amount of oxidizing agent compared to general solid rocket propellants. In this paper, boron powder and MgAl(Magnesium-Aluminium alloy) were applied to produce fuel-rich propellants. The optimum formulation was determined by characterizing these metal fuel-rich propellants. Analysis of combustion products in the gas generators confirmed that the fuel-rich propellants containing fine boron powder itself instead of boron-bead could be useful in gas generators.

In analyzing heavy metals in soil samples, the standard protocol established by Korean Minstry of Environment (KSTM) requires two different pretreatments (A and B) based on soil particle size. Soil particles < 0.15 mm in diameter after sieving are directly processed into acid extraction (method A). However, if the quantity of soil particles < 0.15 mm are not enough, grinding of the particles within 0.15 mm ~ 2 mm is required (method B). Grinding is often needed for some field samples, especially for the soil samples retrieved from soil washing process that contain relatively large-sized soil grains. In this study, two soil samples with different particle size distribution were prepared and analyzed for heavy metals concentrations using two different pretreatment to investigate the effect of grinding. The results showed that heavy metal concentrations tend to increase with the increase of the fraction of small-sized particles. In comparison of the two pretreatments, pretreatment A yielded higher heavy metal concentration than pretreatment B, indicating significant influence of grinding on analytical results. This results suggest that the analytical values of heavy metals in soil samples obtained by KSTM should be taken with caution and carefully reviewed.