Refractory materials, such as molybdenum and niobium, are potential candidates for cladding material due to their high melting temperatures and desirable mechanical properties at higher temperatures than those of zirconium alloys. However, refractory materials have low resistance to oxidation at elevated temperatures. Therefore, this study examined silicide or aluminide surface coatings as protection against rapid oxidation of refractory materials at elevated temperatures for a potential accident-tolerant fuel cladding. Silicide or aluminide layers were formed on refractory metal substrates by using the pack cementation method. The steam oxidation behavior of both coated and uncoated samples was compared by thermogravimetric analysis at 1200°C. The weight changes of the coated samples were greatly reduced than those of uncoated samples. Microstructural analyses demonstrated that the silicide and aluminide layers were oxidized to form a protective surface oxide that prevented rapid oxidation of the refractory substrate at elevated temperatures.

Pleurotus ostreatus is a globally cultivated mushroom crop. Cap color is a quality factor in P. ostreatus. However, cap color can spontaneously mutate, degrading the quality of the mushroom on the market. Early detection and removal of mutant strains is the best way to maintain the commercial value of the crop. To detect the cap color mutant Gonji7ho, molecular markers were developed based on insertion/deletions (InDels) derived from the comparison of mitogenomes of Gonji7ho and Gonji7hoM mushrooms. Sequencing, assembly, and comparative analysis of the two mitogenomes revealed genome sizes of 73,212 bp and 72,576 bp with 61 and 57 genes or open reading frames (ORFs) in P. ostreatus Gonji7ho and Gonji7hoM, respectively. Fourteen core protein-encoding genes, two rRNA, and 24 tRNA with some OFRs were predicted. Of the 61 genes or OFRs in the wild type, dpo, rpo, and two orf139 were missing (or remnant) in the mutant strain. Molecular markers were developed based on the sequence variations (InDels) between the two mitogenomes. Six polymorphic molecular markers could detect the mutated mitochondria by PCR. These results provide basic knowledge of the mitogenomes of wild-type and mutant P. ostreatus, and can be applied to discriminate mutated mitochondria.

Spermatogonial stem cells are self-renewal and differentiate into sperm in post-pubertal mammals. There exists a balance between the self-renewal and differentiation in the testes. Spermatogonial stem cells make up only 0.03% of testicular cells in adult mice. These cells maintain sperm production by differentiating after puberty. Therefore, analyzing the expression of genes associated with spermatogenesis is critical for understanding differentiation. The present study aimed to establish the postnatal period of cells in relation to spermatogenesis. To study the expression of differentiated and undifferentiated marker genes in enriched spermatogonial stem cells, in vitro culture was performed and cells from pup (6–8-day-old) and adult (4-months-old) testicular tissues were isolated. As a result, undifferentiated genes, Pax7, Plzf, GFRa1, Etv5 and Bcl6b , were highly increased in cultured spermaotogonial stem cells compared with pup and adult testicular cells. On the other hands, differentiated gene, c-kit was highly increased in adult testicular cells, Also Stra8 gene was highly increased in pup and adult testicular cells. This study provides a better understanding of spermatogenesis-associated gene expression during postnatal periods.

본 연구는 선진국에서 앞장서서 선포하고 있는 세계적인 추세인 뇌발달에 대한 관심을 바탕으로 한다. 특히 뇌발달의 기초가 되는 영아기 뇌발달에 대한 애착기반 부모교육의 중요성을 제안하였다. 현대의 부모가 편리하고 개별적으로 쉽게 접근할 수 있는 M-러닝 프로그램을 제안하였다. 뇌의 발달은 영아기에 급속도로 이루어진다. 두미발달의 원칙에 의해 출생 시에 머리와 뇌의 크기는 신체의 다른 어떤 부위보다 성인에 가깝다. 영아기 뇌의 발달은 전적으로 생물학적 프로그램에 따른 것이 아니고 환경의 영향에 의해 민감하게 작용한다. 안정된 애착으로 인한 효과적인 우뇌 기능의 발달은 영아가 성장하는 단계에서 최적의 발달을 위한 회복요인이다. 안정된 애착에 의한 양육경험은 영아의 정서적 표현과 두뇌의 신경 화학적 물질에 영향을 주어 사회적, 정서적 행동조절에 긍정적인 영향을 미친다. 결국 두뇌발달의 유발요인은 안정된 애착형성이라고 할 수 있다.

본 연구는 게임이용장애 대학생에 대한 감각자극 기반 미술치료 진단 및 개입 방안에 대하여 살펴보기 위하여 검증된 학술지를 분석하였다. 대학생이 게임이용장애에 취약할 수 있으며, 좀 더 주목해야 할 대상군이다. 게임이용장애자들이 시각적 자극에 매우 민감하므로 그들의 민감성을 고려하여 진단과 개입 프로그램이 개발되어야 한다. 온라인 게임 중독자들은 감각에 통해 받아들인 게임 자극을 뇌에서 적극적으로 분석하고 처리한다. 따라서 감각기반 개입방안들이 적극적으로 고려되어야 하고, 이에 대한 기초연구가 다각적으로 이루어져야 한다. 대학생 게임이용장애 원인을 바탕으로 한 진단과 개입을 위한 투사 그림검사는 자아정체감, 자아탄력성, 성인애착과 나무그림, HTP(집-나무-사람), 우울과 발테그 그림검사(WZT), 대학생활 적응수준과 풍경구성기법(LMT), 가족건강성과 동적가족화(KFD), 스트레스 대처방식과 빗속 사람 그림(PITR), 대인관계, 자아탄력성, 애착과 모자화(Mother and Child Drawing), 자아탄력성과 좋아하는 날씨 그림(FKW), 우울 및 조증, 스트레스 대처수준과 사과 따는 사람 그림(PPAT), 우울 및 불안과 별-파도 그림(SWT)이었다.

In Korea, concrete pavements were first applied to highways in 1981 and as a result of continued increase in length over the past years, 2,592 km of concrete pavement network is currently in service, of which 1,399 km(54%) of concrete pavements is 10 years or older, and 233km(9%) is 20 years or older. The length of concrete pavement sections nationwide has been steadily on the rise every year (EXTRI, 2017). Approximately 54% of current concrete pavement highway network will reach the service life limit in 2025 which means around 660 billion won is needed for future pavement repair project (EXTRI, 2017). Given that concrete pavements beyond design life still have a remaining service life, it is economically advantageous to repair them before reconstruction. Asphalt overlays are a major repair method for older concrete pavements. Depending on the concrete pavement condition, thickness and mixture of asphalt overlays are determined. Service life of asphalt overlays varies by the presence, time and size of cracks in existing concrete pavements and reflecting crack at joints. Temperature change of concrete pavement is among the major reaction parameters of reflecting crack. Reflecting crack develops when asphalt bottom-up cracking by longitudinal shrinkage and expansion due to temperature change of the concrete base layer, top-down cracking by temperature difference between top and bottom of concrete, and shear stress by traffic loading are combined (Baek, 2010). Crack and joint behaviors of concrete pavement vary between the base layer and the concrete surface of composite pavement system, and different conductivity by mixture and thickness of asphalt overlay leads to temperature change of concrete base course. This study measured temperatures of each layer of diverse composite pavements in place on site and analyzed differences in temperature change of concrete base layer depending on mixture and thickness of asphalt overlays. Overlay thickness parameters were 5cm and 10cm, two values most widely used, while mixture parameters were SMA and porous asphalt. Based on temperature change of concrete surface, this study also evaluated the difference of temperature change in concrete base layer with an asphalt overlay on top. Findings from this study are expected to be utilized for studies on mechanism and modeling of reflecting crack in old concrete pavements with asphalt overlays.

1차원 등엔트로피 모델과 통합된 경계층 적분법은 초음속 노즐의 설계과정에서 내열재 표면의 열전달을 예측하는데 효과 적으로 사용되고 있지만 노즐 목과 같이 2차원 효과와 경계층과 노즐 코어유동의 상호작용이 발생하는 지점에서는 경계층 외부유동 해석의 부정확성으로 해석의 정확도가 감소한다. 따라서 본 연구에서는 경계층 적분법을 이용한 열전달 예측의 정 확도를 향상시키기 위해 CFD를 이용하여 2차원 효과와 노즐 코어유동의 상호작용이 고려된 경계층 외부유동 조건을 도출 하고 이를 경계조건으로 하는 해석기법을 개발하였다. 오일러 모델과 SST k-ω 모델을 CFD로 해석하여 경계조건으로 적용 했으며 계산방법을 검증하기 위해 선행문헌의 실험노즐에 대해 해석을 수행하였다. 계산 결과 CFD를 통해 경계층 외부유동 조건을 도출한 해석에서 노즐 열전달의 정확도가 향상되는 것을 확인하였으며 특히 노즐 목 후방과 팽창부에서의 차이가 크 게 나타났다. SST k-ω모델로 도출된 계산결과는 1차원 등엔트로피 모델과 비교 시 팽창부에서 실험결과와의 오차가 16% 감소하였다. 본 연구에서 개발된 해석기법은 향후 로켓노즐의 내열설계에 유용하게 사용될 것으로 평가된다.

One hundred seventy two accessions of safflower, collected in four countries were investigated for their morphological and biochemical characters in 2014. The accessions were categorized into two groups; South-Central (S-C) Asia and South-West (S-W) Asia, and each group was represented the accessions of two countries. Variation in morphological and biochemical characters was observed between two groups of accessions. The average value of seed weight and range of variability were higher in S-C Asia accessions while S-W accessions exhibited the variation in plant height, leaf length and days to flowering. The average value of oleic and total oil content were higher in S-C Asia accessions, and the values were 19.8%, and 231.4 mg.g-1, respectively, while the range of variability for total oil content was higher in S-W accessions. Plant height exhibited a significant positive correlation with days to flowering (r = 0.625**). Palmitic acid had positively correlated with stearic acid (r = 0.282**) and linoleic acid (r = 0.444**). Oleic and linoleic acid showed a strong negative correlation (r = -0.977**). The first three principal components explained 57% of the total variation. Morphological and biochemical variation exist in different groups of accessions could be useful to breeder for developing new safflower cultivars with high oil quantity and quality.

본 연구는 전국의 686개 농가에 대한 설문조사를 통해 농가의 GM 기술과 GM 작물 및 이를 활용한 사료에 대한 인식, 농가의 생산 현황과 속성을 바탕으로 농가의 GM 벼 (쌀)와 GM 사료작물에 대한 기술 수용성을 분석하였다. 개 별적인 농가 속성에 따라 수용 의사가 다르지만, 2개의 GM 기술 수용성 추정에서 공통적으로 GM 기술 수용 의 사를 높이는 변수는 GM 농작물의 필요성에 대한 인식과 잡곡이나 조사료 재배여부로 나타났다. 평균적인 경종 농 가의 경우 7.8% 유의수준에서 농가소득이 47% 증가할 경 우 벼 (쌀)에 대한 GM 기술을 수용하고, 벼 (쌀)를 제외한 사료작물의 경우에는 14.1% 유의수준에서 농가소득이 43% 증가할 때 GM 기술을 수용하는 것으로 분석되었다. 벼 (쌀)와 비교해서 사료 작물은 상대적으로 적은 소득 증가 에도 불구하고 수용 가능성이 나타났다. 그러나 두 가지 경우 모두 통계적 유의성이 5%를 넘어가 신뢰도에 문제가 있다. 앞으로 GM 기술에 대한 신뢰성이 높아짐에 따라 CVM에서 발생하는 가상적 편의가 줄어든다면 통계적 유 의성이 높아질 것으로 기대되므로 이에 대한 추가 연구가 필요하다.

사우디아라비아 북부지역에서 수집된 홍화 총 100자원에 대 한 총폴리페놀 함량 및 항산화 활성을 평가하여 항산화활성이 높은 홍화자원을 선발하고자 연구를 수행하였으며 그 결과는 다음과 같다. 1. 총 100자원의 홍화유전자원에 대한 총폴리페놀 함량은 14.2 ± 0.41 μg GAE mg−1dw에서 81.6 ± 1.56μg GAEmg−1dw 까지 분포하였다. DPPH 라디컬 소거능은 1.6 ± 0.07 μg ASC mg−1 dw에서 14.1 ± 0.23 μg ASCmg−1 dw까지 활성을 나 타냈다. ABTS 활성은 34.5 ± 0.70 μg Trolox mg−1 dw에서 156.5 ± 3.06 μg Trolox mg−1 dw까지 평가되었다. 항산화활성 을 측정한 DPPH와 ABTS 활성간에는 상당한 유의성(r = 0.954**)을 보였다. 2. 홍화자원 100자원의 총폴리페놀 함량 및 항산화활성 결 과값에 대한 상호관계를 분석하여 활성이 높은 그룹(Group1)을 얻었다. Group1에 포함된 8개의 홍화자원은 나머지 그룹에 속한 자원들에 비해 항산화활성이 높았으며, 이중 K185841, K185879, K185863은 Group1내의 다른 자원들보다도 항산화 활성이 상당히 높아 홍화육종이나 기능성물질연구에 좋은 소 재가 될 것으로 사료된다.

The current study was designed to investigate the effect of Red ginseng extract on development of colonic aberrant crypt foci (ACF) induced by 1,2-dimethylhydrazine (DMH) in male F344 rats. Five-week old animals received subcutaneous injections of DMH (30 mg/kg body weight) four times, for a period of two weeks in order to induce ACF. The animals were divided into groups fed a diet containing red ginseng extract at three different doses (0.5, 1.0, and 2.0%), respectively. Animals were evaluated for the total number of ACF and total aberrant crypts (AC) per colon detected from methylene blue-stained rat colon. ACF formation was observed in animals in the DMH-treated group. Four-time treatment with DMH induced mean 265.8±48.3 ACF/colon composed of a total of 608.8±110.9 aberrant crypts AC/colon. The numbers of ACF and AC induced by DMH were decreased to 204.4±29.3 and 464.7±70.3 by treatment with 0.5% red ginseng extract. In addition, the number of large ACF (≥4 AC/ACF) was suppressed from 39.9±10.6 ACF/colon in control to 28.5±5.3 ACF/colon in 0.5% red ginseng extract. These results suggested that red ginseng extract exerted a chemopreventive effect on DMH-induced colon cancer by inhibiting development of ACF and AC in F344 rats.

Since high-level radioactive wastes contain long-lived nuclides and emit high energy, they should be disposed of permanently through a deep geological disposal system. In Korea, the first (2016.07) and the second (2021.12) basic plans for the management of high-level disposal systems were proposed to select sites for deep geological disposal facilities and to implement business strategies. Leading countries such as Finland, Sweden and France have developed and applied safety cases to verify the safety of deep geological disposal systems. By examining the regulatory status of foreign leading countries, we analyze the safety cases ranging from the site selection stage of the deep geological disposal system to the securing of the permanent disposal system to the investigation, analysis, evaluation, design, construction, operation, and closure. Based on this analysis, we will develop safety case elements for long-term safety of deep geological disposal systems suitable for domestic situation. To systemically analyze data based on safety cases, we have established a database of deep geological disposal system regulations in leading foreign countries. Artificial intelligence text mining and data visualization techniques are used to provide database in dashboard form rather than simple lists of data items, which is a limitation of existing methods. This allows regulatory developers to understand information more quickly and intuitively and provide a convenient interface so that anyone can easily access the analyzed data and create meaningful information. Furthermore, based on the accumulated bigdata, the artificial intelligence learns and analyzes the information in the database through deep learning, and aims to derive a more accurate safety case. Based on these technologies, this study analyzed the legal systems, regulatory standards, and cases of major international leading countries and international organizations such as the United States, Sweden, Finland, Canada, Switzerland, and the IAEA to establish a database management system. To establish a safety regulation base suitable for the domestic deep geological disposal environment, the database is provided as data to refer to and apply systematic information management on regulatory standards and regulatory cases of overseas leading countries, and it is expected that it will play a key role as a forum for understanding and discussing the level of safety of deep geological disposal system among stakeholders.

The number of dismantled nuclear facilities is increasing globally. Dismantling of nuclear facilities generates large amount of waste such as concrete, soil, and metal. Concrete waste accounts for 70% of the total amount of waste. Since hundreds of thousansds of tons of concrete waste generated, securing technology of reduction and recycling of waste is emerging as a very important issue. The objective of this study is to synthesize geopolymer using inorganic materials from cement fine powder in concrete waste. Dismantled concrete waste contains a large amount of calcium silicate hydrate(C-S-H), Ca(OH)2, SiO2, etc., which is an inorganic material required for the synthesis of geopolymer. SiO2 affects the compressive strength of the geopolymer and Ca(OH)2 affects the curing rate. A high concentration of alkali solution is used as an alkali activator, and alkali activator is necessary for the polymerzation reaction of metakaolinite. The experiment consists of three steps. The first step is to react with concrete waste and hydrochloric acid to extract ions. In the solid after filtration, SiO2 and Al2O3 are composed of 84.10%. It can be used instead of commercial SiO2 required for the synthesis of geopolymer. The second step is to add NaOH up to pH 10, impurities can be removed to extract Ca(OH)2 with high purity. The final step is to add NaOH up to pH 13, and Ca(OH)2 extraction. The alkali solution generated after the last reaction can be recycled into an alkali activator during the synthesis of the geopolymer. If dismantled concrete waste is recycled during geopolymer synthesized, the volume reduction rate of dismantled concrete waste is more than 50%. If you put the radioactive waste in the recycled solidification materials synthesis from concrete waste by dismantling of nuclear facilities, it is possible to reduce the amount of waste generated and disposal costs.