본 논문에서는 1673K에서 소결한 PSZ/Ni 복합재에 대한 종 탄성계수, 파괴강도, 파괴에너지 등의 기계적 특성을 평가하기 위해, 개량형 소형펀치시험을 행한 결과에 대해 논의한다. 또한 파면관찰과 AE법을 통해 이들 재료의 고온환경에서의 미시파괴과정도 조사하였다. 시험온도는 293K, 1073K, 1273K, 1473K의 4종류로 하였으며, PSZ/Ni 복합재료의 체적 조성비도 80/20, 60/40, 40/60, 20/80의 4종류이다. 이들 실험결과로부터, 1073K이상의 고온에서 Ni 함량이 60%인 PSZ/Ni 복합재가 파괴강도 및 파괴에너지가 가장 우수한 것을 알았다. 파면관찰에 의하면 이 재료의 조성비에서 파고거동이 취성으로부터 연성으로 천이하는 것을 확인할 수 있었다.

The purpose of this study was to investigate the effect of a single treatment o voltage pulsed current (HVPC) on edema reduction. Hind limbs of 23 anesthetized were injured by dropping a 400 g weight onto the plantar aspects of the feet. On limb of each frog was randomly selected to receive 30 minutes of continuous, 12 cathodal HVPC at voltages 10 % less than motor threshold levels. Limb volumes measured by water displacement before trauma and at predetermined intervals hours posttrauma. Sources of significant differences were determined by t-test HVPC significantly (p<0.05) reduced edema formation. We hypothesize that HVP also be effective in controlling edema formation after impact injuries in humans.

Electrohydrodynamic Atomization 급냉응고장치를 이용하여 고순도 실리콘 미세분말을 제조하여 투과전자현미경으로 미세조직과 그 응고상을 조사한 결과 직경이 60nm 이하인 분말에서 비장질상이 발견되었다. 비정질 실리콘의 원자구조를 분석하기 위하여 비정질 분말에서 얻은 전자회절 데이타를 이용하여 radial distribution function을 계산하여 해석한 결과, 실리콘의 결정구조인 다이아몬드 입방격자에서 발견되는 기본적 정사면체 배열이 비정질 실리콘의 2번째 근접원자간 거기까지 유지됨을 알 수 있었으며 이로부터 비정질 실리?이 단범위 규칙성을 갖는 tetrahedrally coordinated random network 원자배열로 이루어짐을 알았다.

인삼의 ehtanol 추출물과 영지 열수추출물 및 영지 crude polysaccharide가 유산균 생육에 미치는 효과를 L. casei IAM 1643과 S. thermophilus KCTC 2185를 대상으로 하여 조사하였다. 인삼추출물에는 탄수화물 60.7%, 단백질 27.5%, 영지추출물에는 단백질 46.4%, 탄수화물 35.9%가 함유되어 탄수화물과 단백질이 일반성분의 대부분을 나타내었으며, 영지 crude polysaccharide의 총당함량과 총단백질함량은 각각 47.2%와 15.2%이었다. 인삼 추출물에는 arginine과 tryptophan의 2종의 아미노산이 함유된 것으로, 영지추출물에는 이들 외에도 alanine, lysine, serine 등 모두 11종의 아미노산이 함유된 것으로 확인되었다. 인삼추출물과 영지추출물 및 영지 crude polysaccharide를 0.1%, 0.2%, 0.4%씩 TG배지에 첨가하여 유산균을 배양하였을 때 이들을 첨가하지 않은 대조구에 비하여 모두 뚜렷한 생육증진 효과를 나타내었다. 특히 그 효과는 인삼추출물은 L. casei의 경우에, 영지추출물은 S. thermophilus의 경우에 더욱 뚜렷하게 나타났으며 첨가량이 증가할수록 그 효과도 증가하였다. 인삼 및 영지추출물에서 분석된 유리 아미노산중 arginine, lysine 등은 L. casei의 경우에 생육증진 효과를 나타내었으며, lysine, serine, arginine, glutamic acid 등은 S. thermophilus의 경우에 효과를 나타내었다.

The fatty acid, all cis-δ5,11,14-C20:3, in the Gingko nuts oils, was isolated and, purified by urea-adduct method, silver ion silica gel chromatography and HPLC equipped with reversed phase μ-Bondapak C18 column. Its structural elucidation was conducted by IR and 1H-, 13C-NMR technique. The fatty acid composition of seed oils mainly consists of linoleic acid(37.73%), vaccenic acid(18.30%), oleic acid(15.18%), palmitic acid(3.37%), palmitoleic acid(3.37%) and δ5 NMDB fatty acids(8.50%) in which all cis-δ5,11,14-C20:2 predominates.

Polyester, polyacrylics, nylon과 cotton을 이용해 이들의 막지지천으로의 사용가능성을 조사하였다. 압축률, membrane embossing, 유량과 물리적·화학적 특성 등을 고려한 결과 50 번수의 polyester가 막지지천으로 적당함을 알았다. 이 polyester를 막지지천으로 사용해 압력 강하, 조업압력, 점도 등이 막지지천을 통한 유체 흐름에 미치는 영향을 조사하였는데, 이 막지지천을 통한 유체 흐름은 Darcy's law를 만족시켰다.

GFRP복합재료의 피로거동은 하중형식, 재질 및 섬유의 강화구조, 환경적인 인자들의 영향을 크게 받는것으로 알려져 있다. 본 연구에서는GFRP의 피로거동에 미치는 증류수 흡습의 영향을 알아보기 위해 chopped strand glass mat강화 불포화 polyester수지 복합재료의피로특성을 조사하였다. 피로균열은 건조재와 흡습재 모두 피로 cycle초기에 발생하며 그 후 균열성장이 점차 둔화되는 영역과 가속되는 영역으로 나뉘어졌다. 또한 증류수의 흡습은 섬유와 기지재 사이의 결합력을 저하시키며 그로 인해 균영성장방향에 수직인곳에서의 fiber pull-out 발생과 균열성장방향에 있는 섬유들에서의 debonding이 증가하여 피로강도가 저하하였다.

This study was carried out to find out the effect of dietary intake on cognitive function retardation in old age using dietary survey and cognitive function test. The subjects were 332 men of 50-94 years old and their activities of daily living were very similar. The cognitive function was tested by Mini Mental State Examination (MMSE)-K which was translated from MMSE, and the 24-hour recall method was used for dietary survey. Scoring of MMSE-K was a little different from MMSE, that is, in case of no education, one to four points were added to exclude the effect of education which has been considered as a confounder by many researchers. The number of subjects belonging to below 23 of MMSE-K score was increased by increasing age. Even though points were added in case of no education, the ratio of below 23 MMSE-K score group was diminished by increasing education. Therefore, education seems not to be a confounder but a independent variable on cognitive function. Income, past occupation, family type, self-evaluated health status did not play any effect on cognitive function significantly. On the other hand, the correlation between each nutrients and the score of cognitive function test showed that the more consumption of vitamin A and protein, the higher cognitive function score was obtained. In case of iron and Ca, even though it was not statistically significant, there was a tendency of increasing cognitive function score by increasing the intake of those nutrients. This study suggests that micronutrient intakes might be more related to cognitive function than macronutrients.

To suggest the development possibility of immunostimulating materials from lactic acid bacteria (LAB) postbiotics, Lactobacillus sakei/Leuconostoc mesenteroides were isolated from Kimchi. Next, two isolated LAB were cultured to prepare postbiotics (LABP) to measure macrophage activity. LABP significantly increased the production of macrophage stimulating factors such as nitric oxide, tumor necrosis factor-α, and interleukin-6. LABP-crude polysaccharides (CP) fractionated from LABP by EtOH precipitation not only showed more potent macrophage stimulating activity but also induced phagocytic activity in a dose-dependent manner. In addition, LABP-CP was identified as polysaccharides with a major monosaccharide composition of mannose (59.1%), glucose (23.0%), and galactose (14.0%) with high-molecular-weight of 103.5~126.7 kDa. In conclusion, postbiotics prepared from LAB isolated from Kimchi were confirmed to have industrial applications as a functional material with immunostimulating activity.

Cyanobacteria have been used as pollution indicator species in freshwater ecosystems, and identifying their fluctuations can be an important part about management of surface waters globally. Cyanotoxins produced by cyanobacteria are directly or indirectly a threat to human and environmental health. In order to confirm the potential risk of these cyanotoxins, the fluctuations of phytoplankton and phylogenetic analysis of cyanotoxin synthetase genes were conducted at each point in the Yeongsan River water system in Gwangju from November 2021 to October 2022. Diatoms which grow well in winter were dominant at 99.4 ~ 99.5%, and diatoms and green algae were dominant from the spring to autumn when the water temperature rises. Stephanodiscus spp. were dominant at 92.7 to 97.5 % at all sites in the winter, and Aulacoseira spp., which grow in warm water temperatures, were dominant in summer and autumn. Microcystis aeruginosa was dominant at 25.2% in summer only at site 5. mcyB and anaC have been detected as cyanotoxin synthetase genes. The phylogenetic tree of anaC could be divided into two groups (Group 1 & Group 2). Group 1 contained Aphanizomenon sp. and Cuspidothrix issatschenkoi. It is combined with Aphanizomenon sp. and Cuspidothrix issatschenkoi, which are known to produce cyanotoxins.