Earticle

본 연구는 사회적 고립 수준에 따라 인지기능에 차이가 있는지, 그리고 사회적 고립을 구성하는 개별 항목이 인지기능 수준과 관련성이 있는지 분석하는 것이 목적이다. 본 연구는 사회적 고립을 배우자 혹은 자녀가 없는 구조적 고립상태와 가족, 친구, 공식적 사회단체 등과 접촉하지 않는 접촉 고립상태로 구분하였다 본 연구는 한국고령화연구패널 5차 자료 중 65세 이상 노인 3,971명을 대상으로 다변수 회귀분석을 실시하였다. 분석 결과에 의하면 사회적으로 고립되어 있을수록 인지기능 수준이 낮다는 점을 확인하였다. 사회적 고립의 여러 구성 요소 중 친구∙이웃 고립, 사회활동 고립이 인지기능과 관련성이 있다는 점도 확인하였다. 노인의 인지기능 약화를 방지하기 위해 다양한 사회활동 참여를 위한 정책이 필요한 것으로 판단된다. 사회적 고립의 영향을 고려할 때 향후 사회적 고립에 영향을 주는 요인을 분석하는 것도 필요하다.

The objective of the study was to analyze difference in cognitive function according to social isolation level in elderly Korean. The author classified the social isolation into the structural isolation and contact isolation. Structural isolation corresponded to the no spouse or no children and the contact isolation corresponded to the absence of contact with children, friends or social association. Author conducted multivariate regression analysis with the elderly people aged 65 years or older from the 5th wave of the Korean Longitudinal Study of Ageing data. Number of sample was 3,971. It was confirmed that the level of cognitive function was lower according to level of social isolation. It was also confirmed that friends/neighborhood isolation, and social activity isolation showed significant relationships with cognitive functions. Based on the results, author suggested that to protect the elderly from negative effects of social isolation, we needed the policy to promote elderly's the participation in social activity. The study to analyze the factors related to social isolation was also needed.

Among 116 bacterial strains isolated from Korean fermented foods, one strain (SS-76) was selected for producing new oligosaccharides in a basal medium containing maltose as the sole source of carbon. Upon morphological characterization using scanning electron microscopy, the cells of strain SS-76 appeared rod-shaped; subsequent 16S rRNA gene sequence analysis revealed that strain SS-76 was phylogenetically close to Bacillus subtilis. The main oligosaccharide fraction B extracted from the culture supernatant of B. subtilis SS-76 was purified by high performance liquid chromatography. Subsequent structural analysis revealed that this oligosaccharide consisted only of glucose, and methylation analysis indicated similar proportions of glucopyranosides in the 6-linkage, 4-linkage, and non-reducing terminal positions. Matrix-assisted laser-induced/ionization time-of-flight/mass spectrometry and electrospray ionization-based liquid chromatography-mass spectrometry/mass spectrometry analyses suggested that this oligosaccharide consisted of a trisaccharide unit with 1,6- and 1,4-glycosidic linkages. The anomeric signals in the $^1H$-nuclear magnetic resonance spectrum corresponded to ${\alpha}$-anomeric configurations, and the trisaccharide was finally identified as panose (${\alpha}$-D-glucopyranosyl-1,6-${\alpha}$-D-glucopyranosyl-1,4-D-glucose). These results suggest that B. subtilis SS-76 converts maltose into panose; strain SS-76 may thus find industrial application in the production of panose.

In this paper, we designed and made isolation device and experimental structure through envelope design method base on energy balance theory and performed shaking table test to identify the dynamic response characteristics. The main parameters of this study were stiffness and yield strength of U-shaped steel damper and we analyzed acceleration, displacement, and internal force of isolation system in accordance with the main parameters. According to the increase of stiffness and yield strength of steel damper, there were growing tendency in response of upper structure. Based on this study, it is necessary for us to perform quantitative evaluation of isolation system through additional dynamic response analysis.

배경: 야생 망초(줄기와 잎)의 성분을 분석한 결과에서 생리활성 성분의 함유가 확인되어 화합물의 규명이 필요 하다. 목적: 망초에는 항산화성 물질이 함유되었다는 선행연구 결과가 있어서 화합물의 분자적 구조를 연구하는 것이 목적이었다. 방법: 망초(줄기와 잎) 초음파 분쇄물을 1차로 90% 메탄올로, 다음에 유기 용매로 추출하였다. 다음에 HPLC, LC/MS 크로마토그래피 등으로 분획하였고, 분핵물을 NMR 분광기로 정밀 분석하여 분자의 구조를 동정하였 다. 결과: 망초 100 g을 초음파기로 파쇄하여 90% methanol로 추출하고, 감압 농축하여 조 추출물 11.96 g을 얻었다. 조추출물을 유기용매로 재추출하여 n-hexane으로 123.8 mg, dichloromethane으로 448.2 mg, ethyl acetate(EA)로는 1047.7 mg, butanol로는 2563.8 mg, water로는 7.04 g을 얻었다. EA 추출물을 LC-MS 크로마토그래피로 분획하고, 정 밀 분획하여 F1~F20의 20개를 얻었다. F15 분획을 다시 분획하여 9개를 얻었다. F17 분획을 재분획하여 10개의 분획 을 얻었다. F15-7 분획물을 LC-MS 분석과 NMR 분광기로 분석한 결과는 이 화합물의 구조가 3,5-di-caffeoylquinic acid로 확인되었다. F17-4와 F17-5의 구조를 조사한 결과는 Quercetin-3-o-β-galactose로 동정 되었다. F17-10의 구조 를 확인한 결과는 1,3,4-tri-caffeoylquinic acid로 확인되었다. 결론: 본 연구에서 망초 성분에도 항산화성 물질이 있었 으며, 이의 활용성을 기대하며, 식물에는 항산화성 물질인 phenol 성분을 다양하게 함유하였다.

Background: As a result of analyzing the components of wild Conyza canadensis, it contains physiologically active ingredients, so it is necessary to identify the compound. Purposes: It was to study the compound's molecular structure; a previous study showed that C. canadensis contains antioxidant substances. Methods: The ultrasonic pulverized lysate of C. canadensis stem and leaves was first extracted with 90% methanol and then five organic solvents. Next, the extracts was fractionated by HPLC, LC/MS chromatography, and NMR analyzers identified the molecular structure. Results: 100 g of dry C. canadensis was sonicated in 90% methanol and concentrated under reduced pressure to 11.96 g of a crude extract. Then, this crude was extracted with five types of solvents to obtain 123.8 mg of n-hexane, 448.2 mg of dichloromethane, 1047.7 mg of ethyl acetate (EA), 2563.8 mg of butanol, and 7.04 g of water. The EA extracts were fractionated by LC-MS and then re-fractionated to obtain F1 to F20. Next, the F15 was further fractionated to obtain nine fine fractions. Finally, the F17 fraction was re-fractionated to obtain ten fine fractions. As a result of LC-MS and NMR spectrometer analysis of the F15-7, the structure of this compound was confirmed as 3,5-di-caffeoylquinic acid. As a result of examining the structures of the F17-4 and F17-5 fractions, Quercetin-3-o-β-galactose was identified. In addition, the form of the F17-10 was confirmed to be 1,3,4-tri-caffeoylquinic acid. Conclusions: This study demonstrated that C. canadensis contained phenolic antioxidants, and its utilization may be expected.

This study is about the design of an elastic support system to isolate the structural noise of the low accumulator of the naval artillery among the equipment mounted on a warship. As the structural noise measurement value of the low accumulator transmitted to the ship exceeded the standard value, a method of applying an elastic mount between the equipment and the ship was devised to isolate the structural noise. By calculating the target vibration isolation efficiency, the vibration isolating system was designed in consideration of design factors such as the system's natural frequency and static displacement. Finally, the performance of the structural noise reduction of the designed vibration isolating system was verified by evaluating the structural noise transmitted to the foundation plate of the equipment from the low accumulator to which designed elastic support system was applied.

[목적] 본 연구는 중장년층의 골프 커뮤니티 활동이 사회적 고립감과 삶의 의미에 미치는 구조적 관계를 규명하고, 사회적 연결감의 매개효과를 검증하는 데 목적이 있다. [방법] 수도권 지역의 40~64세 골프 커뮤니티 참여자 378명을 대상으로 설문조사를 실시하였으며, SPSS 29.0과 AMOS 29.0을 활용하여 확인적 요인분석, 구조방정식모형 분석 및 부트스트래핑을 실시하였다. [결과] 골프 커뮤니티 활동은 사회적 연결감과 삶의 의미에 유의한 정적 영향을, 사회적 고립감에는 유의한 부적 영향을 미쳤다. 또한 사회적 연결감은 사회적 고립감에 유의한 부적 영향을, 삶의 의미에는 유의한 정적 영향을 미쳤으며, 골프 커뮤니티 활동과 사회적 고립감 및 삶의 의미 간의 관계에서 각각 유의한 부분매개효과를 나타냈다. [결론] 골프 커뮤니티 활동은 중장년층의 사회적 연결을 강화하여 사회적 고립감을 완화하고 삶의 의미를 증진하며, 사회·심리적 건강을 위한 커뮤니티 기반 골프 활동의 중요성을 시사한다.

[Purpose] This study examined the structural relationships of golf community participation with social isolation and meaning in life among middle-aged and older adults and the mediating effect of social connectedness. [Method] A survey of 378 golf community participants aged 40–64 years in the Seoul metropolitan area was analyzed using SPSS 29.0 and AMOS 29.0 through confirmatory factor analysis, structural equation modeling, and bootstrapping. [Result] Golf community participation positively affected social connectedness and meaning in life and negatively affected social isolation. Social connectedness reduced social isolation and enhanced meaning in life, partially mediating the effects of golf community participation on both outcomes. [Conclusion] Golf community participation may reduce social isolation and enhance meaning in life by strengthening social connectedness, highlighting the importance of community-based golf activities for middle-aged and older adults' social and psychological well-being.

In this study, the structural analysis for bellows joint of high-performance that can enhance the performance of seismic isolation piping was performed. Bellows joint is that the corrugated flexible piping is connected at the both sides of elbow. An one axis of the bellows joint fixed, and the other end of the axis changes the position from 0° to 315° for the radius displacement of 500 mm. Results obtained are as follows for this case in analysing of the maximum stress and plastic strain of the bellows joint. As the location of the base isolation displacement get farther from the fixed pipe, the bellows joint is pulled, and the maximum stress and plastic deformation is increased. And so the maximum stress occurs near the bellows at both ends of the elbow. Displacement in the 135° position, a maximum stress of 837 MPa and a plastic strain of 3.00% was the highest.

Sixteen antioxidative active compounds isolated from the EtOAc layer of MeOH extracts of kochujang, Koreanfermented red pepper paste, were structurally elucidated as fumaric acid, methyl succinate, succinic acid furan-2-yl estermethyl ester (gochujangate, a novel compound), 2-hydroxy-3-phenylpropanoic acid, 3,4-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 6,7-dihydroxy-2H-chromen-2-one (esculetin), caffeic acid, cis-p-coumaricacid, trans-p-coumaric acid, daidzin, genistin, apigenin 7-O-β-D-apiofuranosyl(1→2)-β-D-glucopyranoside, apigenin 7-O-β-D-glucopyranoside, and quercetin 3-O-α-L-rhamnopyranoside by mass spectrometry (MS) and nuclear magnetic resonance(NMR) experiments. These compounds were analyzed for the first time as antioxidants from kochujang.

Aldose reductase catalyzes the conversion of glucose into sorbitol. Inhibiting this enzyme in diabetes mellitus can delay or prevent pathogenic process. Aldose reductase inhibitor was screened from Korean fermented soybean pastes (Doen-jang) and purified via sequential processes of ethanol extraction, HP-20 column chromatography, ethyl acetate extraction, silica gel column chromatography, and crystallization. Aldose reductase inhibitor was identified as genistein with molecular weight of 270 Da and molecular formula of C15H10O5 based on UV spectrometry, 1H and 13C NMR3, and mass spectrometry. Genistein inhibited aldose reductase of pig lens with IC50 level of 20 uM. Because genistein was effective against aldose reductase of animal source, it may be a potential therapeutic agent for diabetic complications.

이 연구는 기독교인과 비기독교인 간 다문화가정 어머니의 신앙, 자아존중감, 결혼적응, 양육태도와 아동의 정서적 고립감 및 학교부적응 간의 구조적 관계를 검증하고자 하였다. 결론은 1. 다문화가정 어머니의 기독교신앙은 자아존중감, 결혼적응, 양육태도에 통계적으로 유의미한 영향력을 갖지 못하는 것으로 확인되었다. 2. 어머니의 기독교신앙은 아동의 정서적 고립감과 학교부적응에 유의미한 영향력을 갖지 못하는 것으로 확인되었다. 3. 어머니의 자아존중감, 결혼적응, 양육태도는 아동의 정서적 고립감의 관계에서 통계적으로 유의미한 차이가 없는 것으로 나타났다. 4. 어머니의 자아존중감, 결혼적응, 양육태도가 아동의 학교부적응에 영향에서는 통계적으로 유의미한 차이가 있는 것으로 나타났다. 5. 어머니의 자아존중감, 결혼적응, 양육태도가 아동의 정서적 고립감을 매개변인으로 하여 아동의 학교부적응에 대한 검증결과 어머니의 부정적인 양육태도가 높을수록 아동의 정서적 고립감과 학교부적응이 높아지는 것으로 나타났다.

This research is to clarify the structural relationships of mothers' faith, their self-esteem, matrimonial adjustment, bringing attitude, and their child's emotional isolation. Also, this research emphasizes the school maladjustment of multi-cultural family between Christian and non-Christian. A group of 700 elementary school students and their mothers of multi-cultural family was selected from South Korea. To analyze the data, SPSS 19 was used to find t-test and multiple regression analysis, and AMOS was used for path analysis among variables. The result of this research is as follows: 1) there is no significant effect between mothers' self-esteem, matrimonial adjustment, bringing attitude of multi-cultural family, and their child's emotional isolation. 2) there is no significant effect between mothers' Christian faith, their child's emotional isolation, and school maladjustment. 3) there is no significant effect between mothers' self-esteem, matrimonial adjustment, bringing attitude and their child's emotional isolation. 4) there is a statistical significant difference between mothers' self-esteem, matrimonial adjustment, bringing attitude of multi-cultural family, and their child's school maladjustment. 5) there is a partial significant difference between a mother's self-esteem, matrimonial adjustment, bringing attitude, and their child's emotional isolation caused by meditation variances. In other words, mothers' negative bringing attitude have a negative influence on their child's emotional isolation, and school maladjustment.

Ten steroidal compounds as impurities in canrenone were isolated from the enriched mother liquor by using various chromatographic methods. Their structures were elucidated by spectrometric analysis, among which three new compounds were characterized as 3-(3-oxo-7$\alpha$-(ethoxycarbonyl)methyl-17$\beta$-hydroxy-4-androsten-17$\alpha$-yl) propionic acid $\gamma$-lactone (1), 3-(3-oxo-7$\alpha$-ethoxy-17$\beta$-hydroxy-4-androsten-17$\alpha$-yl) propionic acid $\gamma$-lactone (2) and 3-(3-oxo- 5$\beta$-propionic acid-$\gamma$-lactone-6$\beta$,17$\beta$-hydroxy-4-androstan-17$\alpha$-yl) propionic acid $\gamma$-lactone (3).

The fruits of Morinda citrifolia, Linn. afforded a new constituent, morinaphthalenone (1), and three known constituents, scopoletin (2), 1, 3-dimethoxy-anthraquinone (3) and 1, 2-dihydroxy-anthraquinone (4). The structures of these isolated compounds were determined by spectroscopic methods, including 1D- and 2D-NMR (COSY-45, HMQC, HMBC) techniques, as well as by comparison with published values.

Squalene synthase plays an important role in the cholesterol biosynthetic pathway. Inhibiting this enzyme in hypercholesterolemia can lower not only plasma cholesterol but also plasma triglyceride levels. A squalene synthase inhibitor was screened from Prunus mume fruit, and then purified via sequential processes of ethanol extraction, HP-20 column chromatography, ethyl acetate extraction, silica gel column chromatography, and crystallization. The squalene synthase inhibitor was identified as chlorogenic acid with a molecular mass of 354 Da and a molecular formula of $C_{16}H_{18}O_9$ based on UV spectrophotometry, $^1H$ and $^{13}C$ NMRs, and mass spectrometry. Chlorogenic acid inhibited the squalene synthase of pig liver with an $IC_{50}$ level of 100 nM. Since chlorogenic acid was an effective inhibitor against the squalene synthase of an animal source, it may be a potential therapeutic agent for hypercholesterolemia.

Three new compounds were isolated from the methanol extracts of buckwheat (Fagopyrum esculentum) hull, and their structures were determined to be 6,7-dihydroxy-3,7-dimethyl-octa-2(Z),4(E)-dienoic acid (1), 6,7-dihydroxy-3,7-dimethyl-octa-2(E),4(E)-dienoic acid (2), and 4,7-dihydroxy-3,7-dimethyl-octa-2(E),5(E)-dienoic acid (3) by NMR and MS spectroscopic analyses. These compounds at $500{\mu}g$ concentration showed antimicrobial activity against Staphylococcus aureus, demonstrated by the paper disc method.

Compounds of (+)-5,5'-dimethoxylariciresinol (1) and (3S,5R,6S,7E)-5,6-epoxy-3-hydroxy-7-megastigmen-9-one (2) were isolated from an EtOAc extract of the whole plant of Sasa borealis (Hack.) Makino (Gramineae) for the first time in the present investigation. The structures of compounds were identified by analysis of spectral data including 1D- and 2D-NMR spectra as well as by comparison of their data with the published values. These compounds have never been isolated previously from the family Gramineae.

Trichoderma strain T-33 has been demonstrated to have inhibitory effect on the fungus species Cytospora chrysosperma. Here, an active antifungal compound was obtained from Trichoderma strain T-33 extract via combined separation technologies, including organic solvent extraction, liquid chromatography, and thin-layer chromatography. The purified compound was further characterized by advanced analytical technologies to elucidate its chemical structure. Results indicated that the active antifungal compound in Trichoderma strain T-33 extract is 2,5-cyclohexadiene-1,4-dione-2,6-bis (1,1-dimethylethyl).

Fuzzy control is a practical alternative for a variety of challenging control applications since it provides a convenient method for constructing nonlinear controllers via the use of heuristic information. This approach provides a formal methodology for representing, manipulating, and implementing a human's heuristic knowledge about how to modeled and to control a system. This paper focuses on the application of fuzzy control approach to the surge phenomena in centrifugal compression system. Fuzzy controller is designed to consist of an active surge control and phase control without any explicit system models, but driven in the human thinking mechanism. This fuzzy control methodology suggested in this work reproduced well the main characteristics of the turbo compressor dynamic model developed by Moore and Gretzer and give place to a more precise and easy to handle representation. Application and simulation results are performed to demonstrate the effectiveness of this controller. Studies show that, the proposed controller provides good tracking control performance for the compression system at different operating conditions and moreover improves the dynamic performances of the system.

Semi-active isolation systems based on leverage-type stiffness control strategies have been widely studied. The main concept behind this type of system is to adjust the stiffness in the isolator to match the fundamental period of the isolated system by using a simple leverage mechanism. Although this system achieves high performance under far-field earthquakes, it is unsuitable for near-fault strong ground motion. To overcome this problem, this study considers the potential energy effect in the control law of the semi-active isolation system. The minimal energy weighting (MEW) between the potential energy and kinetic energy was first optimized through a series of numerical simulations. Two MEW algorithms, namely generic and near-fault MEW control, were then developed to efficiently reduce the structural displacement responses. To demonstrate the performance of the proposed method, a two-degree-of-freedom structure was employed as a benchmark. Numerical results indicate that the dynamic response of the structure can be effectively dampened by the proposed MEW control under both far-field and near-fault earthquakes, whereas the structural responses resulting from conventional control methods may be greater than those for the purely passive control method. Moreover, according to experimental verifications, both the generic and near-fault MEW control modes yielded promising results under impulse-like earthquakes. The practicability of the proposed control algorithm was verified.