• BMB Reports
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• 제44권5호
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• pp.298-305
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• 2011

Most intracellular reactive oxygen species (ROS), especially superoxide anion ($O_2^{{\bullet}_-}$) that is converted from oxygen, are overproduced by excessive electron leakage from the mitochondrial respiratory chain. Intracellular oxidative stress that damages cellular components can contribute to lifestyle-related diseases such as diabetes and arteriosclerosis, and age-related diseases such as cancer and neuronal degenerative diseases. We have previously demonstrated that the excessive mitochondrial $O_2^{{\bullet}_-}$ production caused by SDHC mutations (G71E in C. elegans, I71E in Drosophila and V69E in mouse) results in premature death in C. elegans and Drosophila, cancer in mouse embryonic fibroblast cells and infertility in transgenic mice. SDHC is a subunit of mitochondrial complex II. In humans, it has been reported that mutations in SDHB, SDHC or SDHD often result in inherited head and neck paragangliomas (PGLs). Recently, we established Tet-mev-1 conditional transgenic mice using our uniquely developed Tet-On/Off system, which equilibrates transgene expression to endogenous levels. These mice experienced mitochondrial respiratory chain dysfunction that resulted in $O_2^{{\bullet}_-}$ overproduction. The mitochondrial oxidative stress caused excessive apoptosis leading to low birth weight and growth retardation in the neonatal developmental phase in Tet-mev-1 mice. Here, we briefly describe the relationships between mitochondrial $O_2^{{\bullet}_-}$ and aging phenomena in mev-1 animal models

• Journal of Nutrition and Health
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• 제16권1호
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• pp.10-20
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• 1983

In order to establish tissue lipid status in animal on feeding of various dietary fat and oils, each group of rats was fed a semisynthetic diet containing 10%(w/w) mackerel oil (MO), eel oil (EO), soybean oil (SO), rapeseed oil (RO) or beef tallow (BT) for 1, 2 and 4 weeks, After each feeding period, levels of cholesterol, triglyceride and phospholipid were measured in serum. Fatty acid ${\leftarrow}$ composition was also investigated in serum and tissue lipids. Levels of total serum cholesterol were lower but HDL-cholesterol were higher in fish oil groups, which resulted in significantly higher ratio of HDL to total cholesterol in the fish oil groups. Fish oil groups, in general, also had lower levels of serum triglyceride and phospholipid than other groups, but S0 group maintained as low phospholipid levrl as fish oil groups. Fatty acid composition of dietary fat was reflected in all the tissues investigated but with varying degrees. Very long chain fatty acids, specific components exclusively found in fish oils were most well reflected in liver and relatively well in serum, whereas linoleic acid and erucic acid of SO and RO in the diet were better shown up in heart and adipose tissue. It attracted a particular attention that major proportions of long chain monoenoic acids $(C_{22:1})$ occurring both in MO and RO were detected separately in liver and heart plus adipose tissue, the result of which strongly indicates that there is a significant difference in metabolism between isomers $(C_{22:1}\;w\;11\;and\;C_{22:1}\;w\;9,\;respectively)$. It is suggested from this study that differences in lipid status as well as in the levels of serum lipids result from uniqueness in metabolism of each different fatty acid and give rise to distinguishable change in serum lipoprotein pattern, followed by diet with different fat sources.

• Journal of Biosystems Engineering
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• 제36권1호
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• pp.9-14
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• 2011

This study was carried out to develop a vine crusher for harvesting sweet potato. The experimental two-row vine crusher attachable to agricultural tractor composed of vine crushing part with frail type vine crushing blades and vine lifting blades, power transmission part with chain and gear transmission mechanism, crushing height control part with two control wheels and manual levers, and implement frames, was designed and fabricated. And this vine crushing performance was also analyzed. From vine crushing tests, backward travel direction (i.e., rotational direction of the vine crushing blades) showed better vine crushing performance than forward travel direction. Crushing ratio of remained vine was increased, and length of remained vine and length of crushed vine were decreased as working speed was decreased and rotational speed of vine crushing blades was increased. At a working speed of 0.27 m/s and rotational speed of vine crushing blades of 800 rpm, crushing ratio of remained vine was 98%, length of remained vine was 104 mm, and length of crushed vine was 327 mm. But, when crushing vine on irregular ridges, vines and mulching vinyl were wound in the vine crushing part. Therefore, change of location of power transmission chain mechanism, and an automatic control device for controlling crushing height were needed.

• Molecules and Cells
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• 제37권8호
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• pp.598-604
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• 2014

Fatty acids, important components of a normal diet, have been reported to play a role in bone metabolism. Osteoclasts are bone-resorbing cells that are responsible for many bone-destructive diseases such as osteoporosis. In this study, we investigated the impact of a medium-chain fatty acid, capric acid, on the osteoclast differentiation, function, and survival induced by receptor activator of NF-${\kappa}B$ ligand (RANKL) and macrophage colony-stimulating factor (M-CSF). Capric acid inhibited RANKL-mediated osteoclastogenesis in bone marrow-derived macrophages and suppressed RANKL-induced $I{\kappa}B{\alpha}$ phosphorylation, p65 nuclear translocation, and NF-${\kappa}B$ transcriptional activity. Capric acid further blocked the RANKL-stimulated activation of ERK without affecting JNK or p38. The induction of NFATc1 in response to RANKL was also attenuated by capric acid. In addition, capric acid abrogated M-CSF and RANKL-mediated cytoskeleton reorganization, which is crucial for the efficient bone resorption of osteoclasts. Capric acid also increased apoptosis in mature osteoclasts through the induction of Bim expression and the suppression of ERK activation by M-CSF. Together, our results reveal that capric acid has inhibitory effects on osteoclast development. We therefore suggest that capric acid may have potential therapeutic implications for the treatment of bone resorption-associated disorders.

• 미생물학회지
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• 제31권4호
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• pp.261-266
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• 1993

유일한 탄소 및 에어지원으로 메탄올만을 이용하여 성장하는 새로운 절대 메탄올 자화세균을 토양으로 부터 분리하였다. 분리균주는 그람음성의 운동성이 없고 포자를 형성하지 않는 간균으로 정대호기성 세균이었다. 이 균주는 catalase 활성과 oxidase 활성을 가지고 있으며, nitrate를 nitrite로 환원시킬 수 있고 성장시 vitamin이나 특이한 생육인자를 요구하지 않았다. 세대시간은 1.6시간으로 메탄올 동화경로로는 ribulose monophosphate pathway(Entner-Doudoroff 변형경로)를 이용하나 α-ketoglutarate dehydrogenase 활성은 없었다. Ammonium ion은 glutamate dehydrogenase를 이용하여 동화하였다. DNA의 guanine plus cytosine 함량은 61.0 mol%이고 세포내 지방산으로는 누고 straight-chain saturated C$^{16:0}$ acids(palmitie acids)와 unsaturated C$^{16:1}$ acids(palmitoleic acids)를 가지고 있으나 이외에도 두 종류의 unidentified C$_{17}$ branched fatty acid도 포함하고 있었다. Major ubiquinone은 Q-8이나 Q-6와 Q-7을 특이하게 소량 가지고 있었다. Phospatidylethanolamine과 Phosphatidylglycerol이 주요한 phospholip의 구성물질이나 diphosphatidylgycerol도 소량 포함하고 있었다. 위와같은 생리적, 생화학적 자료로 부터 분리균주를 새로은 종 즉, Methylohacillus methanolovorus sp. nov.로 명명하였다.

• 접착 및 계면
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• 제12권4호
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• pp.105-110
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• 2011

폴리에스터/멜라민 경화형 도료는 기계적 물성, 내화학성 및 내마모성 등이 우수하여 pre-primed 도료 및 pre-coated metal에 널리 사용되고 있다. 그러나, 폴리에스터 수지 도료의 경화 도막은 강인하지만 유연성과 성형성이 낮은 문제점을 갖고 있다. 본 연구에서는 polycarbonate diol의 long alkyl chain을 폴리에스터 분자 구조 내에 연결시켜 경화 도막의 성형성을 개선하고자 하였으며, 성형성이 개선된 폴리에스터 도료의 선도장 강판용 도료의 적용 가능성을 확인하였다. 또한, 폴리카보네이트디올 분자량이 경화 도막 물성에 미치는 영향을 평가하고자 인장강도와 점탄성을 측정하였으며, 성형성을 확인하고자 drawing test를 실시하였다.

• 한국건설관리학회논문집
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• 제15권4호
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• pp.20-29
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• 2014

건설 프로젝트가 대형화, 복잡화됨에 따라 건설 프로젝트에 투입되는 자재의 효과적 관리를 위하여, 바코드, RFID 등의 다양한 인식 기술의 적용이 시도되고 있다. 하지만 기존의 바코드, RFID 등의 기술의 적용은 기존 관리 업무에서 사용되지 않던 RFID 장비의 추가 투입과 부재 관리를 위한 RFID tag 부착 등의 추가 작업이 요구됨으로써, 공장 및 현장의 작업자들에게 관리 비용 증가, 추가 작업의 번거로움 등의 문제를 발생시키는 한계를 가지고 있었다. 또한 해당 장치를 인식하기 위한 별도의 RFID 리더를 소지하지 않는 경우, 해당 부재를 작업자가 해당 부재의 정보를 인식하기 어려운 한계를 가지고 있다. 따라서 본 연구에서는 Long-lead item 자재 중 철골과 PC 부재를 대상으로, 앞 서 제기된 문제점 개선을 위해 스마트 폰 등의 영상처리 기능을 이용한 문자인식 기술을 대체 기술로 제안하고, 제안된 문자인식 기술의 적용 가능성 테스트를 통해 기술의 적용가능성을 제시하였다. 또한 제안된 문자인식 기술을 보다 효과적으로 적용하기 위한 문자 표기 방식, 코드 체계를 제안하고, 기존 RFID 기반 물류 관리 프로세스와 비교를 통해 문자인식 기술이 실제 적용될 경우의 효과를 제시하였다.

• 한국균학회지
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• 제29권2호
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• pp.104-109
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• 2001

Polyphosphate의 Candida albicans와 Trichophyton mentagrophytes에 대한 항진균 작용에 대하여 연구하였다. 평균 사슬길이가 15, 45, 75인 polyphosphate는 진균에 대하여 성장억제 효과를 나타낸 반면, pyrophosphate는 성장억제 효과가 없었다. 사슬길이가 증가함에 따라서 진균 성장억제 효과가 증가하는 것으로 관찰되었으며 $800\;{\mu}g/ml$ 농도에서는 균주의 성장을 완전히 억제시켰다. $Mg^{2+}$나 $Ca^{2+}$의 첨가는 polyphosphate의 성장억제 효과를 감소시켰다. Polyphosphate를 처리한 C. albicans에서는 핵산물질의 유리가 관찰되었으며, 세포 swelling이나 표면돌출과 같은 세포형태 변화도 관찰되었다. 세포막 불투과성 물질인 propidium iodide는 Polyphosphate를 처리한 C. albicans의 핵을 염색하는 것이 관찰되었다. Polyphosphate의 항진균 작용은 polyphosphate가 진균 세포벽이나 세포막의 필수 양이온에 대한 chelation 효과에 의한 것으로 사려된다.

• 한국정보과학회논문지:소프트웨어및응용
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• 제26권11호
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• pp.1298-1305
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• 1999

네트워크 및 분산 처리 기술의 발달로 분산 환경에서 동작하는 응용 프로그램에 대한 생산성 향상이 요구되고 있다. 본 논문에서는 MVC(Model, View, Controller) 패턴을 기반으로 하는 분산 응용 프로그램의 생산성 향상을 위해, 조립식 분산 응용의 작성을 지원하는 분산 객체 조립기, DOC(Distributed Object Composer)를 소개한다. 분산 객체 조립성의 기반이 되는 DOC의 구성적{{) '전체'를 창조해 내기 위해 여러 요소들을 결합, 배치하여 하나의 예술작품을 성립시키는 방법. 모아서 조립한다는 의미.}} 인터페이스(Structural Interface)는 기존 객체지향 기술의 절차적 인터페이스(Procedural Interface)에 비해 콤포넌트 재사용성을 개선하고, 분산 응용의 신속한 개발을 지원하여, 소프트웨어의 생산성 및 확장성을 향상시킨다. 또한, DOC 방식으로 모델링하고 구현한 공급망 관리(Supply Chain Management: SCM) 응용 프로그램의 조립식 작성을 통해, DOC의 실시간 정보 처리 및 조립 기능을 보인다.DOC는 이질적인 통신 환경에서 클라이언트와 서버 객체간의 네트워크 투과성을 제공하는 미들웨어, CORBA를 기반으로 한다. 또한, 분산 객체들 간의 상호작용을 자동 처리하기 위해 Java의 관찰자/피관찰자(Observer/Observable)를 확장한 분산 관찰자/피관찰자 패턴을 정의하여 DOC와, 서버 및 클라이언트의 분산 응용 객체들을 정의하기 위한 인터페이스에 적용한다.Abstract Due to the availability of advances in network and distributed processing technologies, the enhanced productivity of application software that runs on distributed environment is demanded. In this paper, we introduce the Distributed Object Composer (DOC) that supports the structural composition of distributed applications for the enhanced productivity of MVC (Model, View, Controller) pattern-based application programs. The structural interface of DOC that is the basis for the composibility of distributed objects increases the reusability of software components and provides better software productivity and extendibility than the procedural interface of the traditional object-oriented technology by supporting rapid constructions of distributed applications. In this paper, we also discuss the real-time information processing and composibility features of DOC by applying the DOC mechanism to the Supply Chain Management (SCM) application.DOC is implemented using the CORBA middleware that supports the network transparency between client and server objects on heterogeneous communication environments. We apply the distributed Observer/Observable pattern that extends the Observer/Obseverable of Java to DOC itself and distributed client/server objects as their interface definitions for the automatic interactions of distributed objects.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권8호
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• pp.2900-2922
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• 2021

In this paper, the power spectral density(PSD) for Multilevel Minimum Shift Keyed signal with modulation index h = 1/2 (M-ary MSK) are derived using the mathematical method of the Markov Chain model. At first, according to an essential requirement of the phase continuity characteristics of MSK signals, a complete model of the whole process of signal generation is built. Then, the derivations for autocorrelation functions are carried out precisely. After that, we verified the correctness and accuracy of the theoretical derivation by comparing the derived results with numerical simulations using MATLAB. We also divided the spectrum into four components according to the derivation. By analyzing these figures in the graphic, each component determines the characteristics of the spectrum. It is vital for enhanced spectral characteristics. To more visually represent the energy concentration of the main flap and the roll-down speed of the side flap, the specific out-of-band power of M-ary MSK is given. OMLCD(Optimum Maximum Likelihood Coherent Detection) of M-ary MSK is adopted to compare the signal received with prepared in advance in a code element T to go for the best. And M-ary MSK BER(Bit Error Rate) is compared with the same ary PSK (Phase Shift Keying) with M=2,4,6,8. The results show the detection method could improve performance by increasing the length of L(memory inherent) in the phase continuity.