• Journal of Ginseng Research
• /
• 제44권2호
• /
• pp.341-349
• /
• 2020

Background: The replicative senescence of human dermal fibroblasts (HDFs) is accompanied by growth arrest. In our previous study, the treatment of senescent HDFs with Rg3(S) lowered the intrinsic reactive oxygen species (ROS) levels and reversed cellular senescence by inducing peroxiredoxin-3, an antioxidant enzyme. However, the signaling pathways involved in Rg3(S)-induced senescence reversal in HDFs and the relatedness of the stereoisomer Rg3(R) in corresponding signaling pathways are not known yet. Methods: We performed senescence-associated β-galactosidase and cell cycle assays in Rg3(S)-treated senescent HDFs. The levels of ROS, adenosine triphosphate (ATP), and cyclic adenosine monophosphate (cAMP) as well as the mitochondrial DNA copy number, nicotinamide adenine dinucleotide (NAD)⁺/1,4-dihydronicotinamide adenine dinucleotide (NADH) ratio, and NAD-dependent sirtuins expression were measured and compared among young, old, and Rg3(S)-pretreated old HDFs. Major signaling pathways of phosphatidylinositol 3-kinase/Akt, 5' adenosine monophosphate-activated protein kinase (AMPK), and sirtuin 1/3, including cell cycle regulatory proteins, were examined by immunoblot analysis. Results: Ginsenoside Rg3(S) reversed the replicative senescence of HDFs by restoring the ATP level and NAD⁺/NADH ratio in downregulated senescent HDFs. Rg3(S) recovered directly the cellular levels of ROS and the NAD⁺/NADH ratio in young HDFs inactivated by rotenone. Rg3(S) mainly downregulated phosphatidylinositol 3-kinase/Akt through the inhibition of mTOR by cell cycle regulators like p53/p21 in senescent HDFs, whereas Rg3(R) did not alter the corresponding signaling pathways. Rg3(S)-activated sirtuin 3/PGC1α to stimulate mitochondrial biogenesis. Conclusion: Cellular molecular analysis suggests that Rg3(S) specifically reverses the replicative senescence of HDFs by modulating Akt-mTOR-sirtuin signaling to promote the biogenesis of mitochondria.

• 한국미생물·생명공학회지
• /
• 제43권3호
• /
• pp.177-186
• /
• 2015

국내 식품공전에 기술되어 시행중인 식품 내 벤조피렌 분석법은 회수율, 검출 및 정량 한계, 효용성과 정확성 등이 검증되어 적용되고 있다. 그러나, 기존의 시험법에는 시료의 추출 및 분리, 정제 등의 복잡한 전처리 과정이 포함되어 있다. 환경 및 식품 내 위해물질 검출법의 연구 및 개발의 현 추세는 시험비용과 시간소모를 최소화하고 시험과정을 단순화할 수 있는 비표지, 비파괴 분석법을 통해 관리 현장에서의 신속대응을 지향하고 있다. 본 총설에서는 현행의 벤조피렌 분석법에 대해 정리하고, 그 한계점을 극복하기 위한 새로운 시도로 라만 분광법을 이용한 벤조피렌 검출법에 대해 소개하고자 한다.

• 분석과학
• /
• 제18권5호
• /
• pp.425-430
• /
• 2005

본 연구에서는 대기 중 암모니아 성분의 농도 계측에 활용하는 간이비색계의 성능을 UV/VIS 분광계에 대비하는 방식으로 평가하였다. 본 연구의 목적상 두 가지 분석 시스템을 이용하여 검출한계, 재현성, 직선성, 정확도 등의 기준항목을 다양하게 비교하였다. 본 연구에 의하면, 간이비색계의 성능은 대체로 UV/VIS 분광계와 양호한 일치도를 보일 정도로 좋은 결과를 보였다. 검출한계를 평가한 결과 두 가지 시스템 모두 $3{\mu}g$에 가깝게 나타났다. 그러나 간이비색계의 경우, 아주 낮은 농도와 고농도대에서 상대적으로 문제점이 존재하는 것으로 나타났다. 예를 들어, 암모니아의 절대량이 $10{\mu}g$ 이하일 때는 재현성에 대한 문제가 두드러졌고, $100{\mu}g$ 이상의 고농도대에서는 직선성이 제한되는 문제로 인해 분석이 어려웠다. 따라서 만약 대기시료를 30 리터 정도로 채취한다고 가정하면, (별다른 희석을 가하지 않고 분석한다면) 500 ppb에서 5 ppm의 농도대에서 간이비색계를 적용하는 것이 유효한 것으로 나타났다. 농도대에 따른 간이비색계의 제한적인 특성을 충분히 감안하고 사용할 경우, 간이비색계를 활용한 분석은 상당히 양호한 결과를 생산하는 것이 가능하다는 결론을 내릴 수 있다.

• 분석과학
• /
• 제7권4호
• /
• pp.435-440
• /
• 1994

모세관 전기영동 장치를 이용하여 금속 표면 세척제(상품명 BFA와 BCA) 2종에 포함된 음이온 계면활성제에 대한 정성 및 정량분석을 수행하였다. Acetonitrile과 sodium benzoate를 포함하는 pH 10의 완충용액을 이용하여 18kV의 전압하에서 분리한 결과 $10^4$ 이상의 이론단수를 보이는 좋은 electropherogram을 얻을 수 있었다. S/N~3인 농도를 기준으로 검출한계는 ~5ppm이었으며 표준물질을 이용하여 얻은 검정곡선의 경우 농도가 10~100ppm의 범위에서 ~0.99 이상의 상관계수를 갖는 좋은 직선성을 보였으며, 이러한 결과를 바탕으로 분석한 결과 BFA의 경우 음이온 계면활성제의 각 성분은 octanoate, decanoate, dodecanoate, tetradecanoate, hexadecanoate등이었으며 상대비는 각각 1.0 : 1.0 : 6.5 : 2.1 : 0.8이었다.

• The Journal of Asian Finance, Economics and Business
• /
• 제7권8호
• /
• pp.197-204
• /
• 2020

Nowadays, many construction engineering and technology enterprises are evolving to find that prosperity is driven and inspired by an open economy with dynamic markets and fierce multifaceted competition. Besides brand and product uniqueness, the ability to quickly provide customers with quotes are matters of concern. Such a requirement for prompt cost estimation of construction investment projects with the use of a construction price index poses a significant challenge to contractors. This is because the nature of the construction industry is shaped by changes in domestic and foreign economic factors, socio-financial issues, and is under the influence of various micro and macro factors. This paper presents a fuzzy decision-making approach for calculating critical factors that affect the construction price index. A qualitative approach was implemented based on in-depth interviews of experts in the construction industry in Vietnam. A synthetic comparison matrix was calculated using Buckley approach. The CoA approach was applied to defuzzified the fuzzy weights of factors that affect the construction price index. The research results show that the top five critical factors affecting the construction price index in Vietnam are (1) consumer price index, (2) gross domestic product, (3) basic interest rate, (4) foreign exchange rate, and (5) total export and import.

• The Journal of Asian Finance, Economics and Business
• /
• 제9권10호
• /
• pp.39-48
• /
• 2022

This research aims to investigate the application of Keynes's theory in Indonesia, particularly in solving unemployment and poverty problems through government spending, economic growth, and human resource capacity. The basic concepts of the Keynesian theory were used as a method, through which government spending was harnessed toward economic growth in reducing unemployment and poverty rate. The analytical materials used were panel data for the 2017-2021 period in Central Java, Indonesia. The analytical methodology used was a multiple regression experimental design in selecting the best model according to Keynes's theory, especially for overcoming formidable problems. The main results showed that large Government spending program is ineffective in encouraging pro-growth, pro-job, pro-poor, and pro-equity development policy strategies. The causes of this failure include the violation of Keynes' assumptions about rationality and the low quality of education investment, which do not encourage productive and innovative entrepreneurship, as well as self-employment opportunities. As a result, government spending, including subsidies and direct financial assistance, used to implement the macroeconomic monetary, unstructured, and fiscal policy system is insufficient to significantly reduce the enormous difficulties. The main research results confirm that human capital capacity is the key to mitigating and reducing unemployment and poverty.

• 분석과학
• /
• 제12권2호
• /
• pp.166-170
• /
• 1999

A ceramic floor with improved thermal conductivity and efficiency has been developed in this study. The new ceramic floor minimizes the shrinkage rate to below 0.07% and shows almost no cleavage. There is no need to repaire the ceramic floor because its bottom surface is flat. It especially shows an excellent perfomance in the test of a compressive strength ($300kg/cm^2$ based on 28 days), a flexural strength ($64kg/cm^2$ based on 28 days), and a convenient pressing. It is lighter than the present floor and it is expected to be applicable for a self-leveling ceramic motar in the residences and apartments. It shows an excellent character in the thermal conductivity and other physical properties compare to the present cement mortar.

• 분석과학
• /
• 제8권3호
• /
• pp.397-404
• /
• 1995

Three Arsenazo I-XAD Chelating resins, with different surface areas and pore sizes were synthesized and characterized. The total sorption capacities of these chelating resins for Cu(II) at pH 5.0 by batch method decreased as follows, Arsenazo I-XAD-16(0.59mmol/g)>Arsenazo I-XAD-4(0.56mmol/g)>Arsenazo I-XAD-2(0.38mmol/g). The sorption and desorption properties of Arsenazo I-XAD-16 chelating resins for U(VI), Th(IV), Hf(IV), Zr(IV), Ni(II), Mn(II), Cd(II). and Cu(II) were studied by both batch and elution method. The Arsenazo I-XAD-16 chelating resin was successfully applied to the separation and concentration of trace U(VI) and Th(IV) in sea and waste waters.

• Natural Product Sciences
• /
• 제18권3호
• /
• pp.171-176
• /
• 2012

We previously isolated cordycepin, guanosine and tryptophan from Cordyceps militaris as antiadipogenic constituents. For the quality control of C. militaris for anti-adipogenic activity, simultaneous analytical method using high-performance liquid chromatography (HPLC)-diode array detection (DAD) was developed and validated. Quantitation of these compounds in various Cordyceps samples from different sources and various extraction methods were conducted using developed method. Our study shows that natural Cordyceps and host insect possess higher content than cultured ones and fruiting bodies, respectively. The content of cordycepin showed great difference in different C. militaris samples whereas trytophan content was similar in tested samples. Addition of water to extraction solvent greatly increased the yield of guanosine and tryptophan. High temperature and longer extraction time increased yield of guanosine, whereas the content of trytophan was decreased in high temperature during extraction with water. Extraction using ultrasonic apparatus slightly increased extraction efficiency. Cordycepin, however, has little variation in different extraction method tested. Strong anti-adipogenic activity was observed in the samples that contain all the three constituents. Taken together, quantitation of these compounds using developed analytical method might provide basic requirement for the anti-adipogenic activity of C. militaris.

• 분석과학
• /
• 제15권6호
• /
• pp.567-573
• /
• 2002

국내에서 석탄을 이용하는 발전소에서 발생되는 비산회의 최대 재활용처는 콘크리트 혼화제로의 사용인데, 여기에 사용되는 비산회에 미연탄소분이 많게되면, 탄소분에 의한 콘크리트의 질 저하가 유발된다. 현재 콘크리트 혼화제로 공급되고 있는 비산회는 미연탄소분의 함량을 낮추기 위해 정제과정을 거치고 있다. 이 과정에서 발생되는 부산물인 미연탄소분은 폐기물로서 전량 매립되고 있다. 본 연구에서는 비산회로부터 부선법으로 미연탄소분을 추출 정제하고, 이 미연탄소분을 재활용하기 위한 기초 연구의 하나로 탄소분의 형태와 모양을 조사하였다. 탄소분의 형태와 탄소분에 함유된 회분의 화학적 조성특성은 주사 전자현미경과 이에 부착되어 있는 에너지 분산형 X-선 형광분석기를 이용하여 파악하였다.