• Asian Pacific Journal of Cancer Prevention
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• 제15권15호
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• pp.6437-6441
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• 2014

Background: Oridonin isolated from Rabdosia rubescens, a plant used to treat cancer in Chinese folk medicine, is one of the most important antitumor active ingredients. Previous studies have shown that oridonin has antitumor activities in vivo and in vitro, but little is known about cell cycle effects of oridonin in gastric cancer. Materials and Methods: MTT assay was adopted to detect the proliferation inhibition of SGC-7901 cells, the cell cycle was assessed by flow cytometry and protein expression by Western blotting. Results: Oridonin could inhibit SGC-7901 cell proliferation, the $IC_{50}$ being $15.6{\mu}M$, and blocked SGC-7901 cell cycling in the $G_2/M$ phase. The agent also decreased the protein expression of cyclinB1 and CDK1. Conclusions: Oridonin may inhibit SGC-7901 growth and block the cells in the $G_2/M$ phase by decreasing Cdk1 and cyclinB1 proteins.

• 한국정보처리학회논문지
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• 제7권5호
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• pp.1464-1473
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• 2000

본 논문에서는 최근 상호연결망 위상으로 관심을 받고 있는 (n,k)-스티 그래프에 대한 사이클 특성을 분석한다.(n,k)-스티 그래프의 그래프 이론적 특성을 바탕으로 (n,k)-스티 그래프가 다양한 종류의 사이클들을 보유하고있는 범사이클(pancyclic)특성을 지니고 있음을 밝히고 해당 사이클들을 찾을 수 있는 알고리즘을 제시한다. 본 논문에서제안하고 있는 기법은 그래프자체의 체귀적 성질을 이용한 하형식(top-down)방식으로써 부-그래프들로 구성된 확장된 개념의 사이클들에 "차원확장"이라는 연산을 연속적으로 적용함으로써 원하는 사이클로 구체화해 가는 과정으로 진행하게 된다. 이러한 기법의 적용 결과 구성되는 사이클은 최소한의 한정된 부-그래프들로 밀집되어 모이는 경향이 있어 노드 또는 예지심에 서로 중복이 없이 독립된(disjoint) 사이클을 찾는 문제 등의 응용분야로 확대적용의 가능성이 있다. 본 연구 결과는 (n,k)-스티 그래프에 대한 그래프 이론적 관점에서의 댐사이클 특성을 분석한 이론적 의미와 더불어 해당 상호연결망 구조를 갖는 다중컴퓨터시스템에서의 메시지 라우팅이나 자원 할당 및 스케쥴링과 관련된 분야로의 응용가능성을 함께 의미하고 있다.

• Journal of Power Electronics
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• 제16권1호
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• pp.227-237
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• 2016

A novel digital current control strategy for digitally controlled DC-DC switching converters, referred to as Adjacent Cycle Sampling (ACS), is proposed in this paper. For the ACS current control strategy, the available time interval from sampling the current to updating the duty ratio, is approximately one switching cycle. In addition, it is independent of the duty ratio. As a result, the contradiction between the processing speed of the hardware and the transient response speed can be effectively relaxed by using the ACS current control strategy. For digitally controlled buck DC-DC switching converters with trailing-edge modulation, digital current control algorithms with the ACS control strategy are derived for three different control objectives. These objectives are the valley, average, and peak inductor currents. In addition, the sub-harmonic oscillations of the above current control algorithms are analyzed and eliminated by using the digital slope compensation (DSC) method. Experimental results based on a FPGA are given, which verify the theoretical analysis results very well. It can be concluded that the ACS control has a faster transient response speed than the time delay control, and that its requirements for hardware processing speed can be reduced when compared with the deadbeat control. Therefore, it promises to be one of the key technologies for high-frequency DC-DC switching converters.

• Nuclear Engineering and Technology
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• 제55권4호
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• pp.1439-1447
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• 2023

The fuel cycle characteristics of the IVG.1M reactor were studied within the framework of the research reactor conversion program to modernize the IVG.1M reactor. Optimum use of the nuclear fuel and reactor was achieved through routine methods which included partial fuel reloading combined with scheduled maintenance operations. Since, the additional problem in planning the fuel cycle of the IVG.1M reactor was the poisoning of the beryllium parts of the core, reflector, and control system. An assessment of the residual power and composition of spent fuel is necessary for the selection and justification of the technology for its subsequent management. Computational studies were performed using the MCNP6.1 program and the neutronics model of the IVG.1M reactor. The proposed scheme of annual partial fuel reloading allows for maintaining a high reactor reactivity margin, stabilizing it within 2-4 β_eff for 20 years, and achieving a burnup of 9.9-10.8 MW × day/kg U in the steady state mode of fuel reloading. Spent fuel immediately after unloading from the reactor can be placed in a transport packaging cask for shipping or safely stored in dry storage at the research reactor site.

• 가족자원경영과 정책
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• 제16권1호
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• pp.85-101
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• 2012

This study aims to identify the propensity to consume and housing characteristics according to life cycle as the main independent variable. It also tries to understand the consumption power and housing style of each cycle and analyze whether there are differences between each life cycle, ultimately aiming to match the propensity to consume and housing style with each cycle. For empirical analysis, on and off-line surveys of 488 people were collected and analyzed by cross analysis, factor analysis and analysis of variance. The prime research findings are as follows: First of all, factor analysis on propensity to consume showed four main sub-factors as rational consumption, conspicuous consumption, trend consumption, and status consumption. Secondly, current and preferred housing styles ranked from modern, natural, casual, classic and romantic, which proved that people are currently housed in preferred housing styles. Thirdly, in case of housing-related characteristics of life cycles, the size of the house increased as the levels progressed, and then decreased at level 6 when the children grew into adulthood. The majority of the population was paying a monthly rent, a few were leasing, and a very few owned their housing. 58% were living in apartments, but in levels 1-2, more were living in row houses and high-rise residential buildings, while in level 6 it was detached houses. Fourthly, the propensity to consume according to life cycle tended to shift from conspicuous and trend-based consumption to rational consumption as the cycles progressed. Fifthly, the preferred housing styles were modern and natural styles, regardless of life cycle. These study results can be applied to product development and marketing activities based on their accurate analysis of customers' needs, which can thus bring further customer satisfaction.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 I
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• pp.499-503
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• 2001

Fatigue behavior of reinforced concrete (RC) elements has been experimentally and analytical investigated. Fatigue behavior influenced by longitudinal reinforcement ratio, strength of concrete and load ratio P／sub u／／P／sub o／. The purpose of these studies is to propose an empirical formula for fatigue behavior on basis of experimental results. Also an analytical method to predict the crack propagation of RC beams has been developed based on the relationships between bond stress and slip.

• 대한수학회논문집
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• 제28권4호
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• pp.857-863
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• 2013

In this paper, we prove that the total domination number of a $P_6$-free graph of order $n{\geq}3$ and minimum degree at least one which is not the cycle of length 6 is at most $\frac{n+1}{2}$, and the bound is sharp.

• Molecules and Cells
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• 제38권6호
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• pp.518-527
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• 2015

Controlled release of medications remains the most convenient way to deliver drugs. In this study, we precipitated gold nanoparticles with quercetin. We loaded gold-quercetin into poly(DL-lactide-co-glycolide) nanoparticles (NQ) and tested the biological activity of NQ on HepG2 hepatocarcinoma cells to acquire the sustained release property. We determined by circular dichroism spectroscopy that NQ effectively caused conformational changes in DNA and modulated different proteins related to epigenetic modifications and c ell cycle control. The mitochondrial membrane potential (MMP), reactive oxygen species (ROS), cell cycle, apoptosis, DNA damage, and caspase 3 activity were analyzed by flow cytometry, and the expression profiles of different anti- and pro-apoptotic as well as epigenetic signals were studied by immunoblotting. A cytotoxicity assay indicated that NQ preferentially killed cancer cells, compared to normal cells. NQ interacted with HepG2 cell DNA and reduced histone deacetylases to control cell proliferation and arrest the cell cycle at the sub-G stage. Activities of cell cycle-related proteins, such as $p21^{WAF}$, cdk1, and pAkt, were modulated. NQ induced apoptosis in HepG2 cells by activating p53-ROS crosstalk and induces epigenetic modifications leading to inhibited proliferation and cell cycle arrest.

• Natural Product Sciences
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• 제19권2호
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• pp.155-159
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• 2013

Honokiol, a naturally occurring neolignan mainly found in Magnolia species, has exhibited a potential anti-proliferative activity in human cancer cells. However, the growth inhibitory activity against hepatocellular carcinoma cells and the underlying molecular mechanisms has been poorly determined. The present study was designed to examine the anti-proliferative effect of honokiol in SK-HEP-1 human hepatocellular cancer cells. Honokiol exerted anti-proliferative activity with cell-cycle arrest at the G0/G1 phase and sequential induction of apoptotic cell death. The cell-cycle arrest was well correlated with the down-regulation of checkpoint proteins including cyclin D1, cyclin A, cyclin E, CDK4, PCNA, retinoblastoma protein (Rb), and c-Myc. The increase of sub-G1 peak by the higher concentration of honokiol ($75{\mu}M$) was closely related to the induction of apoptosis, which was evidenced by decreased expression of Bcl-2, Bid, and caspase-9. Hohokiol was also found to attenuate the activation of signaling proteins in the Akt/mTOR and ERK pathways. These findings suggest that the anti-proliferative effect of honokiol was associated in part with the induction of cell-cycle arrest, apoptosis, and dow-nregulation of Akt/mTOR signaling pathways in human hepatocellular cancer cells.

• 한국관광식음료학회지:관광식음료경영연구
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• 제17권1호
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• pp.1-20
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• 2006

The family life cycle is a useful indicator of consumer behavior, as well as the family life cycle concept utilizes a combination of demographic and socioeconomic variables that best explains the changes in the construct of the family. The family decision-making research has frequently examined role relationship between husband and wife across stages and sub-decisions. The objective of this research is to measure children and parents' perceptions of the influence of the decision-making process for a family dining-out experience, and to determined the customers' choice behavior of restaurants according to isolated factors underlying the important attributes of the restaurants, and finally authors applied a market segmentation approach by capturing customers' preference of restaurant attributes in family dining-out situation and to investigated influence of the family decision making for family dining out in family life cycle. For practitioner, marketing implications are provided and recommendations for future research are also discussed.