• Asian Pacific Journal of Cancer Prevention
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• 제17권5호
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• pp.2719-2722
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• 2016

Circulatory miR-133a is a marker shared by several types of cancer. In this study we evaluated the feasibility of using miR-133a levels in gastric juice to screen for gastric cancer. A total of 204 samples of gastric juice and mucosa from gastric cancer, atrophic gastritis, gastric ulcer, superficial gastritis and healthy cases were collected by gastroscopy. The results showed that miR-133a levels in gastric juice and carcinoma tissues of patients with gastric cancer were significantly downregulated and positively correlated. Moreover, miR-133a in gastric juice has high operability, high reliability, high sensitivity, high specificity and relative stability, fit for clinical diagnosis of gastric cancer.

• Journal of Electrical Engineering and Technology
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• 제12권2호
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• pp.820-829
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• 2017

Vegetable oil dielectrics have been used in transformers as green alternatives to mineral insulating oils for about twenty years, because of their advantages of non-toxic, biodegradability, and renewability. However, the viscosity of vegetable oils is more than 3 times of mineral oils, which means a poor heat dissipation capacity. To get low-viscosity dielectrics, transesterification and purification were performed to prepare vegetable oil methyl esters in this study. Electrical and physical properties were determined to investigate their potential as dielectrics. The results showed that the methyl ester products had good dielectric strengths, high water saturation and enough fire resistance. The viscosities (at $40^{\circ}C$) were 0.2 times less than FR3 fluid, and 0.7 times less than mineral oil, which indicated superior cooling capacity as we expected. With the assistance of 0.5 wt% pour point depressants, canola oil methyl ester exhibited the lowest pour point ($-26^{\circ}C$) among the products which was lower than FR3 fluid ($-21^{\circ}C$) and 25# mineral oil ($-23^{\circ}C$). Thus, canola oil methyl ester was the best candidate as a low-viscosity vegetable oil-based dielectric. The low-viscosity fluid could extend the service life of transformers by its better cooling capacity compared with nature ester dielectrics.

• Advances in nano research
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• 제6권2호
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• pp.163-182
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• 2018

Based on the Reissner mixed variational theorem (RMVT), the authors present a nonlocal Timoshenko beam theory (TBT) for the nonlinear free vibration analysis of multi-walled carbon nanotubes (MWCNT) embedded in an elastic medium. In this formulation, four different edge conditions of the embedded MWCNT are considered, two different models with regard to the van der Waals interaction between each pair of walls constituting the MWCNT are considered, and the interaction between the MWCNT and its surrounding medium is simulated using the Pasternak-type foundation. The motion equations of an individual wall and the associated boundary conditions are derived using Hamilton's principle, in which the von $K{\acute{a}}rm{\acute{a}}n$ geometrical nonlinearity is considered. Eringen's nonlocal elasticity theory is used to account for the effects of the small length scale. Variations of the lowest frequency parameters with the maximum modal deflection of the embedded MWCNT are obtained using the differential quadrature method in conjunction with a direct iterative approach.

• Smart Structures and Systems
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• 제16권5호
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• pp.781-806
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• 2015

A unified formulation of finite layer methods (FLMs), based on the Reissner mixed variational theorem (RMVT), is developed for the three-dimensional (3D) coupled electro-elastic analysis of simply-supported, functionally graded piezoelectric material (FGPM) plates with open- and closed-circuit surface conditions and under electro-mechanical loads. In this formulation, the material properties of the plate are assumed to obey an exponent-law varying exponentially through the thickness coordinate, and the plate is divided into a number of finite rectangular layers, in which the trigonometric functions and Lagrange polynomials are used to interpolate the in- and out-of-plane variations of the primary field variables of each individual layer, respectively, such as the elastic displacement, transverse shear and normal stress, electric potential, and normal electric displacement components. The relevant orders used for expanding these variables in the thickness coordinate can be freely chosen as the linear, quadratic and cubic orders. Four different mechanical/electrical loading conditions applied on the top and bottom surfaces of the plate are considered, and the corresponding coupled electro-elastic analysis of the loaded FGPM plates is undertaken. The accuracy and convergence rate of the RMVT-based FLMs are assessed by comparing their solutions with the exact 3D piezoelectricity ones available in the literature.

• Journal of Magnetics
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• 제21권3호
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• pp.387-392
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• 2016

Lower flux leakage designs have become important in the development of microspeakers used in thin and miniaturized mobile phones. We propose four methods to reduce the flux leakage of the magnetic circuit in a microspeaker. Optimization was performed based on the proposed approach by using the response surface method. Electromagnetic analyses were conducted using the finite element method. Experimental results are in good agreement with the simulated results obtained in one degree-of-freedom analysis from 100 to 5 kHz. Both the simulated and experimental results confirm that one of the proposed methods is much more effective in reducing flux leakage than the other methods. In the optimized method, compared with a default approach, the average radial flux density in the air gap decreased only by 5.5%, the maximum flux leakage was reduced by 28.6%, and the acoustic performance at primary resonance decreased by 0.45 dB, which gap is indiscernible to the human ear.

• 천문학회지
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• 제37권5호
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• pp.597-600
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• 2004

A substantial number of processes have been suggested as possible contributors to the extragalactic $\gamma$-ray background (EGRB). Yet another contribution to this background will be emission produced in hadronic interactions of cosmic-ray protons with the cluster thermal gas; this class of cosmic rays (CRs) has been shown to be responsible for the EUV emission in the Coma Cluster of galaxies. In this paper we assume the CRs in the Coma Cluster is prototypic of all clusters and derive the contribution to the EGRB from all clusters over time. We examine two different possibilities for the scaling of the CR flux with cluster size: the number density of the CRs scale with the number density of the thermal plasma, and alternatively, the energy density of the CRs scale with the energy density of the plasma. We find that in all scenarios the EGRB produced by this process is sufficiently low that it will not be observable in comparison with other mechanisms that are likely to produce an EGRB.

• BMB Reports
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• 제43권5호
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• pp.330-336
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• 2010

5-Aminolevulinate (ALA) is well-known as an essential biosynthetic precursor of all tetrapyrrole compounds, which has been suggested to improve plant salt tolerance by exogenous application. In this work, the gene encoding aminolevulinate synthase (ALA-S) in yeast (Saccharomyces cerevisiae Hem1) was introduced into the genome of Arabidopsis controlled by the Arabidopsis thaliana HemA1 gene promoter. All transgenic lines were able to transcribe the YHem1 gene, especially under light condition. The chimeric protein (YHem1-EGFP) was found co-localizing with the mitochondria in onion epidermal cells. The transgenic Arabidopsis plants could synthesize more endogenous ALA with higher levels of metabolites including chlorophyll and heme. When the $T_2$ homozygous seeds were cultured under NaCl stress, their germination and seedling growth were much better than the wild type. Therefore, introduction of ALA-S gene led to higher level of ALA metabolism with more salt tolerance in higher plants.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.287-292
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• 2005

Hybrid시스템의 운전결과 황화수소의 removal efficiency는 황화수소의 inlet load가 $200g/m^{3}/h$에서 removal efficiency가 급격히 감소하여 약 60%의 수준을 유지하였다. 또한 톨루엔에 대한 removal efficiency는 거의 100%를 유지하다가 톨루엔의 inlet load가 $644g/m^{3}/h$로 증가할 때에는 약 60%로 감소하였다. 이와 같은 Hybrid시스템 운전결과로 부터 바이오필터만을 이용하여 황화수소와 톨루엔을 동시처리할 때보다 removal efficiency가 제고되었음이 관찰되었다.

• 한국정보시스템학회지:정보시스템연구
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• 제19권3호
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• pp.127-147
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• 2010

전자상거래의 급속한 발전 속에서 기업들은 세계적 시장에서 경쟁력을 지니기 위해 전자상거래를 이용하여 상품판매, 서비스 제공, 고객과 소통하고자 한다. 그러나, 기존의 연구들은 TAM 모형을 통한 상호관계나 선행관계에만 초점을 맞추고 있기 때문에 좀 더 확장한 모형이 필요하다. 본 연구에서는 상품정보와 서비스 제공수준은 소비자 행동에 영향을 미치는 중요한 요인이지만 연구가 충분치 못한 실정이다. 따라서 본 연구의 목적은 첫째, 상품정보제공수준과 서비스제공수준에 따른 소비자 태도 차이를 조망하고자 한다. 둘째, 기존에 연구가 미약하였던 상품정보제공수준 및 서비스제공수준과 기존에 인지된 가치, 인지된 위험, 구매의도와 구전의도간의 상호인과관계를 조망하고자 한다. 본 연구의 결과는 다음과 같다. 첫째, 상품정보제공수준과 서비스제공수준에 따라 소비자 태도 차이에는 차이가 있었다. 둘째, 상품정보제공수준과 서비스제공수준에 따라 소비자들이 인지된 가치, 인지된 위험, 구매의도, 구전효과에는 차이가 있었다. 셋째, 변수들간에 상호인과관계와 선행관계가 존재하였다. 상품정보제공수준과 서비스 제공수준은 인지된 가치와 인지된 위험에 각각 직접적인 영향을 미쳤다. 뿐만 아니라, 인지된 가치는 인지된 위험, 구매의도, 구전효과에, 인지된 위험은 구매의도와 구전효과에 직접적인 영향을 나타내었다.

• Asian-Australasian Journal of Animal Sciences
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• 제23권1호
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• pp.98-105
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• 2010

A total of 16 crossbred post-weaning pigs (10.64${\pm}$0.27 kg BW) were individually penned and assigned to one of two treatments to investigate the influences of diquat-induced oxidative stress on performance and arginine metabolism. Pigs in the oxidative stress group were injected intra-peritoneally with 10 mg/kg BW of diquat, while the control group were injected with isotonic saline. All pigs were fed ad libitum. The experiment lasted for 7 days. The results indicated that compared with control treatment, oxidative stress induced by diquat significantly decreased average daily gain, intake and feed conversion. The treatment decreased activities of antioxidant enzymes, increased concentration of malondialdehyde in plasma, increased cationic amino acid transporter-1 mRNA level and activity of ornithine aminotransferase and concentrations of arginine and citrulline in the jejunum, decreased the concentrations of arginine in plasma and kidney, and decreased induced nitric oxide synthase mRNA level. It is concluded that oxidative stress induced by diquat can influence absorption and metabolism of arginine and consequently modify the requirement of arginine for post-weaning pigs.