• Advances in aircraft and spacecraft science
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• 제9권6호
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• pp.537-551
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• 2022

The rapid decrease of fossil fuel resources and increase of environmental pollution caused by aviation industries have become a severe issue which leads to an increase in the greenhouse effect. The use of biofuel becomes an option to alleviate issues related to unrenewable resources. This study presents a computational simulation of the biofuel combustion characteristics of various alternative fuels in an annular combustion chamber designed for training aircraft. The biofuels used in this study are Sorghum Oil Methyl Ester (SOME), Spirulina Platensis Algae (SPA) and Camelina Hydrotreated Esters and Fatty Acids (CHEFA). Meanwhile, Jet-A is used as a baseline fuel. The fuel properties and combustion characteristics are being investigated and analysed. The results are presented in terms of temperature and pressure profiles in addition to the formation of NOx and soot generated from the combustion chamber. Results obtained show that CHEFA fuel is the most recommended biofuel among all four tested fuels as it is being found that it burns with 37.6% lower temperature, 15.2% lower pressure, 89.5% lower NOx emission and 8.1% lower soot emission compared with the baseline fuel in same combustion chamber geometry with same initial parameters.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.2075-2081
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• 2014

The association between glutathione-S-transferase polymorphisms (GSTM1, GSTT1 and GSTP1) and risk of acute leukemia in Asians remains controversial. This study was therefore designed to evaluate the precise association in 23 studies identified by a search of PubMed and several other databases, up to December 2013. Using random or fixed effects models odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated. Heterogeneity across studies was assessed, and funnel plots were constructed to test for publication bias. The meta-analysis showed positive associations between GST polymorphisms (GSTM1 and GSTT1 but not GSTP1) and acute leukemia risk [(OR=1.47, 95% CI 1.18-1.83); (OR=1.32, 95% CI 1.07-1.62); (OR=1.01, 95% CI 0.84-1.23), respectively] and heterogeneity between the studies. The results suggested that the GSTM1 null genotype and GSTT1null genotype, but not the GSTP1 polymorphism, might be a potential risk factors for acute leukemia. Further well-designed studies are needed to confirm our findings.

• Asian Pacific Journal of Cancer Prevention
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• 제14권7호
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• pp.4261-4265
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• 2013

Increasing scientific evidence suggests that ribonucleotide reductase M1 (RRM1) may be a powerful predictor of survival in patients with pancreatic cancer treated with adjuvant gemcitabine-based chemotherapy after operative resection, but many existing studies have yielded inconclusive results. This meta-analysis aimed to assess the prognostic role of RRM1 in predicting survival in patients with pancreatic cancer treated with gemcitabine. An extensive literature search for relevant studies was conducted on PubMed, Embase, Web of Science, Cochrane Library, and CBM databases from their inception through May 1st, 2013. This meta-analysis was performed using the STATA 12.0 software and crude hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. Eight clinical studies were included in this meta-analysis with a total of 665 pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy, including 373 patients in the high RRM1 expression group and 292 patients in the low RRM1 expression group. Our meta-analysis revealed that high RRM1 expression was associated with improved overall survival (OS) of pancreatic cancer patients (HR=1.56, 95%CI=0.95-2.17, P<0.001). High RRM1 expression also was linked to longer disease-free survival (DFS) than low RRM1 expression (HR=1.37, 95%CI=0.25-2.48, P=0.016). In conclusion, our meta-analysis suggests that high RRM1 expression may be associated with improved OS and DFS of pancreatic cancer patients treated with adjuvant gemcitabine-based chemotherapy. Detection of RRM1 expression may be a promising biomarker for gemcitabine response and prognosis in pancreatic cancer patients.

• Asian Pacific Journal of Cancer Prevention
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• 제16권13호
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• pp.5407-5413
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• 2015

Background: Published data regarding associations between the P275A polymorphism in the macrophage scavenger receptor 1 (MSR1) gene and prostate cancer (PCa) risk are inconclusive. The aim of this study was to comprehensively evaluate the genetic risk of P275A polymorphism in MSR1 gene for PCa. Materials and Methods: A systematic literature search was carried out in Pubmed, Medline (Ovid), Embase, CBM, CNKI, Weipu, and Wanfang databases, covering all available publications (last search was performed on Apr 27, 2015). Statistical analysis was performed using Revman 5.2 and STATA 10.1 software. Results: A total of 5,017 cases and 4,869 controls in 12 case-control studies were included in this meta-analysis. When all groups were pooled, there was no evidence that the P275A polymorphism had a significant association with PCa under dominant (OR=0.93, 95%CI=0.81-1.06, and p=0.28), co-dominant (homogeneous OR=0.97, 95%CI=0.56-1.68, and p=0.92; heterogeneous OR=0.93, 95%CI=0.74-1.15, and p=0.49), recessive (OR=1.10, 95%CI=0.65-1.87, and p=0.73), over-dominant (OR=0.93, 95%CI=0.75-1.15, and p=0.50), and allelic (OR=0.95, 95%CI=0.77-1.16, and p=0.61) genetic models. For stratified analyses by ethnicity and study design, no significant associations were found in the white race, the yellow race, the black race and mixed ethnicity, and the population-based case-control (PCC) and hospital-based case-control (HCC) studies under all genetic models. Conclusions: Based on our meta-analysis, the P275A polymorphism in the MSR1 gene is unlikely to be a risk factor for PCa.

• 한국음향학회지
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• 제20권5호
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• pp.76-82
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• 2001

음향특성이 균일하지 않는 생체조직은 특정의 형태 유지가 어렵기 때문에 종래의 극소형 수중청음기의 스캐닝 방법에 의한 초음파 음장 전파특성 측정이 곤란하다. 본 연구에서는 PVDF (Polyvinylidene fluoride) 압전막을 사용하여 2차원 배열 수중청음기를 제작하고, 그것에 의한 음장 측정 시스템을 구축한 후, 생체조직에 적용하였다. 중심주파수 2.25 ㎒이고 직경이 13㎜인 원형평면 트랜스듀서에 의한 실험 결과, 구축한 시스템에 의해 비교적 정밀한 음장 측정이 가능한 것을 알았으며, 그 주파수에 대해 소와 돼지의 간에서는 각각 0.7∼l.3dB/cm (평균; 1.0 dB/cm), 1.0∼l.8 dB/cm (평균; 1.6 dB/cm), 근육에서는 각각 0.9∼2.9 dB/cm (평균; 2.1dB/cm), 1.7∼3.3 dB/cm (평균: 2.5 dB/cm)의 값을 갖는 감쇠계수의 공간적 분포를 측정할 수 있었다.

• BMB Reports
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• 제42권11호
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• pp.752-757
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• 2009

Copper is essential but toxic in excess for aerobic organisms. Yeast transcription factor ACE1 functions as a sensor for copper and an inducer for the transcription of CUP1. In addition, ACE1 can activate the transcription of superoxide dismutase gene (sod1) in response to copper. In this study, we introduced the yeast ACE1 into Arabidopsis and analyzed its function in plant. Under high copper stress, the transgenic plants over-expressing ACE1 showed higher survival rate than the wild-type. We also found that over-expression of ACE1 in Arabidopsis increased the activities of SOD and POD, which were beneficial to the cell in copper buffering. Excess copper would suppress the expression of chlorophyll biosynthetic genes in Arabidopsis, RT-PCR analysis revealed that over-expression of ACE1 decrease the suppression. Together, our results indicate that ACE1 may play an important role in response to copper stress in Arabidopsis.

• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.1141-1148
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• 2016

Background: A large number of studies have been published to investigate the association between the null genotype of glutathione S-transferase T1 (GSTT1) with gastric cancer. However, the results were inconsistent and conflicting. The aim of this study was to estimate the relationship between this polymorphism in the GSTT1 gene and gastric cancer risk in Asian populations by meta-analysis. Materials and Methods: A literature search was performed in PubMed, Embase, Chinese Biomedical database (CBM), Weipu database, Wanfang database, and China National Knowledge Infrastructure database (CNKI). Statistical analysis was conducted by using Review Manager 5.3. Results: Thirty-nine studies with a total of 7,737 gastric cancer cases and 10,823 controls were included in this meta-analysis. The meta-analysis of total studies showed that the null genotype in GSTT1 was associated with increased risk of gastric cancer in Asians (OR=1.19, 95% CI=1.08-1.31, p=0.0002). Subgroup analysis showed a significant relationship between GSTT1 null genotype and gastric cancer in East-Asians, as well as in subgroup analysis of hospital-based design. On subgroup analysis by smoking status, alcohol status, Helicobacter pylori infection status, and histology type, no significant association of this polymorphism with susceptibility to gastric cancer was found. Conclusions: In conclusion, the results showed that the null genotype of GSTT1 is significantly associated with an increased risk in gastric cancer in Asian populations.

• Asian Pacific Journal of Cancer Prevention
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• 제14권9호
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• pp.5037-5041
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• 2013

Accumulated evidence has indicated that Ephrin A1 (EFNA1) is associated with angiogenesis and tumorigenesis in various types of malignancies, including colorectal cancer (CRC). In the current study, we performed an online search using the public microarray database to investigate whether EFNA1 expression might be altered in CRC tissues. We then conducted a case-control study including 306 subjects (102 cases and 204 well-matched controls) in Xiaoshan County to assess any association between genetic polymorphisms in EFNA1 and CRC susceptibility. Searches in the Oncomine expression profiling database revealed EFNA1 to be overexpressed in CRC tissue compared with adjacent normal tissue. The rs12904 G-A variant located in the 3' untranslated region (UTR) of EFNA1 was observed to be associated with CRC susceptibility. Compared with the AA homozygous genotype, those carrying GA genotype had a decreased risk of developing CRC (odds ratio (OR)=0.469, 95% confidence interval (CI): 0.225-0.977, and P=0.043). The association was stronger among smokers and tea drinkers, however, no statistical evidence of interaction between rs12904 polymorphism and smoking or tea drinking on CRC risk was found. Our results suggest that EFNA1 is involved in colorectal tumorigenesis, and rs12904 A>G polymorphism in the 3' UTR of EFNA1 is associated with CRC susceptibility. Larger studies and further mechanistic investigations are warranted to confirm our findings.

• 전자공학회논문지D
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• 제36D권7호
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• pp.26-33
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• 1999

4빔 브릿지형 압저항형 실리콘 가속도 센서에서 빔의 위치가 가속도 센서의 특성에 어떤 영향을 주는지 조사하기 위해서 빔의 위치가 서로 다른 3가지 형태의 가속도 센서를 FEM(finite element method)을 사용하여 해석하고, SDB(silicon direct bonding) 웨이퍼를 사용하여 RIE(reactive ion etching)와 KOH(potassium hydroxide) 애칭 공정으로 제조하였다. 세가지 형태의 가속도 센서에 대한 FEM 해석 경과, 첫 번째 공진 주파수와 Z축 감도는 세구조 모두 같게 나타났으나, 두 번째와 세 번째의 공진 주파수 및 X, Y축의 감도는 다른 것으로 나타났다. 제조된 가속도 센서의 특성을 살펴볼 때, 세 가지 형태의 센서는 비록 첫 번째 공진 주파수와 Z축 감도가 정확하게 일치하지는 않았지만, 첫 번째 공진 주파수는 1.3 ~ 1.7 KHz, Z축 감도는 5 V 인가시 180 ~ 220 lN/G, 타축감도는 1.7 ~ 2 %를 가지는 것으론 나타났다.

• Bulletin of the Korean Chemical Society
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• 제34권3호
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• pp.827-830
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• 2013

Investigation of an organic extract of the fruits Schisandra wilsoniana led to the isolation of two new highly oxygenated nortriterpenoids, named schilancidilactones V-W (1-2). Their structures were elucidated by spectroscopic evidence. Compounds 1-2 feature a double bond between C-7 and C-8 compared with related known nortriterpenoids isolated from the genus Schisandra. Compounds 1 and 2 were tested for their anti-HIV-1 activities and cytotoxicity. The results revealed that compounds 1 and 2 showed moderate anti-HIV-1 activities with $EC_{50}$ 3.05 and 2.87 ${\mu}g/mL$, respectively, and compound 1 showed high cytotoxicity against KB and MDA-MB-231 cell with $IC_{50}$ values of 3.18 and 5.22 ${\mu}M$, respectively.