• Advances in aircraft and spacecraft science
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• v.9 no.6
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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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• v.15 no.5
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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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• v.14 no.7
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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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• v.16 no.13
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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.

• The Journal of the Acoustical Society of Korea
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• v.20 no.5
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• pp.76-82
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• 2001

Because the biological tissue with inhomogeneous acoustic properties does not keep a particular shape, the measurement of propagation characteristics of ultrasonic fields by the conventional scanning method with a miniature hydrophone is difficult. In this study, a two-dimensional may hydrophone was fabricated using the PVDF (Polyvinylidene fluoride) piezo-electric film and a ultrasonic field measurement system with it was established. For the acoustic field produced by a circular plan transducer with center frequency of 2.25㎒ and 13㎜ in diameter, it was possible to make a fairly accurate field measurement using the hydrophone system. The attenuation coefficients at 2.25 ㎒ for biological tissues were 0.7∼1.3 dB/cm(average; 1.0 dB/cm) in bovine liver, 1.0∼1.8 dB/cm (average; 1.6 dB/cm) in pig liver, 0.9∼2,9 dB/cm(average: 2.1 dB/cm) in bovine muscles, 1.7∼3.3 dB/cm (average; 2.5 dB/cm) in pig muscles.

• BMB Reports
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• v.42 no.11
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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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• v.17 no.3
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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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• v.14 no.9
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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.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.7
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• pp.26-33
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• 1999

In order to examine the effect of beam location n the performance of bridge type piozoresistive silicon accelerometer, three sensors having different location of beams were simulated by FEN(finite element method) and fabricated by RIE(reactive ion etching) and KOH etching method using SDB(silicon direct bonding) wafer, Results of the FEM simulation present that the 1st resonace frequency and Z axis sensitivity of each sensor are identical but the 2nd, and the 3rd resonace frequency and X, Y axis sensitivity are different. Even though the 1st resonance frequency and Z axis sensitivity measured from fabricated sensors do not perfectly coincide with each other, all 3 type sensors present 180 ~ 220N/G of Z sensitivity at 5 V supply voltage and 1.3 ~ 1.7kHz of the 1st resonance frequency and about 2% of lateral sensitivity.

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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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.