• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.12
• /
• pp.7243-7249
• /
• 2013

Numerous studies have been conducted regarding association between TNF-${\alpha}$ and oral cancer risk, but the results remain controversial. The present meta-analysis is performed to acquire a more precise estimation of relationships. Databases of Pubmed, the Cochrane library and the China National Knowledge Internet (CNKI) were retrieved until August 10, 2013. Pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated with fixed- or random-effect models. The heterogeneity assumption was assessed by I-squared test. Among the eight included case-control studies, all were focused on TNF-${\alpha}$-308G>A and four also concerned the TNF-${\alpha}$-238G>A polymorphism. It was found that oral cancer risk were significant decreased with the TNF-${\alpha}$-308G>A polymorphism in the additive genetic model (GG vs. AA, OR=0.19, 95% CI: [0.04, 1.00], P=0.05, I2=68.9%) and the dominant genetic model (GG+GA vs. AA, OR=0.22, 95% CI: [0.06, 0.82], P=0.03, I2=52.4%); however, no significant association was observed in allele contrast (G vs. A, OR=0.70, 95% CI: [0.23, 2.16], P=0.54, I2=95.9%) and recessive genetic models (GG vs. GA+AA, OR=0.72, 95% CI: [0.33, 1.57], P=0.41, I2=93.1%). For the TNF-${\alpha}$-238G>A polymorphism, significant associations with oral cancer risk were found in the allele contrast (G vs. A, OR=2.75, 95% CI: [1.25, 6.04], P=0.01, I2=0.0%) and recessive genetic models (GG vs. GA+AA, OR=2.23, 95%CI: [1.18, 4.23], P=0.01, I2=0.0%). Conclusively, this meta-analysis indicates that TNF-${\alpha}$ polymorphisms may contribute to the risk of oral cancer. Allele G and the GG+GA genotype of TNF-${\alpha}$-308G>A may decrease the risk of oral cancer, while allele G and the GG genotype of TNF-${\alpha}$-238G>A may cause an increase.

• Korean Chemical Engineering Research
• /
• v.53 no.1
• /
• pp.46-52
• /
• 2015

A leaching kinetics was conducted for the purpose of recovery of praseodymium in sulfuric acid ($H_2SO_4$) from REE slag concentrated by the smelting reduction process in an arc furnace as a reactant. The concentration of $H_2SO_4$ was fixed at an excess ratio under the condition of slurry density of 1.500 g slag/L, 0.3 mol $H_2SO_4$, and the effect of temperatures was investigated under the condition of 30 to $80^{\circ}C$. As a result, praseodymium oxide ($Pr_6O_{11}$) existing in the slag was completely converted into praseodymium sulfate ($Pr_2(SO_4)_3{\cdot}8H_2O$) after the leaching of 5 h. On the basis of the shrinking core model with a shape of sphere, the first leaching reaction was determined by chemical reaction mechanism. Generally, the solubility of pure REEs decreases with the increase of leaching temperatures in sulfuric acid, but REE slag was oppositely increased with increasing temperatures. It occurs because the ash layer included in the slag is affected as a resistance against the leaching. By using the Arrhenius expression, the apparent activation energy of the first chemical reaction was determined to be $9.195kJmol^{-1}$. In the second stage, the leaching rate is determined by the ash layer diffusion mechanism. The apparent activation energy of the second ash layer diffusion was determined to be $19.106kJmol^{-1}$. These relative low activation energy values were obtained by the existence of unreacted ash layer in the REE slag.

• Journal of health informatics and statistics
• /
• v.43 no.4
• /
• pp.290-299
• /
• 2018

Objectives: This study aimed to evaluate the change in weight and heart rate associated with the use of phentermine through meta-analysis based on the published literatures. Methods: Eight electronic databases, PubMed, EMBASE, Cochrane library, and five domestic databases were used to search the literature. Randomized controlled trials that evaluated the change in weight and heart rate with the use of phentermine compared with placebo were included in this study. The fixed-effect model weighted by the Mantel-Haenszel method was used in the meta-analysis, and the random-effects model was used when heterogeneity was present. Results: We included 12 studies comprising 677 patients. The change in weight observed with the use of phentermine (SMD = -1.37, 95% CI: -1.55, -1.19) was statistically significant compared with that observed with placebo. As per the subgroup analysis results, the change in weight by publication year, country, phentermine dosage, follow-up check was not heterogeneous. The change in heart rate observed with the use of phentermine (SMD = 0.64, 95% CI: 0.35, 0.92) was significant compared with that observed with placebo. Conclusions: Weight loss and increased heart rate were confirmed in phentermine compared with placebo.

• Animal Bioscience
• /
• v.34 no.3_spc
• /
• pp.434-442
• /
• 2021

Objective: This study aims to evaluate the influence of dietary flavonoids on the growth performance, blood and intestinal profiles, and carcass characteristics of broilers by employing a meta-analysis method. Methods: A database was built from published studies which have reported on the addition of various levels of flavonoids from herbs into broiler diets and then monitored growth performance, blood constituents, carcass proportion and small intestinal morphology. A total of 42 articles were integrated into the database. Several forms of flavonoids in herbs were applied in the form of unextracted and crude extracts. The database compiled was statistically analyzed using mixed model methodology. Different studies were considered as random effects, and the doses of flavonoids were treated as fixed effects. The model statistics used were the p-values and the Akaike information criterion. The significance of an effect was stated when its p-value was <0.05. Results: Dietary flavonoids increased (quadratic pattern; p<0.05) the average daily gain of broilers in the finisher phase. There was a reduction (p<0.01) in the feed conversion ratio of the broilers both in the starter (linear pattern) and finisher phases (quadratic pattern). The mortality rate tended to decrease linearly (p<0.1) with the addition of flavonoids, while the carcass parameter was generally not influenced. A reduction (p<0.001) in cholesterol and malondialdehyde concentrations (both linearly) was observed, while super oxide dismutase activity increased linearly (p<0.001). Increasing the dose of flavonoids increased (p<0.01) the villus height (VH) and villus height and crypt depth (VH:CD) ratio (p<0.05) in the duodenum. Similarly, the VH:CD ratio was elevated (p<0.001) in the jejunum following flavonoid supplementation. Conclusion: Increasing levels of flavonoids in broilers diet leads to an improvement in growth performance, blood constituents, carcass composition and small intestinal morphology.

• Korean Journal of Remote Sensing
• /
• v.38 no.5_2
• /
• pp.793-810
• /
• 2022

Synthetic Aperture Radar (SAR) is considered to be suitable for near real-time inundation monitoring. The distinctly different intensity between water and land makes it adequate for waterbody detection, but the intrinsic speckle noise and variable intensity of SAR images decrease the accuracy of waterbody detection. In this study, we suggest two modules, named 'morphology module' and 'edge-enhanced module', which are the combinations of pooling layers and convolutional layers, improving the accuracy of waterbody detection. The morphology module is composed of min-pooling layers and max-pooling layers, which shows the effect of morphological transformation. The edge-enhanced module is composed of convolution layers, which has the fixed weights of the traditional edge detection algorithm. After comparing the accuracy of various versions of each module for U-Net, we found that the optimal combination is the case that the morphology module of min-pooling and successive layers of min-pooling and max-pooling, and the edge-enhanced module of Scharr filter were the inputs of conv9. This morphologic and edge-enhanced U-Net improved the F1-score by 9.81% than the original U-Net. Qualitative inspection showed that our model has capability of detecting small-sized waterbody and detailed edge of water, which are the distinct advancement of the model presented in this research, compared to the original U-Net.

• Korea Trade Review
• /
• v.43 no.3
• /
• pp.169-198
• /
• 2018

The purpose of this paper is to investigate the impact of exchange rate volatility on the export of Korean machinery intermediate goods to East Asian countries using the export demand model. In order to secure the validity of the estimation of the exchange rate volatility for the export of machinery intermediate goods, various methods of volatility measurement are used including the GARCH model, the moving average standard deviation and the 12-month fixed average standard deviation. The long-term relationship between variables was analyzed by applying the panel cointegration tests and DOLS & FMOLS panel estimations. Analysis results found that prior to the global financial crisis in 2008, the total exports of machinery and exchange rate volatility positively affect the exports of intermediate goods such as general machinery, electronic machinery and transportation equipment, but did not affect the exports of precision machinery intermediate goods. After the global financial crisis, however, exchange rate volatility negatively affected total exports and the exports of all machinery intermediate goods. When analyzing the period before and after the global financial crisis, it had a positive impact on exports of precision machinery intermediate goods and a negative effect on total exports and the exports of other machinery intermediate goods.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.11
• /
• pp.4449-4454
• /
• 2014

Aim: Helicobacter pylori (H. pylori) have been considered as a risk factor for many cancers. We conducted this meta-analysis to clarify the association between H. pylori infection and the risk of pancreatic cancer. Methods: We searched the Medicine/Pubmed and Embase databases, studies about the association between H. pylori infection and pancreatic cancer published up to Jan.2014 were included. Finally, a total of 9 studies were used for this a meta-analysis. The odds ratios (ORs) and 95% confidence interval (95%CI) of H. pylori infection on pancreatic cancer with respect to control groups were evaluated. Two authors independently assessed the methodological quality and extracted data. This meta-analysis was conducted using software, state (version 12.0) to investigate heterogeneity among individual studies and to summarize the studies. Using the fixed-effects or random-effects model, depending on the absence or presence of significant heterogeneity. Sensitivity analysis was performed to assess the influence of each individual study on the pooled ORs by omitting a single study each time. Publication bias was evaluated by funnel plot, using Egger's and Begg's tests. Results: There was no significant association between H. pylori infection and pancreatic cancer risk in the summary ORs,(OR=1.06, 95%CI: 0.74-1.37) through the random-effect method, but heterogeneity among studies was significant ($I^2$=58.9%), so we put the studies into two subgraphs (eastern and western). The results about western (OR=1.14 95%CI:0.89, 1.40) showed heterogeneity among the western countries of $I^2$=6.6%, with no significant association between Hp+ and pancreatic cancer, but the eastern countries (OR=0.62, 95%CI:0.49, 0.76), $I^2$=0, suggested that decreasing pancreas-cancer risk in subjects with Hp+ infection. Simultaneously, 7 studies examined CagA+ strains was (OR=0.84 95%CI:0.63, 1.04), $I^2$=36% with the random-effect method, subgraphs indicated that CagA+ could decrease the risk of pancreatic cancer in the eastern subjects (OR=0.66, 95%CI:0.52-0.80), but the association was not statistically significant in the western subjects (OR=0.95, 95%CI:0.73, 1.16). Conclusion: Hp+ and CagA+ infection are associated with a decreased risk of pancreatic cancer in eastern populations but have no significant associations in western countries.

• Journal of Korea Technology Innovation Society
• /
• v.21 no.1
• /
• pp.420-453
• /
• 2018

In the growth of the government's investment in national R&D project and the abuse of research expense, an effective control and management mechanism is strongly demanded. However, an excessive regulation might hinder the R&D performance, which also endangers the underlying objective of R&D policy. Especially, an excessive regulation on the R&D expenditure may damage the SMEs (Small and Medium sized Enterprises) where securing an adequate level of R&D funding is vital. This study investigates the R&D funding and R&D performance of SMEs participating in the national R&D project by using fixed effect panel model. As a result, this paper reveals the effectiveness of 'Government R&D subsidy'. However, that of 'private R&D fund' is not supported strongly. Also, this paper empirically demonstrates the efficiency of both 'Government R&D subsidy' and 'Private R&D fund' as the R&D costs are spent discretionarily (as the degree of 'Indirect Cost Ratio' increases). Especially, the effectiveness of 'Private R&D fund' can be moderated by 'Indirect Cost Ratio'. On the basis of the conclusions, this paper draws an implication that can increase R&D performance of SMEs through the interactions of manifold administrative values (i.e. effectiveness, efficiency and responsibility).

• Journal of Korea Water Resources Association
• /
• v.41 no.1
• /
• pp.75-85
• /
• 2008

The pale chub (Zacco platypus) is a dominant species that migrates locally and inhabits in rivers in Korea. The fish movement at confluences or hydraulic connections is very important especially for the life of small fish as pale chub. If main stream and off-channel habitats are connected with culverts, they would restrict the fish movement due to the high flow velocities and low depths. In foreign conturies, design flow conditions of fish friendly culvert, including flood flow capacity and fish-passage flow capacity, were assigned. Installation of culvert fishways is one way to improve the fish-passing capacity of culverts. On the contrary, in Korea, the design flow of culvert contains only the flood flow capacity. The effect of the fish passage with offset baffles was tested with the fixed velocity method in an experimental flume. As a result, An occasion velocity 1.2m/s, proportional success of pale chubs pass is maximum 20% improve than without baffle flume for energy dissipate. Offset baffle fishway(baffle height 5cm) provides that resting areas and/or a continuous channel of low velocity water in culverts. Especially, short baffle areas are domain where the pale chubs pass. And, FLOW-3D, a three dimentional numerical model, was used in order to evaluate detailed hydraulic characteristics and application possibility in a culvert fishway design.

• Journal of Biomedical Engineering Research
• /
• v.19 no.6
• /
• pp.551-562
• /
• 1998

Amultiresolution filtering algorithm based on the physical SPECT lesion detachability provides and optimal solution for SPECT reconstruction problem. Related to the previous study, we estimated the SPECT lesion detection capability by m minimum detectable lesion sizes (MDLSs), and generated m reconstruction filters which are designed to maximize the smoothing effect at a fixed MDLS-dependent resolution level $\frac{MDLS}{4\sqrt{2In2}}$. The proposed multiresolution filtering algorithm used a coarse-to-fine approach for the m-level resolution filter images obtained from these m filters for a given projection image. First, the local homogeneity is determined for every pixel of the filter images, by comparing the local variance value computed in a window centered at the pixel and the mode determined from the distribution of the local variances. Based on the local homogeneity, the pixels declared as homogeneous are chosen from the filter image of the lowest resolution, and for the other pixels the same process is repeated for the higher resolution filter images. For the non-homogeneous pixels after this pixels after this repetition process ends, the pixel values of the highest resolution filter image are substituted. From the results of the simulated experiments, the proposed multiresolution filtering algorithm showed a strong smoothing effect in the homogeneous regions and a significant resolution improvement near the edge regions of the projection images, and so produced good adaptability effects in the reconstructed images.