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GMO standards, endogenous policy and the market for information[taliem.ir]

GMO standards, endogenous policy and the market for information

The paper develops a composite index of GMO standards restrictiveness for 60 countries, assigning objective scores to six different regulatory dimensions. Using this index and its components, we empirically investigate the political and economic determinants of GMO regulations for 55 countries, controlling for spatial autocorrelation. Results show that many of the determinants highlighted in the theoretical literature, such as the structure of the agricultural sector and the institutional environment are important determinants of the restrictiveness of the GMO regulation. As a key result there emerges a prominent role of the market for information, showing that the structure of domestic mass media (public vs. private) is an important driver of GMO standards
An experimental and numerical study on heat transfer[taliem.ir]

An experimental and numerical study on heat transfer enhancement for gas heat exchangers fitted with porous media

The present experimental and numerical work investigates the effect of metallic porous materials, inserted in a pipe, on the rate of heat transfer. The pipe is subjected to a constant and uniform heat flux. The effects of porosity, porous material diameter and thermal conductivity as well as Reynolds number on the heat transfer rate and pressure drop are investigated. The results are compared with the clear flow case where no porous material was used. The results obtained lead to the conclusion that higher heat transfer rates can be achieved using porous inserts at the expense of a reasonable pressure drop. Also, it is shown that for an accurate simulation of heat transfer when a porous insert is employed its effective thermal conductivity should be carefully evaluated.