Polytechnic University of Valencia

About: Polytechnic University of Valencia is a education organization based out in Valencia, Spain. It is known for research contribution in the topics: Catalysis & Population. The organization has 16282 authors who have published 40162 publications receiving 850234 citations.

maSigPro: a method to identify significantly differential expression profiles in time-course microarray experiments

Abstract: Motivation: Multi-series time-course microarray experiments are useful approaches for exploring biological processes. In this type of experiments, the researcher is frequently interested in studying gene expression changes along time and in evaluating trend differences between the various experimental groups. The large amount of data, multiplicity of experimental conditions and the dynamic nature of the experiments poses great challenges to data analysis. Results: In this work, we propose a statistical procedure to identify genes that show different gene expression profiles across analytical groups in time-course experiments. The method is a two-regression step approach where the experimental groups are identified by dummy variables. The procedure first adjusts a global regression model with all the defined variables to identify differentially expressed genes, and in second a variable selection strategy is applied to study differences between groups and to find statistically significant different profiles. The methodology is illustrated on both a real and a simulated microarray dataset. Availability: The method has been implemented in the statistical language R and is freely available from the Bioconductor contributed packages repository and from http://www.ivia.es/centrogenomica/bioinformatics.htm Contact:[email protected]; [email protected]

Chemistry, Catalysts, and Processes for Isoparaffin–Olefin Alkylation: Actual Situation and Future Trends

Abstract: As a consequence of the Clean Air Act (CAA), beginning in 1990, USA refiners were forced to change their strategy in order to meet the new mandatory specifications on gasoline composition. The targets established by the CAA were directed to overcoming environmental problems by reducing the ground-level ozone-forming and carbon monoxide emissions from vehicles, as well as toxic hydrocarbons and SO, and NO, emissions in auto exhausts. In order to accomplish this, gasolines had to move in the following direction: Reduce volatility: that is, lower Reid vapor pressure (RVP), especially during summer months, in order to reduce ozone levels. This can be achieved by removing butanes and even C, from the gasoline. Limitations in the aromatic content, with special emphasis on benzene. This can be solved by reducing reformate severity and/or by reducing the upper cut of the fluid catalytically cracked (FCC) gas-oline. Increased amount ofoxygenates, in which MTBE and TAME are preferred, especially in the car...

IJER editorial: The future of the internal combustion engine:

Abstract: Internal combustion (IC) engines operating on fossil fuel oil provide about 25% of the world’s power (about 3000 out of 13,000 million tons oil equivalent per year—see Figure 1), and in doing so, they produce about 10% of the world’s greenhouse gas (GHG) emissions (Figure 2). Reducing fuel consumption and emissions has been the goal of engine researchers and manufacturers for years, as can be seen in the two decades of ground-breaking peer-reviewed articles published in this International Journal of Engine Research (IJER). Indeed, major advances have been made, making today’s IC engine a technological marvel. However, recently, the reputation of IC engines has been dealt a severe blow by emission scandals that threaten the ability of this technology to make significant and further contributions to the reduction of transportation sector emissions. In response, there have been proposals to replace vehicle IC engines with electric-drives with the intended goals of further reducing fuel consumption and emissions, and to decrease vehicle GHG emissions. Indeed, some potential students and researchers are being dissuaded from seeking careers in IC engine research due to disparaging statements made in the popular press and elsewhere that disproportionately blame IC engines for increasing atmospheric GHGs. Without a continuous influx of enthusiastic, welltrained engineers into the profession, the potential further benefits that improved IC engines can still provide will not be realized. As responsible automotive engineers and as stewards of the environment for future generations, it is up to our community to make an honest assessment of the progress made in the development of IC engines over the past century, with their almost universal adoption to meet the world’s mobility and power generation needs. Considering that the maturity of IC engine technology is something that many other technologies/possibilities do not have, we also need to assess the potential for future progress, as well as to assess the benefits offered by competitor technologies, in order to make responsible recommendations for future directions. Factors impacting that future are discussed in this editorial and include the following: