[en] The cryopreservation of semen in fish, as in many species even shows effects that decrease sperm quality and directly engage cell ability to successfully participate in the processes of fertilization and embryonic development. the characteristics such as mobility and fertilizing capacity of fertilization of sperm are considered to be quality criteria that allow to measure the success or failure of the process, since they are considered integrative variables, being indicators that depend not on a single factor, but on the stability and welfare of all structures, enzymes and subcellular functional compounds that give place to these spermatic characteristics. membrane damage (Adenylate cyclase, ion channels, grouping of other proteins, among others) and their implication in the route of signaling pathway leading to spermatic activation, ATP degradation and fragmentation of nuclear and mitochondrial DNA (genome), degradation of kinase enzymes and other cytosolic proteins (proteome) are considered today, as some of the molecular factors that most affect during cryopreservation and markedly decreasing the fertilizing capacity and mobility of sperm in fish. Proposals on the molecular mechanisms, by which these subcellular factors interact and act as consequence of cryopreservation, are some of the topics covered in this review. Understanding the principles and factors that are involved in the origin of such damages, will allow to improved cryopreservation processes, making them less harmful and more efficient.

[en] The condition of finite and not renewable resource of fossil fuels, added to high atmospheric contamination in big populated centers, for the automotive park that participates in high proportion in the total consumption of primary energy have been unchaining factors for the promotion and study in the country of new energy or bio fuels, starting from organic resources (vegetables or animals). Colombia is a vulnerable country in hydrocarbons in front of exploration programs limitations due to absence of new important discoveries and to decrease of its reserves. Consequently, the country is ad portas of losing its oil self-sufficiency in the short term (2015 horizon) surround by an unfavorable conjuncture of high prices. Everything added to bad quality by the high content of sulphur, particularly in diesel, which overcomes widely the established international levels. To diversify energy sources, to avoid degraded climatic change and to draw social rejection to polluting energy, become important challenges so that science and technology contribute to a sustainable development, well-known and supported by the citizens.