Gaston Contreras Jimenez

National Autonomous University of Mexico | UNAM · Institute of Ecology

During fern spore germination, lipid hydrolysis primarily provides the energy to activate their metabolism. In this research, fatty acids (linoleic, oleic, palmitic and stearic) were quantified in the spores exposed or not to priming (hydration-dehydration treatments). Five fern species were investigated, two from xerophilous shrubland and three fr...

A stable and magnetic graphene oxide (GO) foam-polyethyleneimine-iron nanoparticle (GO-PEI-FeNPs) composite has been fabricated for removal of endocrine disruptors-bisphenol A, progesterone and norethisterone-from aqueous solution. The foam with porous and hierarchical structures was synthesized by reduction of graphene oxide layers coupled with co...

A high specificity aptamer-ligand biorecognition and binding system to monitor of dexamethasone (DXN) was developed. The detection principle was based on a label-free electrochemical aptasensor. The selection of the aptamer was successfully performed by the systematic evolution of ligands through exponential enrichment technique (SELEX). From a ran...

Filamentous actin (F-actin) is a key factor in exocytosis in many cell types. In mammalian sperm, acrosomal exocytosis (denoted the acrosome reaction or AR), a special type of controlled secretion, is regulated by multiple signaling pathways and the actin cytoskeleton. However, the dynamic changes of the actin cytoskeleton in live sperm are largely...

Recent advances in large area graphene growth have led to many applications in different areas. In the present study, chemical vapor deposited (CVD) monolayer graphene supported on glass substrate was examined as electrode material for electrochemical biosensing applications. We report a facile strategy for covalent functionalization of CVD monolay...

Endocrine disrupters (EDs) are compounds that specifically interfere with the normal functions of the body’s endocrine system (system of glands for hormonal secretion) by causing adverse effects in both human and wildlife. Therefore, routine, sensitive, reliable and cost effective detection methods for EDs are highly demanded. In this work we prese...

Rising progesterone (P4) levels in humans due to its overconsumption through hormonal therapy, food products or drinking water can lead to many negative health effects. Thus, the simple and accurate assessment of P4 in both environmental and clinical samples is highly important to protect the public health. In this work, we present the selection, i...

One of the major objectives of the Megacities Initiative: Local And Global Research Observations (MILAGRO-2006) campaign was to investigate the long-range transport of polluted Mexico City Metropolitan Area (MCMA) outflow and determine its downwind impacts on air quality and climate. Six research aircraft, including the National Center for Atmosphe...

In Titan's atmosphere there is a permanent transformation of its major constituents, nitrogen (N2) and methane (CH4), into more complex organic compounds. We have conducted a series of experiments in which a simulated Titan's atmosphere enriched with trace gases (C2H2, C6H6, CO) was subjected to short-period cold-plasma irradiations at liquid nitro...

One of the major objectives of the Megacities Initiative: Local And Global Research Observations (MILAGRO-2006) campaign was to investigate the long-range transport of polluted Mexico City Metropolitan Area (MCMA) outflow and determine its downwind impacts on air quality and climate. Six research aircraft, including the National Center for Atmosphe...

The phenomenal growth of megacities, particularly in the developing world, has fueled interest in their effects on climate and air quality on the local, regional, and global scales. During the MILAGRO 2006 campaign, aircraft, satellites, and ground stations were coordinated to make the most intensive measurements to date of the transport and transf...