In the present work, we develop molecular dynamics (MD) simulations in the NPT (isobaric–isothermic) ensemble to analyse the effect of an external electrostatic field over a cubic methane hydrate crystallite. The amplitude of the field is in the range 0.5–3.0 V/nm. For the simulations, we used the SPC/E rigid water model and a single-site model for methane at a temperature of 248 K and a pressure of 20 bar. When the external electrostatic field is applied, the water dipoles are oriented in such a way that the methane molecules can diffuse far away from the water cages, hence the clathrate dissociation takes place. This last phenomenon was observed for intensities above 1.5 V/nm. Taking the final configuration of each run as input, we develop a new set of MD simulations, and we observe that the stable clathrate is not recovered immediately when the external electrostatic field is turned off due to limitations in the simulation time.
Metabolic transformations have been reported as involved in neoplasms survival. This suggests a role of metabolic pathways as potential cancer pharmacological targets. Modulating tumor's energy production pathways may become a substantial research area for cancer treatment. The significant role of metabolic deregulation as inducing transcriptional instabilities and consequently whole-system failure, is thus of foremost importance. By using a data integration approach that combines experimental evidence for high-throughput genome wide gene expression, a non-equilibrium thermodynamics analysis, nonlinear correlation networks as well as database mining, we were able to outline the role that transcription factors MEF2C and MNDA may have as main master regulators in primary breast cancer phenomenology, as well as the possible interrelationship between malignancy and metabolic dysfunction. The present findings are supported by the analysis of 1191 whole genome gene expression experiments, as well as probabilistic inference of gene regulatory networks, and non-equilibrium thermodynamics of such data. Other evidence sources include pathway enrichment and gene set enrichment analyses, as well as motif comparison with a comprehensive gene regulatory network (of homologue genes) in Arabidopsis thaliana. Our key finding is that the non-equilibrium free energies provide a realistic description of transcription factor activation that when supplemented with gene regulatory networks made us able to find deregulated pathways. These analyses also suggest a novel potential role of transcription factor energetics at the onset of primary tumor development. Results are important in the molecular systems biology of cancer field, since deregulation and coupling mechanisms between metabolic activity and transcriptional regulation can be better understood by taking into account the way that master regulators respond to physicochemical constraints imposed by different phenotypic conditions.
1 July 2021 in Journal of the Mechanical Behavior of Biomedical Materials
This study shows the benefits of using the environmental product declarations (EPDs), based on ISO 14025:2013, for the configuration and conceptualization of new building materials. Using a quantitative evaluation on these phases of design, it allows one to create materials with lower impacts, in comparison with the existing ones. In this paper, it is proposed to evaluate the potentiality of this tool in the development of a panel from pineapple by-products from agroindustry, used as a thermal insulator. The issue of environmental sustainability was pursued, employing the assessment of the environmental impacts according to characterization methods defined by the International EPD® System. By comparing the possible compositions of the materials under development, with certified environmental declarations of commercial materials, it is possible to identify and select optimal compositions decreasing up to 98.28% of impacts in acidification potential or up to 99.38% for photochemical oxidation—with respect to traditional materials—already at the design stage, where the changes on the composition or the facilities decision have fewer complications.
1 May 2002 in Physica A: Statistical Mechanics and its Applications