Elucidating the stability of bolaamphiphilic polypeptide nanosheets using atomistic molecular dynamics

Atomistic molecular dynamics was employed to characterize the stability of nanosheets formed by bolaamphiphilic polypeptides. Two different nanosheets (based on RFL4FR and EFL4FE peptide sequences) were simulated to quantify the impact of the bolaamphiphilic nature of the peptides on the structure and energetics of the formed nanostructures. Our results corroborate the structural results obtained experimentally, indicating consistent values for the separation between the peptide planes as well as for nanosheet thickness. Energy analysis indicates that in general the stability of the nanosheets is dominated by electrostatic interactions and nanosheet-water environment interactions contribute considerably to stability. In general, the nanosheets were found to be very stable especially the EFL4FE system that presents a greater energy of interaction between the components of the system. PMF calculations indicate that the free energy required to remove a peptide from the nanosheet is greater than 250 kJ mol(-1) reaching the highest value of 310 kJ mol(-1) for the extraction of the peptide in the EFL4FE nanosheet.CAPESCNPqFAPESPFAPEGUniv Fed Sao Paulo, Inst Ciencia & Tecnol, BR-12231280 Sao Jose Dos Campos, SP, BrazilUniv Fed Goias, CEPAE, Dept Fis, CP 131, BR-74001970 Goiania, Go, BrazilUniv Fed Sao Paulo, Inst Ciencia & Tecnol, BR-12231280 Sao Jose Dos Campos, SP, BrazilWeb of Scienc

A parametric study of a tower controlled by a pendulum tuned mass damper: beam modelling

This paper models a tower with a passive Pendulum Tuned Mass Damper (PTMD) with Finite Elements (FE) using the resources and capabilities of commercial software ANSYS. Although structural control of high and slender towers using PTMDs are widely studied in literature, it was not found yet studies modelling the PTMD with ANSYS. This FE model is called by a routine coded in MATLAB to find the relation between the mass, length, stiffness, and damping coefficient of the pendulum in function of the high vibration amplitudes at the top of the tower (defined as a beam element type). This parametric study of the dynamic behaviour of the PTMD + FE beam structural model is analysed and its results are compared to a genetic optimization developed in other researches to find the best pendulum parameters

A parametric study of a tower controlled by a pendulum tuned mass damper: beam modelling

This paper models a tower with a passive Pendulum Tuned Mass Damper (PTMD) with Finite Elements (FE) using the resources and capabilities of commercial software ANSYS. Although structural control of high and slender towers using PTMDs are widely studied in literature, it was not found yet studies modelling the PTMD with ANSYS. This FE model is called by a routine coded in MATLAB to find the relation between the mass, length, stiffness, and damping coefficient of the pendulum in function of the high vibration amplitudes at the top of the tower (defined as a beam element type). This parametric study of the dynamic behaviour of the PTMD + FE beam structural model is analysed and its results are compared to a genetic optimization developed in other researches to find the best pendulum parameters